Bryan Oakley: Well, I think all the speakers are here so well, people are still trickling in i'll just say this is supposed to be the introductory remarks part i'll just say, welcome to everybody.
Bryan Oakley: Normally we kind of right out of thing and try to make this a more meaningful introduction, but I think we got a lot of technical stuff to deal with instead.
Bryan Oakley: i'll just say thanks for being here like Mike said, this is, after the time change at eight o'clock on a Sunday morning not everybody's favorite time.
Bryan Oakley: And this was on ground, I suspect, few of us would have headaches from the night before but we're all here and and and smiling and ready to to do a presentation.
Bryan Oakley: You know it's been kind of a tradition for mark and I to do in northeast GSA session, and this was supposed to be two combined with.
Bryan Oakley: For convenience who were proposing a session at first ne se GSA and then got canceled and so it's been combined into one and it's really exciting because mark and I are slowly becoming the old guard.
Bryan Oakley: Of this, as we get a few more Gray Harrison and get a little older and our for coke and Venus justin Ari emr and rows are kinda like the for up and coming or four of the really key up and coming coastal scientists out there, so.
Bryan Oakley: it's very exciting to see them in this presentation they're great follows on Twitter, so if you're on social media find them as well.
Bryan Oakley: And i'm happy to be sharing the session with those guys I don't know where mark is I texted him but either he missed the time changer he just forgot that this was today.
Bryan Oakley: How we're going to work, the session today is I don't have an on screen timer that I can click up easily through this platform, so what they've suggested is everybody when you're about to start, presenting just hit go.
Bryan Oakley: On a on a timer or on a stopwatch on your on your cell phone, I will be doing the same thing.
Bryan Oakley: And it's designed to be 20 minutes total counting changeover and sharing screens and all that kind of stuff so what I would say is set your timer for 16 minutes.
Bryan Oakley: If you go a tiny bit over that's fine but it's 17 minutes, I am going to unmute and basically be the voice from above saying hey you know.
Bryan Oakley: You got to wrap it up in 30 seconds or so and that leaves time for a question and change over if you have a question I suggest, putting it into the chat and I will repeat it back to everybody and then we'll answer it that way.
Bryan Oakley: If you can't figure out the chat unmute and ask it, but I think chat keeps that a lot more organized and.
Bryan Oakley: there's also the little reaction button, if you like, things, depending on the version of zoom you have you can click on reactions, I know as a speaker and teaching during this online world the little reactions like that actually do help.
Bryan Oakley: And then, after that that's going to take us through six talks until 1005.
Bryan Oakley: At 1020 we come back for a poster session so everybody can grab another couple of non hotel coffee and each poster is going to be a five minute at most intro video and then there's five minutes of question and answer period.
Bryan Oakley: So that that's how it's going to work for speakers, again we practice this already but you're going to share your screen over and we've kind of got a.
Bryan Oakley: somewhat of a tour of coastal barriers for the first part of the talk and then a couple of more technical aspects related to barriers in the second half of the session or second part of the oral session.
Bryan Oakley: So we're going to start with our first presentation, which is Catherine Hughes and her co author is Mike fenster and she's going to be talking about a overview of berry development, with an emphasis on the US northeastern coasts so Catherine go ahead and take it away.
Catherine Hughes: Great Thank you so much, let me see if I can share my screen.
Catherine Hughes: Alright, so I hope everyone can see this good morning, and thank you so much for waking up on a Sunday for this presentation.
Catherine Hughes: My name is Catherine Hughes i'm a student at ran off making college and over the past two years, I have worked with Mike fenster to examine the development status of the world's mixed energy and wave dominated coastal plain and don't take barrier islands.
Catherine Hughes: I wanted to give the agenda this presentation first and I will walk you through the introduction, giving you the rationale why I decided to pursue this study and my objectives going in.
Catherine Hughes: Then I will go into the methods and how I described and measure each barrier island.
Catherine Hughes: chat hold on making sure okay um I was i'm sorry I was making sure that my everything was going smoothly technology wise.
Catherine Hughes: Then i'll go into the results, starting with a broader scale, the global results, then more specific to the North America east coast and the Northeast GSA region and I will finish with conclusions and the a lot of time for questions.
Catherine Hughes: So being from Virginia, we were very proud that we have 11 out of our 12 mix energy barrier islands that are remaining that it remained undeveloped.
Catherine Hughes: I wanted to answer the question is the Virginia Eastern shore actually the longest natural expansive mix energy barriers.
Catherine Hughes: But when I started to do this, I realized that there's a lack of knowledge on berry development, not only in Virginia, but on mix energy barriers around the world in terms of density of development and types of structures that are dominating the shorelines.
Catherine Hughes: So the original study was just on mixed energy barriers, but after are submitted to the journal of coastal research they requested that we expand our data set to include we have dominated barriers as well.
Catherine Hughes: So primarily my goal was to quantify density and type of development of the world's barrier islands, just to add data to this non existing data set.
Catherine Hughes: That was also curious to see does the hydro, dynamic and or geologic setting influence density and type of development.
Catherine Hughes: In other words, does coastal plain versus delta geologic setting have more or less development and vice versa, with wave dominated and mixed energy and, finally, I wanted to compare the Northeast use a region to in the context of global trends.
Catherine Hughes: desktop analysis utilizing remote sensing provide some unique challenges, there is no boolean data available for the entire world and it's very difficult to identify barriers solely by morphology.
Catherine Hughes: For example, one of the issues that I face, one of the shortcomings of this type of analysis is that it's challenging to discern barrier islands from non very marshlands.
Catherine Hughes: or relic coastal regions, surrounded by del take wetlands One example is shown to the right where there's cloud coverage, as well as more structured marsland.
Catherine Hughes: Also, sometimes the images in Google earth were either pixelated or there was complete cloud coverage over the barrier, despite these obstacles, I use morphology as a proxy for process, because there is no global data available that are both spatially into poorly consistent.
Catherine Hughes: As a result, I looked through every piece of literature that I could get my hands on to cross check every island, I began with Hayes 1979 and I continued our like I continued the literature search with stats in pokey from 2002 and 2011 amongst many, many other sources.
Catherine Hughes: I selected the usgs Anderson classification scheme for a few reasons it is a gland cover system rather than a lead, you system and it's designed specifically to analyze remotely sense data.
Catherine Hughes: I also consider the LCD classification scheme, but this system is only a modification of Anderson Level two showing the figure to the right.
Catherine Hughes: And it's a land use system, and this would require knowledge of human operations and activities, with the intention to obtain products or benefits now this sort of in depth information is not available on a global scale, and it also wasn't available solely for aerial imagery.
Catherine Hughes: The categories of Anderson classification scheme had three levels Level one We selected classification one or urban or built up land.
Catherine Hughes: And then Level two We selected all of the categories so categories 11 through 17.
Catherine Hughes: And then Level three which split each category from Level two into high and low density high density, meaning that there is more than one structure per acre and then for residential categories single family versus multifamily units were the two sections of the Level two residential.
Catherine Hughes: There were a total of 1007 islands measured.
Catherine Hughes: 514 were mixed energy and 493 where we have dominated in terms of geologic setting 450 or coastal plain and 557 or don't take.
Catherine Hughes: All adding up to a total length of 7,690.5 kilometers total.
Catherine Hughes: As I previously mentioned, I use Google earth imagery and I selected imagery from 2015 to 2017 I had to select this this range of data, because there's a lack of imagery in less developed countries.
Catherine Hughes: This is an image of briganti New Jersey and, as you can see there's quality imagery here, but in countries of Africa or Vietnam, there was a lack of imagery especially modern imagery in those areas.
Catherine Hughes: So this is an example of how I measured each barrier I use the Google earth ruler to measure the perimeter, which is the red line, and then I measured 300 meters in the from the shoreline and towards the land.
Catherine Hughes: This is because the shoreline was this this distance was selected because it exceeds most these own inundation areas, so this value serve as a proxy for coastal infrastructure vulnerability.
Catherine Hughes: This is a more zoomed in images stolberg and teen New Jersey, but I wanted to show the two diff some of the different classification types to scale, so you could see that this.
Catherine Hughes: area and pink the single family unit high density is is obviously the neighborhood you can see the characteristics of each house.
Catherine Hughes: And it ends at this blue line which is commercial and services, there is a shopping Center adjacent to the neighborhood they began to the parking lot and continues off the screen.
Catherine Hughes: This figure, this figure demonstrates the distribution of barrier islands in their degree of present development, so the red.
Catherine Hughes: Is the highest percent of development, ranging from zero to 250 50 being the highest possible percent development and zero being zero percent development in that area.
Catherine Hughes: 33% of all barriers were actually defined as coastal plain we have dominated this was the dominant barrier type 20% 20.7% of all barriers are developed.
Catherine Hughes: And 18.8% of all barriers are complete undeveloped which means they're the areas in the green, they are the areas that have no development on the shorelines.
Catherine Hughes: single family unit high density was the dominant development type and residential land use, actually, the combination of multifamily units and single family units dominated shorelines.
Catherine Hughes: This graph shows the total length of barrier islands by country, compared to the total percent development for these countries, so the top three most developed countries are the United States followed by Italy and Vietnam.
Catherine Hughes: The United States also has a significant margin of length over other countries and Italy and Vietnam is important to note that they have disproportionately smaller shoreline length compared to their percent development.
Catherine Hughes: The US actually has at least twice as much shoreline as any other country in the world, or by an order of magnitude.
Catherine Hughes: So I wanted to zoom in next to the North America east coast to compare the southeast and the Northeast regions.
Catherine Hughes: The North America east coast contains 25.9% of all global barrier shoreline length and 54% of all global development, so all over half of the world's development and barrier islands exist in the in the North America east coast.
Catherine Hughes: makes energy shorelines predominate with 31 wave dominated barriers and 120 mix energy this adds up to 951 kilometers of wave dominated shoreline and 1,437.5 kilometers of mixed energy total length.
Catherine Hughes: This is important because, even though individual wave dominated barriers are common longer than individual mix energy barriers makes energy shorelines cover a greater linear distance.
Catherine Hughes: also notice that there is a trend of higher development in the south, that decreases development going North with the acceptance of New Jersey.
Catherine Hughes: This is another graph of total length versus percent development but it's specific to North America, each region in the light blue is in the north eastern section in each region in the dark each section, the dark blue is from the south east region.
Catherine Hughes: The southeast overall was more developed in the north, east and Florida is the longest barrier chain by good margin and it's also the most developed with 72.7% of Florida shorelines being developed.
Catherine Hughes: New Jersey, is the North East, North East longest barrier island shade but it's also a second in the percent development at 66.5% and similar to global trends, the length of North East barriers are disproportionate to their personal development.
Catherine Hughes: Now specific to this conference here the results 9.9% of global development is located in the GSA northeast region and 5.5% of total barrier lengths worldwide.
Catherine Hughes: And this image there, the only orange in this region is balanced in New Jersey and the only area that has zero percent development is balanced in Canada.
Catherine Hughes: Now we also wanted to know the types of development in the northeast region and the following slide shows these results.
Catherine Hughes: Okay, this graph shows the breakdown, a development type in kilometer of land use per State or region from north to south from left to right each color corresponds to a classification type.
Catherine Hughes: Now New Jersey, is the most developed as the Northeast region, as I mentioned, but it's also unique about New Jersey, is that 4.28 kilometers of.
Catherine Hughes: The shoreline is dominated by commercial and services and that's the highest value on the entire North American east coast and that's one of the highest values in the world.
Catherine Hughes: So when I was zooming into Google earth to look at these structures there's a high density of restaurants shopping centers or other entertainment public service facilities directly on the beach summer sitting just right on the shoreline.
Catherine Hughes: Next New York has the highest density of transport transportation communication and utilities in the entire world and that's it has 10% 10.9% of its land use dedicated to this area.
Catherine Hughes: Again on a zoomed in on Google earth New York had the highest amount of either parking lots or roadside assistance structures associated with transportation directly on the beach.
Catherine Hughes: To summarize the results coastal plain barriers engine in the world are more developed than they'll take barriers with corresponding values of 25.6% development for coastal plain and 11.9% development of delta barriers having development.
Catherine Hughes: Mixed energy barriers are more developed than wave dominated barriers again with the corresponding values of 20.6% development for mixed energy barriers, and we have dominated barriers having 15.4% development.
Catherine Hughes: United States contains the most development worldwide, and more specifically the east coast barriers of the United States Nega over half or 53% of global development.
Catherine Hughes: Finally, residential land use combination of multiplayer and single family unit homes was the dominant type and although the the North East region has smaller chain length, it has unique values and that it has diverse land use applications.
Catherine Hughes: Are there any questions Thank you all so much for listening.
Bryan Oakley: Thank you, Catherine that was very interesting and I look forward to seeing that paper because I think these kind of inventories at this scale are really useful resources for those of us studying barrier systems.
Bryan Oakley: Because we have plenty of time for questions so if anybody has any go ahead and read them into the chat and we'll make sure we get them conveyed.
Bryan Oakley: i'll ask a one that it's kind of a standard question, what do you think when you set out to do this, what do you think is the most.
Bryan Oakley: Interesting or unexpected thing you you figured out doing this kind of analysis.
Catherine Hughes: Well, I was sort of I was sort of shocked honestly by.
Catherine Hughes: The amount of barriers on the east coast, the United States, compared to everywhere else, I mean there's not it's there's barely even in comparison to other countries in the world, so that was really interesting for me to know because I grew up.
Catherine Hughes: You know, always admiring the Virginia barriers and I knew there was a lot of them here, but I didn't know how exactly how many there were you know in Florida or all around the coast of Florida is crazy.
Bryan Oakley: Any other questions for for Catherine.
Bryan Oakley: Come on, everybody wake up it's still early I know.
Bryan Oakley: I mean, I think some of that is not unexpected, I think, putting it in perspective between Florida and New Jersey.
Bryan Oakley: is really important, because obviously Those are two of the hot spots, as we head into the next few decades of coastal management and coastal hazards.
Bryan Oakley: So I think that's it's interesting I almost would have thought New Jersey beat Florida so that's in terms of development so that was.
Bryan Oakley: That was an interesting slide for me, and particularly in the New York transportation utilities aspect as well that points out a really important vulnerability for that state.
Catherine Hughes: That has a large percentage of impermeable surface that's right next to the beach.
Bryan Oakley: Any other questions for Catherine.
Bryan Oakley: Can you can just ask on zoom if you want Chris yeah that's fine.
Bryan Oakley: And then Mike i'll give Chris a chance and then i'll ask your question, yes.
Christopher Hein?he/him: Great job Catherine Hello yeah.
Christopher Hein?he/him: hi nice to see here um.
Christopher Hein?he/him: I was thinking about the the inside the barrier islands inside estuaries you know I now have this new bias, no longer in the northeast section.
Christopher Hein?he/him: By Chesapeake bay and all of these fetch limited Barry around are those included in your analysis as well now thinking about some major asteroids, particularly on the east coast.
Catherine Hughes: So that was actually one of the face that goes that one of the obstacles that I did face was trying to distinguish those inland barriers from the directly ocean facing barriers.
Catherine Hughes: We only measured the ocean facing barriers so we made we measured, the ones that were had no connection to the shoreline whatsoever.
Catherine Hughes: Especially from the limited amount that you can see, like if you zoom in on Vietnam it's very difficult to see the connection to the mainland on Google Earth.
Catherine Hughes: So it became too tedious and too tricky and I didn't want to count sections like I showed in the the first or second picture.
Catherine Hughes: Those marsh like they look like barriers but in many areas of the world, we just couldn't have the quality of data to establish those barriers and also one of the things that we define a barrier, as is having an accumulation of sediment in the front.
Bryan Oakley: Thanks, so we have about a minute and a half a question, so let me just Mike asked a quick one.
Bryan Oakley: about the Community think my i'm going to hold that question i'm sure we're going to have some breaks where we'll have some time to talk about that what I like that idea, though, let smoking, maybe open that up to everybody and and a little bit.
Bryan Oakley: megan COP asks what do you think this means for sea level rise vulnerability and flooding.
Catherine Hughes: Oh, it has huge implications, especially in Florida and New Jersey to, as you mentioned, I thought that this study would be useful, just to understand that.
Catherine Hughes: 300 meters is not that far from the ocean if you're really looking in so that does not give much room for growth earth sea level expand to the sea level rise, so I really see that being an issue.
Catherine Hughes: Any big storm wipes through that's going to really affect the infrastructure there, and also the stability of that shoreline.
Bryan Oakley: and Catherine, if you can do this, one in about 30 seconds great if not we can point it to later, but our he wants to have basically, how can you remind him how you did the land use classification and if hotels were classified as commercial.
Catherine Hughes: hotels were not classified as commercial in the Anderson scheme multifamily units, whether they are for profit or not for profit were considered as like apartment complexes were considered as multifamily units underneath of residential that's a great question.
Bryan Oakley: Thanks, and we will have some time, will you know either people can hang during the break or during some of the posters I bet we'll have some time to do some general discussion, thank you, thank you.
Bryan Oakley: That was a very good talk Catherine alright.
Bryan Oakley: So we got about 10 seconds until we get on to our time for our next one, so, while we do that if Alice if you want to go ahead and share your screen and then we'll get started in a SEC.
Bryan Oakley: Alright, so our next talk is Alice sorrow and her co authors are Duncan Fitzgerald and so Hughes and she's going to be talking about the castle neck barrier.
Bryan Oakley: Which is on the Massachusetts shoreline so Alice go ahead and take it away.
Alice Staro: Thank you, I am ready to start and mentioned and went to talk about the pattern of erosion and the position along Castle neck by that island and in Essex be.
Alice Staro: Both on on the cadence scale and also specific storm related we care about storms, because we know that one of the consequences of climate change in New England is going to have.
Alice Staro: Increased storminess and increase northeastern events so if we put example, if we look at the video down here, we see how still date in Massachusetts got affected by the 2018 storms.
Alice Staro: The northeastern states that happened here from around November to April, so we focused on customer, that is, as we know, located in the Gulf of maine the southern part of it in.
Alice Staro: Massachusetts and it's actually our parent level barrier island pin to the bedrock where the title in let's are in the lowest of the infrastructure lows.
Alice Staro: And it's contrast between plum island and coffins beach in the merrimack environment it's a major title environment with a time range from 2.7 meters with similar sites it's mixed The wave wave dominated added value and it's dominated by nor'easters soft storms.
Alice Staro: It looks like that so it's.
Alice Staro: It says it's a couple the system with a title inlet and the barrier island.
Alice Staro: Behind the barrier, there is an extensive extensive marsh part of the grid soul marsh and there are several different type of send reservoir so we have the beach itself here the deals then read.
Alice Staro: The show soft sure of custom neck the shows with the implemented on sound and with the India 630 million lead.
Alice Staro: So it's a highly dynamic environment and, if you look at this movie from.
Alice Staro: Google earth time lapse, we see that changes are happening constantly so each frame here represent the year and we see that the major variation are happening here.
Alice Staro: Where there is these hooks to grounds for me and down here at the speed in this area, we also see that show some constantly switching migrating forming getting removed also here around here of the at delta off shore Castle neck and implement on some.
Alice Staro: So we really wanted to try to assess and predict the formation and remove all of this and deposits and the shows both along the beach and within the Essex three left.
Alice Staro: So we approach the problem with four different methodologies, we will send them into logical analysis to characterize sediment reservoir a story from shorelines to decide to inform the direction of sediment transport you we use remote sensing to.
Alice Staro: inform about the effect of specific and single storm and then we will apply modeling to predict the future stones.
Alice Staro: So on the term of grain size, we collected more than 300 samples, we see them once with a mechanical sitting from zero to 3.5 feet and.
Alice Staro: We use math to calculate the statistics following up for can work so basically it's mainly medium find send and we have that defined samples at found here down in that in the River Delta.
Alice Staro: million lead and hearing the Oscars while the largest Gray sides are found here between these drumline to brands and along the beach, and this well in these shows down at the speed.
Alice Staro: The 50 hits kind of the same, we have this type of distribution and then in terms of sorting miss most of the sandy's very well sorted awkward is moderately well sorted.
Alice Staro: And the moderator will sort it can be found here and some somehow around the beach up here and in the world salted is evenly distributed it's not specifically located to a single points.
Alice Staro: So after that we approach the story construction methods to see in terms of decades, how is the sediment transport acting in this area, and so I use trace contour line over the certified photograph and confronted them compare them with.
Alice Staro: Lancet images so it's a 30 meter resolution it's pretty course and.
Alice Staro: I did, that when when there was multiple imagery for specific decades I trace both of them define a place where we had an equation from.
Alice Staro: The historical one to the present or the more recent one.
Alice Staro: Then we were there was a decrease in size and also the find an area where there was the maximum change maximum maximum change within the syndicates it's just a visual comparison and they did that, for the 30th.
Alice Staro: The 60s 70s, the 90s, the 2000 and finally everything compared, we see that there is.
Alice Staro: Agreement with all the videos and what we could expect that this area here, where there is a hook to brands and in this Peter the most affected by changes.
Alice Staro: Here is the place where there is more the creation in size of the speed forming and converting in ensures one here we have.
Alice Staro: The agreement in saying that there is a creation here so sediments it's constantly to work and remove in but it's not transfer the way from the system, probably.
Alice Staro: And also, we see that these aerial photograph from this lens at images show that there is this peak this hook forming and building up here that it's not comprised into these shoreline map contour line.
Alice Staro: After the standard commercial lines, I decided to see how he's going to if it was possible to actually map the effect of a single specific storm, so I approached with remote sensing and satellite imagery.
Alice Staro: Normally, this is approach that it's avoided in coastal and title in that, because of the high density of the of the high dynamic of the area.
Alice Staro: And because normally the resolution of the satellite imagery is not high enough, but these satellites that could not in scope, provide a 3.7 meters solution and it's.
Alice Staro: highly accurate and I collected two different images to compare to see the effect of the northeastern 2018 sequence and.
Alice Staro: I make sure that both of the imagery were acquired during low tide, with no ice no clouds vegetation, that was not growing but also not completely dead.
Alice Staro: And acquired possibly around the same time of the year, and so, these are the two imagery that we that they got one is from 2017 and the other from 2000 in teams so before the onset of the sequence, in a few months after that.
Alice Staro: few months because we went to avoiding the vegetation growth on the island, there was acquired during the lowest possible tithe available so here in here.
Alice Staro: And then I use the change detection analysis that again is typical of remote sensing to map and identify changes in different land corporate classes and it's an algorithm based on set of decision, yes or no it's a decision tree so machine learning type of analysis.
Alice Staro: There is, it is a classified map when which we have seven classes three of stable.
Alice Staro: type of land cover so stable water stable sentence table vegetation as as we could imagine the ocean, the inner part of the barrier island, for example here and here it's coffin coffin speech and then.
Alice Staro: Some parts of the beach itself, and then I have defined for classes of chain, so we have send converted to vegetation and water and send converted to an vegetation or sand converted vegetation of water converted to Sam.
Alice Staro: We see that the again the most dynamic areas are here down the speed, where we have a lot of.
Alice Staro: classes and peaks of spectral response changes and also here and as well in the plum island some same also we see changes happening here in the anybody in that.
Alice Staro: We can then decide that Okay, how do we read that those terms that it's interesting geologically, we can say that there is a.
Alice Staro: general sense the reservoir loss of 1.6 kilometers squared that can be interpreted as doing and doing the traditional procreation and beach erosion on show migration.
Alice Staro: and vice versa, vice versa 4.7 kilometer square of centers of war game as beach migration landlord show information show migration close to the beach show information and migration in the River mouth and in the channels.
Alice Staro: Okay, so we were found how to read the day environments on a decade scale scale how to determine and decide how much standards movies and reward and where it's moving.
Alice Staro: For specific storms, so now we want to try to predict in the future, how it's going to change so to do that we had decided to do modeling.
Alice Staro: And we are in the process of doing it, so we already collected the reference profile pre and post storms, we did three surveys, with the application and.
Alice Staro: We are creating the grid for X beach integrating the DSM is the CP data and optional but imagery to make sure to cover the to have the correct depth of the channels here and the depth of the picture here.
Alice Staro: So we collected six profiles, taking into account their location compared to specific feature, we were interesting it so, for example, this.
Alice Staro: We saw that it was constantly moving and also down here to take into account, for example, the dune systems that we were assuming that would be changing a lot with different storms.
Alice Staro: We also being considerate in terms of conservation and preservation of the happiness clever piping bloggers and listing sites that breathe and nesting in the view of customer.
Alice Staro: So our profiles look like that and.
Alice Staro: The 5210 don't change it a lot from the June survey to the September and October one so from the pre storm to the post or one.
Alice Staro: But T for MP3 or the most affected one so, for example, in the first one, for we see that the summer burn.
Alice Staro: That smart from the blue in the blue profile that gets slightly elevated in the in the yellow one gets completely removed after the storm in October and slowly, it leaves the beach with.
Alice Staro: A smoother and more uniform slope, the same way in D3 we have the salmon berries removed and it's switched to a full Berman, a higher.
Alice Staro: elevation and it changed a bit to this look of the beach itself with the other profiles, there is a slight elevation change in the in these areas for here here and here.
Alice Staro: So to conclude.
Alice Staro: With we have demonstrated that we have in this environment large volume of standards can trance can be transferred from different reservoirs.
Alice Staro: After specific thresholds are crossed, and they don't normally don't leave the system these systems that we're talking about are the plum island speed then plum island.
Alice Staro: In that channels and that delta claim beach protuberance and the beach itself, and then the speed on thing which.
Alice Staro: We also know that the sand gets transferred southward in 1520 years but during this time, the beaches, not in a steady state it gets on their.
Alice Staro: erosion and the position constantly, so there are some main features that can be pinned like we have the speed growing.
Alice Staro: Or the northern protuberance growing and the speed to reducing its size, but at the same time, the beach goes under different processes.
Alice Staro: And also, we have found out that we can this we can approach the single storm effect using remote sensing so its innovative because, as I was saying was not an approach us before.
Alice Staro: Also, because the Lancet, for example, is a 30 meter resolution and so makes it impossible to clearly see the shorts in this type of environment.
Alice Staro: So, in the future, now we want to finish and apply X beach and to try to predict the effect, and the response of a single storms.
Alice Staro: with different thresholds different values and the fact that they will have on Castle neck and to see how it will change the mythology of Castle neck and possibly in the area of Essex admitting that.
Bryan Oakley: Like Thank you Alice Alice that was very interesting, we have plenty of time for questions so.
Bryan Oakley: Anybody with a question, you can either unmute and ask or type it into the chat.
Bryan Oakley: i'll ask what else I missed it i'm sorry I was getting set up for the next talk and the the design algorithm work, you were doing what what software, we doing the analysis in.
Alice Staro: Simpler um you asking about.
Alice Staro: The storms one.
Bryan Oakley: This one yes correct.
Bryan Oakley: The change detection.
Alice Staro: Oh, I use um so for for the mapping itself, I used a J yes.
Alice Staro: So it can be done both on today, yes or rgs doesn't matter.
Alice Staro: The process itself it's just selecting.
Alice Staro: Training data set of pixels that can be assigned a specific values, so that the algorithm know exactly this vector responses your urban areas or this factories policies vegetation and also.
Alice Staro: Also to be fair, I added in my image classification.
Alice Staro: spectral indexes sorry too much these ones.
Alice Staro: Okay, so in this way, I could highlight highlight where soil with these index that it's called dissolve in water bodies standing water bodies.
Alice Staro: channels and possible ponds, to take into account the fact that the images were not in again that the same values of side.
Alice Staro: So it could be different, water and then vegetation here, so this is the part that can be done with Jay yes so for the organism it's a decision tree.
Alice Staro: And there are different type of algorithm in machine learning that could be used to this type of analysis, if you use decision tree random forest.
Alice Staro: neural networks, but we use a code that is built that view is there is a wide group of remote sensing people as you.
Alice Staro: guys may know and they've built their algorithm to run decision tree and they think they're going it all is just about to be published or it's been published recently, and they also implemented it.
Alice Staro: To be at some point freely available through Google or search engine at the problem with Google APP engine is that you only you can only use.
Alice Staro: Google available.
imagery so answer.
Bryan Oakley: Thank you, and I could just see you know from post storm kind of being able to run an analysis over a large area and map out overwatch and wash over a fan deposition and.
Bryan Oakley: You know, in a way i'm a field geologists, and all this remote sensing kind of scale satellite stuff is a it's a little bit Greek to me but.
Bryan Oakley: it's very.
Bryan Oakley: it's very cool stuff, though, and you explain that very well, thank you, that was good.
Bryan Oakley: Any other.
Bryan Oakley: Any other questions for Alice we've got about four minutes, so our next talk.
Bryan Oakley: chloe had a question so Alice since he saw more gain of beach material than loss in your change analysis does this imply there's a settlement input to the system, and if so what's the dominant source where's the sand coming from.
Alice Staro: um.
Alice Staro: So I would say that it's not mainly sediment coming to the system it's many sediment reward, but we know that the resettlement that could get delivered from like your phantom island.
Alice Staro: I would also say that this type of analysis needs some improvement because um.
Alice Staro: it's still tricky Okay, yes we're saying it's not the image it will not acquire the same exact tied so some of the things that might get consider underwater here, I would say not if we are exactly in the middle of have a short but if we are on the edge of it it's tricky to see it definitely.
Alice Staro: showed it's definitely submerged and also there is to take into account that the light is unlimited depth of penetration so everything that could be, for example.
Alice Staro: We could have shows down here not likely, but we could have a show that that's not going to be seen by the satellite because it's the water is too too deep.
Alice Staro: We have, we know that the resettlement that gets accumulated within the sex river so down here, because the army corps of engineer plan to dredge the chat everywhere, very often, because it gets full of sand so.
Alice Staro: I think that more than sediment new sediment deliver to the system it's sediment gets constantly the work, and this is a fan divided island so also if you are on the beach somehow you could get extra send in the system.
Bryan Oakley: I can, for that any other questions justin do you have a general sense, on the order of magnitude for the volume of sand kind of transport, did you know what the what the raw numbers would be roughly input output.
Alice Staro: Yes, should be around them millions of meat, meat, meat cubic meters.
yeah.
Bryan Oakley: Thank you, Chris for correcting my pronunciation it's not Alice sorry Alice if i'm.
Bryan Oakley: sure.
Bryan Oakley: i'm americanizing your name I apologize for that.
Bryan Oakley: My my my friend, Chris pointed out to me with the direct message, so I apologize for anybody's name my butcher i'd say my students, you know, I think that.
Bryan Oakley: While we wait for the next talk to queue up the most terrifying thing for me or not I don't get scared lecturing I don't get bothered by it, but the first day learning to pronounce everybody's name is always the hardest day for me, so I appreciate that Chris and I apologize house.
Bryan Oakley: Alright, so i'm going to i'm going to kick you off.
Bryan Oakley: And our next speaker.
Bryan Oakley: megan you can go ahead and share your screen over.
Bryan Oakley: i'm gonna go into presentation mode just to make sure we're all set to go.
Megan Kopp: I mean good.
Bryan Oakley: not quite yet it's there you go so hold on ones okay we're on time perfect so our next speaker is going to actually take us to the fourth coast and.
Bryan Oakley: megan COP and her co author Noah snyder going to be talking about changes on sandy pod spit in Lake Ontario so megan go ahead and take it away.
Megan Kopp: All right, hi everyone, thank you for joining us today, my name is megan and I am a second year masters student at Boston college setting with Noah fighter.
Megan Kopp: And i'm here to share some results from my thesis, this is a study that is sponsored by a GSA graduate student research grant, and this is a drone photograph of my study area.
Megan Kopp: So, first I want to provide some context for the location and motivation behind the study before I claim the analysis.
Megan Kopp: The sandy punks bit is a north, south trending barriers that system on the eastern shore of Lake Ontario the longshore transport is North and there's one in like connecting the back barrier North sandy on to the eastern lake Ontario.
Megan Kopp: The type of forcing of tied in negligent at this location, because of the lake Ontario study area.
Megan Kopp: The prevailing wind direction is from the West, and because of this, it is aligned with the long access of Lake Ontario which will result in.
Megan Kopp: High waves build up that can affect the eastern shore, in particular, and here are some ways roses from the near shore and oswego and the offshore believe in the middle of Lake Ontario.
Megan Kopp: there's one study about this location, it was completed by mateus and his colleagues in 2016 and essentially they recreated a historical analysis of the change of the barrier split system.
Megan Kopp: From the 1870s to 2013 and in this, they were able to locate the prior channel locations and see how the inlet with migrating north, as well as the development of record that along the.
Megan Kopp: Other side of the in life and in this study, they concluded that the lake level was the predominant driver of GEO morphic change to the barrier.
Megan Kopp: So in addition to this, to understanding this lake level, there were two high water events in 2017 and 2019 that drove me to study this area because of the effect of Lake level on the geo morphology of the system so here is a.
Megan Kopp: profile of the mean monthly like elevation from January to December from 2001 to 2020 which is my study period.
Megan Kopp: And as you can see, these two red lines which are the 2017 and 2019 profile are significantly higher than the rest of the study period, indicating that the lake level.
Megan Kopp: has produced a lot of change or could be, the suggestion of a reason for a lot of the change during this period in Gray, is the ordinary mean high watermark which is us as a datum for my study and is 75.4 meters of elevation.
Megan Kopp: Mathias at all, also recognize that the other forcing driving GEO morphic change in addition to water level where the ice cover and the storm frequency and strings.
Megan Kopp: And so I want to acknowledge these because these might be more relevant or important on a shorter temporal scale, this is what the ice build up looks like on the shore of Lake Ontario, and this is an animation.
Megan Kopp: Of the ice cover.
Megan Kopp: The historical ice cover from the 1970s to now, and you can see that the ice predominantly builds up in the eastern shore if it is going to build up this is a picture from a shipwreck that was in the 1880s.
Megan Kopp: That was uncovered by sandy by the erosion and movement of sand this past summer, and this is a picture from the a Halloween storm in 2019 That was a significant erosion vent at during the study period.
Megan Kopp: So this led me to want to investigate what sorts of changes are occurring at a higher done temporal resolution and how they are measurable, as well as what changes attributed or could be suggested from these two high water abundance in 2017 and 2019.
Megan Kopp: And to do this, my main method of looking at this analysis, using digital elevation models and the D are from 2001 to 2020 and.
Megan Kopp: Using the DM I would extract three metrics of change to evaluate the G morphic change in those metrics are the shoreline position and elevation the doing CREST isn't an elevation and the volume of debate with the burial deposition and erosion.
Megan Kopp: And so, for the methods, I have a suite of lidar data available from the noaa coast data access viewer and then some fieldwork and my in my field work, I was able to use.
Megan Kopp: A few as photograph so in our data and our tk GPS data to create my own D, so the light or D young's are from 2001 2007 2011 2015 to 2018.
Megan Kopp: And those resolutions range from one to half a meter pixel resolution, with the exception of 2001, which is a much sparks their point guard.
Megan Kopp: And is a resolution of four meters and then my junk later we used with structure for motion to create a deal of a half meter resolution from the summer of 2020 and then from these I was able to create the difference which were also used for volumetric change analysis.
Megan Kopp: So, to start with my shoreline analysis there's three main intervals of change that i'm looking at in this study, the first is before the high water events from.
Megan Kopp: And then from 2015 to 2018 which brackets 2017.
Megan Kopp: I wanted that and then from 2018 to 2020 to quantify the 2019 high water event and my shoreline analysis results were presented at large at the national dsa so I just want to summarize them really quickly here.
Megan Kopp: This right here is an aerial photograph from 2016 and these insects that I provided here show how the shoreline has fluctuated over time, where the lighter blue contour lines represents earlier.
Megan Kopp: shorelines and the darker lines represent more recent and every one of these contours extracts the ordinary mean high watermark which I use as a data at 75.4 meters so as you can see how the inlets changing as a result of.
Megan Kopp: overtime and it's vibrating North and this analysis over these three intervals that i'm studying found that before the high water events, the mean shoreline change was actually positive, which means that the shoreline was advancing whereas during the high water of an.
Megan Kopp: interval of 2015 to 2018 it retreated about almost two meters, on average, and then in 2019 to 2020.
Megan Kopp: That actually retreated significantly more at about almost six meters indicating that these high wire events did drive morphologic changes as far as the shoreline goes.
Megan Kopp: But today i'd really like to talk about the dune press analysis and the volumetric analysis that i've done so for the dude press analysis which i'll start with.
Megan Kopp: I surveyed with the drone seven different ecology and morphic zones which I used to characterize the different topography along the fit based on the density of vegetation and.
Megan Kopp: The release and that he should be done by selected a representative transact.
Megan Kopp: to study how the doom cast has changed in that zone and these transactions are shown here in this pinkish coral color and that's what i'm going to show you.
Megan Kopp: Today, and these trends like we're extracted directly from the vm so i'm just going to do in on this study this stone right here, this first donut behind it, which is a high elevation dune.
Megan Kopp: And as you can see the light lighter blue again is an earlier period of time and the red represents the 2018 events which are after the high water bunch of 2017 and the orange represents.
Megan Kopp: The August 2020, which is the after the high water event in 2019 and chose my structure promotion so from 2011 to 2013 at this location, but doing cross.
Megan Kopp: validation decreased 2.31 meters and it moved horizontally East about five meters and while changing into this right, this is about 26 centimeters per year of elevation lots.
Megan Kopp: And eastward movement of about half a meter for years, a year so it's pretty significant and definitely has a strong signal.
Megan Kopp: This right here this noise here is a result of vegetation and the structure for motion structure for motion, you cannot ignore or.
Megan Kopp: vegetation cannot be mapped out so this signal here is on as a result of elevation so I draw your attention to this doing face here, which is retreating back horizontally and vertically.
Megan Kopp: To take a little bit of a better look at this trends like specifically, I want to show that how this relates, the water levels.
Megan Kopp: So these bottom lines here are the ordinary mean high watermark and then the 2020 monthly high, whereas these lines here which are close together or the 2019 and 2017 monthly high water events.
Megan Kopp: And you can see that the inflection point on the 2020 profile is right at this doom toe matches up very nicely, but the 2019 and 2017 high water.
Megan Kopp: leak levels, suggesting that this is the result of the high water event is causing the horizontal movement and that's horizontal erosion and there is a significant signal between these blue pre high water events, the red and the orange events after the high water.
Megan Kopp: To give you a better idea of what this looks like on the larger spit here are some additional translate data that i've extracted and again, all of this.
Megan Kopp: The Orange lines that are vertical or noise and the structure for motion but I draw your attention to how the profile changes from the blue pre water events to the red high water events and in every case, it creates a steeper slope.
Megan Kopp: Where they're doing is retreating horizontally back and even if the doing cross isn't changing it's creating a steeper more unstable for June profile.
Megan Kopp: Next I computed the volumetric analysis change and do this I use the terms of difference, so at this I use the roster tool to subtract the older DM from the higher DM or the older DM from the.
Megan Kopp: Probably the more recent DM from the older dvm were in red is erosion and in green is deposition.
Megan Kopp: And this is a sequence of what this looks like using the available lidar coverage from 2007 to 2018.
Megan Kopp: From 2007 to 2015 and from.
Megan Kopp: And as you can see the intervals of calculating volume change in this area is largely going to depend on the lidar coverage, so, in some cases, the pre water interval turned into 2011 to 2015 instead of 2007.
Megan Kopp: But the predominant change is along the beach face here and in this high water event bracketed by 2015 to 2018 you can see, there is a lot of erosion here.
Megan Kopp: And the main changes deposition at the inlet on this side on the South side and on the North side of the inlet works eroding and moving north.
Megan Kopp: So to do this analysis I separated out this the burial and so basically this boundary to compute and differentiate between these two.
Megan Kopp: what's happening in the underneath the water level and above the water level and I decided to use the.
Megan Kopp: Ordinary mean high water mark for that, because.
Megan Kopp: That was the contour that was before the high water events.
Megan Kopp: Okay.
Megan Kopp: So, again looking at that same area that I was studying before here this thing inset is what I was showing earlier with the transact data, and this is a test of this volume change analysis which i'm still working on completing.
Megan Kopp: So this is a do D from.
Megan Kopp: And we're again we're erosion is red and deposition is green, and this is the transact line that I had shown you earlier.
Megan Kopp: The error of the cod is about 36 centimeters with a 95% confidence interval of about 71 centimeters.
Megan Kopp: And what I did here is I calculated the volume change across the entire God and then I applied a 95% confidence interval as well, so isolate the statistically significant change.
Megan Kopp: And, in both cases, the net volume change of this God was not original.
Megan Kopp: Which again supports the fact that the 2016 and 2017 highwater event included in this interval.
Megan Kopp: was likely a part of and drove a lot of this to morphic change to this part of the barriers that the thickness of this material overall ended up being.
Megan Kopp: Of of the part that was being.
Megan Kopp: removed was 26 centimeters across the entire God and almost one and a half meters.
Megan Kopp: Over the statistically significant change at the 95% confidence interval.
Megan Kopp: So this is another way of looking at this data, where this is the God that I just showed earlier where it's the raw God, without any sort of threshold and error and then this is isolating just the 95% confidence interval so anything that's lower than the.
Megan Kopp: This.
Megan Kopp: This within the 95% confidence interval is colored whereas everything that could be considered air.
Megan Kopp: Is grayed out.
Megan Kopp: And the bar graph show what this looks like in terms of the volume, where the red is erosion, the green is deposition and the greatest than that volume change and in both cases.
Megan Kopp: There is significant erosion, as the difference here.
Megan Kopp: indicating that this inner during this interval erosion, with the dominant.
Megan Kopp: not changing volume and the transaction again it's the same transact that I showed earlier, but now I just got the 2015 and the.
Megan Kopp: profiles, to show all of this net volume loss that occurred, so you could think of this gap between them, so this is all the material that was removed during this high water event.
Megan Kopp: So to summarize to summarize all these finding the.
Megan Kopp: shoreline net advance about 3.62 meters, on average, or experience events before during before the high water events and the democrats actually increased across five transactions.
Megan Kopp: That I was showing earlier, but after the 2017 high water event during the 2015 to 2018 interval the shoreline actually retreated the dune CREST decrease.
Megan Kopp: And the volume of change was an erosion indicating tidewater been has been terrific GEO morphic cause significant gillmor to change to the sandy ponds.
Megan Kopp: And then, after the after the 2017 higher wat water events from 2018 to 2019 or 2020 during the high water event of 2019 the Charlene again retreated Adam me even more increased rate.
Megan Kopp: On average, and again we're doing cross decrease suggesting again, so these two high water banks have driven.
Megan Kopp: A lot of the gene morphic change that has occurred to this study area from 2001 to 2020 so in the future, I look forward to isolating more volumetric change to see how.
Megan Kopp: Different parts of the fit have responded to these high water events and better understand what properties are driving these.
Megan Kopp: With that I thank you for listening and I will take any question, this is a another gentleman photograph of that channel.
Bryan Oakley: Great job making that was really good, and I think these high water events are such important indicators of.
Bryan Oakley: How Barry systems respond as water levels come up that we don't get to see on the coastal.
Bryan Oakley: systems as much, so we have a couple questions coming in Mike fenster asks, can you speculate on the cause of the changes in particular the role of storms compared to other drivers, like the high water events.
Megan Kopp: it's really hard to isolate the storm, like the fact of a high wire event versus the frequency of storm, because this is such a complex system in the lake level of Lake Ontario.
Megan Kopp: Actually, but so significantly throughout the year if you might have been able to see by the profiles I showed earlier, but the the frequency of the storm is increasing, so one of the questions I have is at this high temporal resolution that i'm looking at do these storms have a.
Megan Kopp: more significant role in driving to morphic change then maybe the water level does that a decade old time scale and I don't really have a great answer but i'm also curious about that.
Megan Kopp: But I do know that there is that they have increase in frequency and that the water level and storm events are are coupled right, because if you have a higher water level, to start with, then that same storm is going to drive.
Megan Kopp: it's going to cause more King then maybe that a storm of the same strength would lower water level.
Bryan Oakley: Thank you, the other question comes in, from rose and it's she's asking where do you think the sediment goes does it stand the barrier system does it go longshore do you think it's going offshore.
Megan Kopp: yeah that's a great question on the launcher transport is to the north, and this mckay's it all calls the system closed, meaning that there's no sediment source from a river farther south is this allowing sediments move up so.
Megan Kopp: I, my understanding is that it could be in terms of offshore sort of the recycling of these sandy glacial sediments from the retreat of bill or ancient ice sheet, but the sand and.
Megan Kopp: longshore is actually going in and filling that enlighten that Blackberry upon so there's the show that developed.
Megan Kopp: right in front of just inside the inlet that is actually dredged every year as well, so this is some of the Channel volumetric change that you can see, on the Vo DS was the result of of dredging there is a human impact going on here but largely it's.
Megan Kopp: it's moving up and going in that guy that I know Danny fine.
Bryan Oakley: Thanks megan has a question, it may be more general than than just to you.
Bryan Oakley: But it's what I was just thinking about as well yeah what do we call this thing so lakes are non title so in a title system we call that a flood title Delta, what should we call that you know landward channel deposit because he see similar things in the Black Sea and other places.
Megan Kopp: Great question and i'm I don't have a great answer because the system is so unique so you don't usually find this kind of very barrier island looking system on a lake.
Megan Kopp: I do think that there are analogous to something like a.
Megan Kopp: Flood ty Delta, or maybe a third Delta, but I don't have a big term for it i'd be interested to know what what you think yeah.
Ilya V. Buynevich: I don't think we do either that's putting it out there.
Bryan Oakley: yeah I don't disagree with that oh yeah.
Bryan Oakley: I think it's it's certainly a.
Bryan Oakley: something interesting.
Bryan Oakley: All right, good morning.
Bryan Oakley: Sorry hold on guys i'm doing talking this morning.
Bryan Oakley: that's me but i'm ahead of myself.
Bryan Oakley: Alright, so i'm going to ask for help on this one if anybody can just chime in if you see this not working right with the chat.
Bryan Oakley: or just unmute and say something.
Bryan Oakley: Because this is our only pre recorded presentation it's mine I didn't want to risk messing something up with anybody else's i'm glad it's only me.
Bryan Oakley: And i'll just give you a quick context, this is largely coven work meeting we've been doing the field work since 2013.
Bryan Oakley: But this allows me time to kind of dial into the lidar because I had a lot less field work in 2020 that I was planning on, and I was also home, a lot more than my kids So this was something I could start working on largely on my laptop at home so.
Bryan Oakley: i'll obviously let it play it's going to be surreal watching yourself present and then i'll take questions at the end.
Bryan Oakley: So, if something works doesn't work and you can't hear me please let me know guys.
Good morning, and thank you for your attention today.
we'll be talking this morning about ongoing research down at the napa tree point conservation area.
That poetry is a welded or isolated barrier and far South Western Rhode island and particular focus of this work is on the response and then subsequent recovery of napa tree following sandy.
To me that's one of the most useful aspects of monitoring coastal systems it's not just how much erosion, we get during a storm is How does that barrier recover afterwards.
In a conservation area like napa tree where they focus on science based management this provided and still continues to provide quantitative data on how long the recovery takes from a storm like sandy.
and allows the managers to plan accordingly when there's a future event.
there's two additional presentations on that poetry today by my undergraduate students, one of them by Joe marsalis he focuses on the lagoon you'll see at the Western end of the barrier.
The other presentation by Gregory rodman focuses on more of the big picture century scale changes to the little narragansett Bay estuary and napa tree barrier using an 1800s or late 1800s that the metric chart.
So enjoy this presentation and be sure to stay tuned for the other talks enjoy the rest of the conference.
The napa to your point conservation area is located in Southwestern Rhode island right on the border between Rhode island and Connecticut at the confluence of block island sound and long island sound.
napa tree itself is the southern boundary for the little narragansett Bay estuary, which is where the pockets of river drains into which has a watershed of basically the southern one third of Rhode island.
sandy point pictured there as the small barrier island heading towards stonings and Connecticut is an interesting story it used to be connected to napa tree point prior to the 1938 hurricane but we're going to have to bypass that for time right now.
napa tree is a welded barrier connected to headlines at both the East and West ends the clumps and moraine forms napa tree point here at the West end.
And the watch hill headland at the East end well they're made out of a dynamic it's it's glacial till it's a mixture of silt a little bit of clay.
sand and gravel going all the way up through boulder sized the watch hill headland shown on the right is largely armored with both sea walls and resentments it's a pretty posh summer Community i've highlighted Taylor swift summer mentioned there for scale.
The barrier consistent a pretty typical single 40 and rich system, you see the East end has a fairly high for doing six to seven meters above mean lower low water.
The West end of the barrier is much lower average post sandy 14 elevation below four meters relative to me lower low water.
Why do we care about napa tree beyond being just a beautiful place to go do some fieldwork.
In attenuates storm and packs where the southern end of little narragansett bay and the Jason shorelines of stone unturned Connecticut and westerly Rhode island.
it's unmanaged and what I mean by that is it's got minimal use of San fencing and no beach replenishment.
Now why I say that showing you this slide it's a little bit ironic, but once you get away from the eastern end of the barrier, where you cross over what we call the big dune.
You don't see a lot of San fencing out on the barrier itself, and since 2013 they've largely phased out the use of traditional sand fencing.
Opting for split rail cedar fencing to direct people instead it's also essentially a closed system with minimal if any set of an input from adjacent areas.
It provides unique habitat for a number of threatened or endangered species, including piping clovers American oyster catchers and ELISE turns.
it's not unusual to see the last couple of years, doing field work in the late summer or fall three or four dozen American oyster catchers gathered around the lagoon on the Western side.
it's a conservation area, but it remains an important recreational area, with hundreds of visitors a day in the summer exceeding 1000 at times coming in, either by foot or by boat.
And as the manager Jana sassy likes to say her job is to keep napa tree from being loved to death, balancing the conservation, with the human years.
And superstorm sandy what we're focusing on with this presentation is the single most significant storm measured as storm surge to impact area since the hurricane of 1954 hurricane Carol.
In southern New England sandy was predominantly a wave and search event wind speeds peaked at 20 meters per second in a slightly off shore direction at the peak of the storm.
Pig storm surge was 1.4 meters above me and higher high water and offshore way fights measured at the block island buoy 50 kilometers southeast.
Of napa tree is about 9.5 meters we don't have reliable near shore data, except during tropical storm Irene on the Jason South shore they measured waves exceeding four meters in about seven or eight meters of water depth.
We assess the changes at napa tree using a combination of field and lab techniques, we have profiles measured with our tk GPS, these are done quarterly as well as after storm events.
We have digital elevation models that we can compare that were extracted from airborne lidar This includes.
which serves as our pre storm, we have 2012 post sandy lidar collected for the army corps of engineers 2014 and 2018 lidar.
From that lidar we extracted profiles every 50 meters along shore and from those profiles, we can pull out various metrics including profile volume dune volume during crestone height and as well as the various changes between those subsequent years of lidar.
field observations following sandy showed a mixed response on the barrier the western half the barrier was largely over washed.
And there was fairly significant deposition for wash over fans the eastern half of the barrier, where the students were higher prior to the storm some more frontal erosion more of a collision response.
In the parlance of salinger and others the dune CREST retreated on average four meters from its pre storm position with the maximum retreat of 13 meters in those transactions that the dune was basically removed.
the Far East and outside of the conservation area there's a set of beach cabanas the for doing that was underneath those cabanas was deposited in the parking lot and into a Jason watch a harbor during sandy that was subsequently excavated in return to the beach.
profiles extracted from the pre and post sandy lidar showed the change to the morphology of the barrier.
In both of these slides and all my subsequent images red represents erosion green represents deposition.
In this case, we see largely removal and retreat of the primary for doing we see deposition of a wash over fan on the base side, the left side of your image and we see berm deposition following sandy which was not a typical based on our work along the Rhode island South shore.
near the East end of the barrier, where the dunes are a little taller we see more of a scarfing response, the barrier narrows rather than significant deposition of any wash over fans.
The shoreline position measured as the last high tide swash in low wave energy photographs in June of 2012 and a field survey in June of 2013.
shows that the western half of the barrier and napa tree point shows essentially no change in shoreline position within the uncertainty of the methods.
The eastern half of the barrier, though, you see the red shoreline from 2013 is the land road of the blue 2012 shoreline in some places by as much as 10 to 12 meters.
By super imposing that pre and post storm lidar we were able to look at changes in elevation and calculate volumes.
Between the surfaces and read again represents erosion cream represents deposition and we see largely the left, half of the barrier the western half.
is showing some overwatch now the lighter Green is not continuous because i'm only showing changes greater than 20 centimeters plus or minus to remove the noise and some of the uncertainty.
You see less overwatch and wash over fanned deposition on the eastern half of the barrier, with the exception around a few of the smaller doing crossovers where we see some deposition on those paths.
The wash over fans near the western half near that lagoon are visible here in these 2013 oblique aerial photographs.
When we look at the morphology of napa tree as a whole, we see this trend of increasing tonight as we go towards the east really apparent on this graph.
This is the extracted dune CREST elevation from lidar data so taken right from the surfaces every cell every meter as you go along shore.
You see a general increase in tonight as you go from west to east and i've kind of drawn a line here at 1000 meters along shore.
Where you go from an average tonight of about 3.1 meters to about 3.9 on the east and relative to me and higher high water why I drew that boundary or why i'm indicating those averages there i'll show you in a minute.
When we look at the changes following sandy we see that West half of the barrier lowered considerably, and in some cases it went below the stillwater elevation of sandy suggesting that it was actually into the inundation phase, not just overwatch phase of salinger 2000.
Looking at the same area in 2014 and then 2018 we see the recovery of the barrier at the East end were largely exceeding the original dune height.
The West end we haven't quite caught up in in at least part of the barrier to being above the black line which would be 2011 but we're getting closer along much of the barrier.
If we think about the response of the shoreline, we can see it here in two different places we've got overwatch regime highlighted in cry.
For basically 1000 meters of the barrier the eastern half much more collision Oh, there are a couple places where they search penetrated via the walking trails the dune crossovers, however, that.
Was was pretty minor in the in the Grand scheme of things.
Monitoring the recovery from sandy began with profiles in the summer of 2013.
This animation takes us through all of the plotted profiles from 2013 through.
And what you'll notice is the increasing elevation of the backbone and the for noon, but I want to draw your attention to focus on the area around the primary for dune and the dune ramp under that highlighted area.
What you'll notice is, as we get towards 2018 2019 and specifically in 2020 is when we really start to see the development of the incipient dune in front of the primary for June, you can still actually see the dune scarf they're going back to sandy.
The barrier here has narrowed as you look at the little narragansett Bay or or bayside on the left of the image.
that's due to some erosion of the welded spit that used to enclose that small coastal pond on the West side of napa tree as that spits eroded away the barrier here is has narrowed considerably in the last seven years.
The recovery was well evidenced by a particularly windy storm event that was captured on two profiles 10 days apart in October of 2019.
Maximum speeds in this event exceed a 23 meters per second and the sustained winds for about a six to eight hour period occurred at a lower than predicted high tide.
Meaning more of the beach was exposed at low tide, but also a high tide and that velocity as well above the critical velocity for the grain size and even that's a slightly conservative estimate of grain size here.
This video gives you a little bit of perspective of what the conditions were like this is a pretty minor storm, as far as the The wave impacts, but you can see from the macula there was a pretty windy day getting sandblasted out in the field.
The profiles collected before, and then the day after that windstorm show the deposition of about three quarters of a meter cubic meter of sediment on.
The three profiles on the Center and eastern half of the barrier, you see, Burma ocean they're pretty typical for a small storm here about 10 or 11 cubic meters of sediment last.
But notable is that increase in in June volume on that incipient for doing that incipient for students continue to grow over the last year or so that we continue to monitor that.
We see a similar response that profile to you seen growth of the 14 and almost the same burn volume last last temporarily that's washers shame of salinger would suggest, of course, that's back within a few days.
Looking at the barrier as a whole from airborne lidar, and this was focused on the middle portion of the barrier between the groin and the Western headland.
We see no significant change in volume pre and post sandy that's probably due to the two week lag and the storm and when the post sandy lidar was collected.
The berm and the intertidal parts of the beach were largely recovered, so we don't see an overall change in volume.
But parsing it out by elevation we see a drop outside of the uncertainty in parts of the barrier above two meters and three meters here above nav.
We then see a steady increase in the higher portions of the barrier in terms of volume.
Both above two meters and above three meters and right on the edge of the uncertainty for above four meters of elevation.
you'll notice, not much change between 2012 and 14 There does seem to be a several year lag here before the vegetation, particularly on the front of the.
eroded for dune recover took three or four years for that vegetation to really come back in a big way, and that is trapping now that sand on the incipient for dunes, we saw in that October wind storm of last year.
So I think i'll leave it there for time i'm just over my 15 minute, mark you can contact me with any questions about this obviously my email address or social media, this is ongoing work we're still working down at napa tree still examining how the barrier response to the storm events.
And i'm happy to chat about it, if you have any questions i'll give a final credits here to this picture taken by Ayla fox.
shed light creative she's done some video work down at napa tree for various documentaries, but this is a pretty pretty beautiful shot to end with, so thank you for your interest and enjoy the rest of the conference.
Bryan Oakley: Right, I did leave myself a ton of time for questions because I messed myself up on.
Bryan Oakley: The set up.
Bryan Oakley: Mike do we see the beaters there, there are Beatles on on certain ones in the northeast, but I have not heard of any unnecessary, but there are people looking for those and studying those that's an interesting one, to look for those really endangered.
Bryan Oakley: beetle.
Bryan Oakley: And thanks for the visualization comment Mike any other questions we have a minute or so until we go with our next talk.
Bryan Oakley: I will also be around during the break So if you fire up any questions or think of any let me know, then.
Bryan Oakley: Alright, our next speaker I just lost my.
Bryan Oakley: My iPad with that screen on it, but our next speaker is hayden attacker and his co author is is Elio so hayden go ahead and share over your screen.
Hayden Thacker: All rights, hopefully, everyone can see as well yeah so my name is hayden bakker i'm a first year masters student at temple university and he's pushing it a little bit today and.
Hayden Thacker: Take a look at the subsurface of the actual or specifically some laps and relations we've done of sea turtle passionate emergence Tokyo clutter in the back door.
Hayden Thacker: And what we mean by GEO clutter is 3D anomalies in the sand, whether it be physical or biogenic.
Hayden Thacker: You can also consider anthropogenic effects on the normal sediment fabric, do you think of a busy beach day and people throwing trash on the beach and making sand castles taking calls all this stuff can be subsequently buried and preserved in the subsurface for.
Hayden Thacker: Potential clutter when you're trying to use GPS and coastal environments and other things such as.
Hayden Thacker: crowd burrows or.
Hayden Thacker: Our we're looking at here with sea turtle nesting structures storm events roots from vegetation and collection of what a material all this stuff can be buried in be.
Hayden Thacker: Potential clutter when you're trying to use GPS environments so GPS has a rapid continuous way to.
Hayden Thacker: Not and basically visualize what's going on the subsurface so you have a an antenna that sends electromagnetic pulses down into the subsurface and.
Hayden Thacker: These in waves interact with the different media and the subsurface differently depending on what the dielectric constant of.
Hayden Thacker: of whatever anomaly or media, you have in the subsurface So if you look to the right here in this raider Graham, this is an example of white space and gdpr where.
Hayden Thacker: You can see the normal subnet fabric here to the left, but the second you hit this white space, it shows a pretty clear contrast to the normal hosts that have them.
Hayden Thacker: So we're doing some simulated sea turtle hatch the emergence of the lab.
Hayden Thacker: Using both a time lapse and a time triggered mode and my time labs that's imaging before the Senate disruption and then imaging after to see the changes in the subsurface from this process, and then the time trigger mode is something really exciting that we're even working on.
Hayden Thacker: Getting getting into the actual field, and this is actively imaging through time in one spot, while the sun and disruption is occurring.
Hayden Thacker: And this is all has implications for discerning these structures from other can fill structures in the.
Hayden Thacker: In the modern and and the fossil record or in the rock record and potential conservation efforts as well, so being able to locate these actually are these sea turtle mess and protect them to get those toxins out to the water it's relatively.
Hayden Thacker: Real can be relatively hard to find the nesting structures so when I say, new technology if you're not familiar with the terminology of the interaction.
Hayden Thacker: With organisms with the substrate and then nia with knowledge it's just that, but in the modern.
Hayden Thacker: And the Left column here is showing the only known fossil nesting site for sea turtles and if you begin to think about that that's kind of strange because.
Hayden Thacker: We know even just in the modern sea turtle nesting structures are relatively abundant and before anthropogenic effects on their population numbers.
Hayden Thacker: There be potentially millions of views yearly get we only have one preserve site that's been positively identified so it's gonna be due to a couple of things potentially.
Hayden Thacker: Maybe they're under represented confusion with similar kind of steel structures or this might be some preservation.
Hayden Thacker: Preservation thing that isn't that isn't aligned needs to be preserved in the rock record.
Hayden Thacker: And the general morphology here, you have the body fit and you have this covering pit here to the right and we're we're focused right now with the Chamber.
Hayden Thacker: And you can directly compare the fossil one with what's going on the monitor and, and this is kind of our goal with the gdpr us where you can see, you know these trail waves and.
Hayden Thacker: The Cone shaped depression in the subsurface for the a Chamber is, and this can be represented as well with gdpr where you have this body pay right here, and the depression, where the Chamber is we actually do have some data.
Hayden Thacker: that's been previously collected on this, so my advisor helps them conservation people locate a nasty previously and this had the added benefit of giving us some preliminary data for the study, where you can see.
Hayden Thacker: well represented in the radio graph is this Cone shaped depression, as well as the body pit was able to discern from this.
Hayden Thacker: So our major area of focus right now is this this aspect of the hashtag emergence where they're coming out of their eggs actively disrupting the sentiment at the surface and then.
Hayden Thacker: everything that happens after is it still considered part of the technology, but not really the major focus for us right now.
Hayden Thacker: And a major thing to consider when imaging and coastal environments, especially with something like this is the moisture content at depth.
Hayden Thacker: Especially as you get into saving water at depth, you can run into some issues with cpr because the conductivity of salt water.
Hayden Thacker: makes it so that the the electromagnetic waves kind of scatter and attenuate in you're restricted to only a certain depth our our area focus right now is this upper layer of dry sand, we can still do some imaging down here in the damn stand, this is.
Hayden Thacker: As I showed before with the already collected data, but the major area focus right now is the fact of sudden destination in distracts and at the top, with a future potential damage Stan trials as well.
Hayden Thacker: And, before getting into the actual experiment design here, I wanted to give some general terms as well, so.
Hayden Thacker: When when you're using GP are specifically looking for anomalies in the subsurface the best case scenario is having this high dielectric contrast.
Hayden Thacker: And this can be due to either what's your changes or, if you have void space of depth and what this means is that the host sentiment around it and whatever anomalies that you have in the subsurface of different enough daltrey.
Hayden Thacker: dialect dielectric constant that you have a high contrast and they're relatively easy to discern in the greater Graham.
Hayden Thacker: But this study is going to be focused on a low contrast matrix and a dry sand with a relatively small target and we're really interested in seeing whether or not you can actually you can get good results when when looking at on a small scale minor changes to the dielectric constant.
Hayden Thacker: So for the for the live set up, we have these bend on here and we first filled the bottom, with the layer of sand and then placed our target and our target consisted of.
Hayden Thacker: A balloon that was filled out here with air fluid or sailing and the goal of this was to try to mimic a sea turtle hassling and.
Hayden Thacker: We tested to a 12 contest line covered in tape to protect it from potential friction with the sand and we didn't want it to go from obviously and then after it was placing their we buried again with another layer of sand over top of it.
Hayden Thacker: And then did are different gpo runs over it so with the time lapse mode also referring to this continuous those are runs one, two and three, so you first go over the the length of the box when the targets first very to get your initial reading on.
Hayden Thacker: The general sentiment properties, as well as looking at the target within the subsurface and then as we're pulling out the target we.
Hayden Thacker: Actively image in one spot through time to see that the act of southern defamation as it's being pulled out, and then the final run goes over and see if you can still see that some information.
Hayden Thacker: After all, after it's going to be pulled out.
Hayden Thacker: And this is here's a few diagrams that probably convey it more clearly where you're doing step, one in three.
Hayden Thacker: being connected with the time lapse mode, but you also have this intermediate mode of the time triggered that we're really excited about where you get you get to look at it exactly what's happening in the subsurface through time.
Hayden Thacker: And this aspect, as well as really interesting to look at, because when you have a dry stand like this, you wouldn't expect.
Hayden Thacker: there to be much defamation after pulling out the target because you'd expect this the same to settle back into the void space that was created i'm like if you had a website and then.
Hayden Thacker: But as we find we ended up being able to see this defamation subsurface after after the fact, so this is our first initial.
Hayden Thacker: run over here and the time lapse mode, this one is with the sailing balloons this would most closely resemble an actual sea turtle hassling.
Hayden Thacker: But you can look at the the target in the subsurface pretty easily with this if you're looking at the general pattern the fabric above it and then below right here, where you can be targeted it's easy to spot, but right here is what was really exciting about this.
Hayden Thacker: experiment because we're able to see very clearly these basically a column, where we pulled straight up and had the sediment fill back in there, but it's still discernible with gdpr so that's really exciting and unexpected.
Hayden Thacker: And the time triggered mode as well, which was really interesting, where we had you can see here you just have the general noise before and after imaging and a note, but the X axis is time now it's a distance, where.
Hayden Thacker: You can see at the beginning of the the pulling up of the target, you can begin to see this.
Hayden Thacker: act of defamation, the subsurface all the way up until when it's emerged, and you can track it through time as it's moving up in the subsurface and.
Hayden Thacker: Then, finally, after we do that we can get the time lapse and see what the end result of this was.
Hayden Thacker: And the grand sizes, a little little different at depth between our first layer of sand and then after we get the target of this was due to some like this the minor so fraction nation when pouring the sand in removing some of the fines just something to note with this.
Hayden Thacker: But this is some implications for scaling this up to other.
Hayden Thacker: common structures that you might find both in the modern and in the rock record, so this clap clap stakes chain plastic change Chamber will be similar potentially to something like scour or even like a shallow grave in the subsurface in.
Hayden Thacker: The end goal here is to potentially be able to discern these from these common structures as well with the body pit being similar to that of something like a search channel, or maybe the shallow and let and.
Hayden Thacker: to really be able to get an accurate look at the subsurface morphology of these will likely have to get some 3D images taking multiple translates across and stitching it all together to get 3D images to really be able to discern this.
Hayden Thacker: But we do have plans to do this in person, potentially, in the future, going to the outer banks and basically running this entire thing, but with live field conditions so.
Hayden Thacker: Setting up like a stand above the active sea turtle happening emergence and imaging live well it's happening and then going back over and maybe getting a 3D image of of.
Hayden Thacker: The end result after all of the happens limericks, but this is a non intrusive method here and we're really excited to be able to potentially get on the field and do this and see how it compares to our lab data.
Hayden Thacker: And this can also be extended to other environments beyond just coastal environments, so this specific slide is showing.
Hayden Thacker: Something that's really similar to what I showed with the time lapse mode, but this is still time triggered So you can see here, you have the normal subnet fabric and then.
Hayden Thacker: someone's hand and stuck a hand in the subsurface causing this disruption, you can see the the.
Hayden Thacker: wiggly lines here where it flushes now on the subsurface and then pulled the hand out and created.
Hayden Thacker: This this pocket of air and the subsurface and, finally, when everything's settled back in you can see the.
Hayden Thacker: The end result of this destination in the subsurface just like that final image with our time lapse mode where even after removing the the target and everything subtle, you can still see the evidence of this happening in the raider Graham.
Hayden Thacker: Alright, so wrapping everything up here.
Hayden Thacker: So GPS Bible school for continuous and real time managing it back for anomalies above sailing attenuation so, and this is really important to consider using GPS or.
Hayden Thacker: In in these coastal environments, as you can you can discern a lot of information, but you are restricted at depth, which creates a good opportunity to use high frequency GEO radar and these.
Hayden Thacker: coastal environments because you're not going to be able to image that depth with the lower frequency but increased depth at that gives you, but you will be able to see high resolution data directly.
Hayden Thacker: Under the subsurface and then we'll likely also need to take some 3D trans sex in the field to correctly discern what's going on and get a overall view on the general morphology of these nesting structures.
Hayden Thacker: And, and the time trigger mode is also really exciting where we'll be able to get a live look at how are our lab data compares to active segment defamation in the field with these T turtle athletes, and this also has some implications for conservation efforts so.
Hayden Thacker: Being able to locate and protect these structures is something a lot of people are concerned with and GPA or might be a pretty useful tool for them.
Hayden Thacker: Being able to look in the subsurface and.
Hayden Thacker: Directly see where the eggs are present in the picture.
Hayden Thacker: All right, and I also wanted to give a quick Thank you to all the people who have.
Hayden Thacker: worked towards this research in the past and building upon this in our lab and thank you to Andrea served as well undergraduate research assistant, who played a major role in getting this project going and will continue to play a major role, thank you.
Bryan Oakley: Thank you hayden was great talk and that's a really interesting application of that high frequency and high resolution cpr and that was interesting we have any questions for hayden we've got about four minutes so.
Bryan Oakley: Mike asked what's the finest resolution you can achieve i'm asking, because we have a lot of questions about tiger beto beetle borrows on the beach race there's a tongue twister for you, do you think you could see those are or are they too small.
Hayden Thacker: Not likely given you can you can get to pretty small scale, especially with the the resolution we're using right now 2300 but you're restricted to add say.
Hayden Thacker: Mostly mammal to macro and vertebrates right now, as far as the resolution I wouldn't expect to be able to see that fine of scale of structures, but it would be cool.
Bryan Oakley: Any other questions for hated.
Bryan Oakley: Mike said thanks for the answer.
Bryan Oakley: How how non invasive could you do this hayden around active turtleneck because obviously that's a particularly vulnerable part of the beach when the turtles are there, how would you go about doing that you know, in a non invasive non you know perturbing the turtles way.
Hayden Thacker: yeah so you can set up like maybe a box or something similar to how we have this setup where you don't actually need to be imaging directly over on the surface above these.
Hayden Thacker: These nasty you can instead have it lifted up above and do the run and you can go pretty quickly through the air that'd be the gap between that you still get some high resolution data well, so you wouldn't have to directly measure on these nasty you'd be able to.
Hayden Thacker: not disturb them.
Bryan Oakley: awesome Thank you any other questions for him.
Bryan Oakley: Oh, do you have a modern photo of alien not those during his teen years.
Hayden Thacker: i'll send you something you know.
Bryan Oakley: Oh, that was a nice.
Bryan Oakley: sands of time for all of us all right, thank you, and that was a very, very interesting talk, I have not used to PR and in a while so rose asks how long of a time, can you monitor, could you measure through a nesting season, or is this all short term work.
Hayden Thacker: Oh, with the scale that we have we wouldn't be able to do that, but I mean.
Hayden Thacker: You get a you'd have a ton of data if you were actively doing this, you could do a scenario where your imaging maybe twice a day, obviously, or you can do if you live near the environment, you go out and continue to image, but you you wouldn't likely.
Hayden Thacker: see a whole lot of changes in the subsurface through on that timeframe, because once the eggs are down there until they hatch this not going to be a whole lot going on other than maybe prediction or.
Hayden Thacker: Any changes in the moisture but if it could be possible, not with not with this study that we're doing but that could be set up.
awesome Thank you.
Bryan Oakley: So we got about a minute and a half to our next talk so i'm going to hold to that just so we can stay on time.
Bryan Oakley: i'll just throw out there that the after the next talk, which is it's going to be justin.
Bryan Oakley: schaller talking about Virginia we're going to have a break, scheduled for 20 minutes and so that'll stop started about 1005 I started 15 minute break at 1020 we'll come back for posters.
Bryan Oakley: i'm not going to plan on going anywhere during the break so if anybody has questions for any of our speakers that might be a time to ask them, I know I saw a couple that didn't get answered.
Bryan Oakley: You know, we can just kind of hang out have an open discussion for those 15 minutes everybody else can get a coffee or do what they need, and then we'll we'll come back for the posters at 1020.
Bryan Oakley: justin you can go ahead and share your screen, we got about 30 seconds or so.
Bryan Oakley: i'll just say I haven't figured out how to let them at the conservation area napa tree, let me bring out a geo probe I haven't quite gotten to that point yet, but maybe someday I will.
Bryan Oakley: All right, i'll let you get going here justin so our next speaker is justin schaller i'll let him introduce his his host of co authors and he's going to be talking about.
Bryan Oakley: sediment systems in the northern Virginia coastline let's go ahead justin.
Justin Shawler: Great Thank you Brian yes i'm going to share with you some research from my PhD so i'm just a taller and a PhD candidate at the Virginia Institute of Marine Science.
Justin Shawler: As well as a coastal scientist for the state of Delaware but this talk whole focus purely on the Virginia coast and I was able to maybe squeeze in the idea that.
Justin Shawler: Because northern Virginia coast it's appropriate for northeastern section of GSA.
Justin Shawler: But i'm going to talk about the evolution of what amounts to a large sand sink on the Virginia coast, as well as offer some implications for regional sediment transport.
Justin Shawler: My co authors on the talk are Chris Hein at Femmes chloe up era and Mina robbins who were undergrads at films and now are already off on bigger and better adventures are about to be and then last but certainly not least Mike fenster at randolph macon college.
Justin Shawler: oops I only my mouse does not want to advance there we go.
Justin Shawler: As well before I dive into the talk, I want to acknowledge our funding sources, including Virginia sea grant and funds from the Commonwealth of Virginia.
Justin Shawler: And some folks at the eastern shore lab who have made this work instrumental Jen connell and Yiannis Georgia as well, who played a big part in the field at the lab as well.
Justin Shawler: And then, many, many lab volunteers and our Community volunteer john harding who always seems very, very happy to come out in the field with us, and he tells us that it's a good time, at least, even if it's a lot of work, the motivation for this talk is the idea that, if we look globally.
Justin Shawler: In particular strand planes so mainland attached barrier features are excellent archives of coastal change and various studies have you know extracted sea level change records from.
Justin Shawler: barrier features, as well as records of changing storminess.
Justin Shawler: And things like sediment supply and wave refraction patterns as well, and how those changed through time, of course.
Justin Shawler: And our question becomes well can provide additional barrier islands and spits also record.
Justin Shawler: Coastal records of coastal change and certainly there are folks who have investigated this, including at some of the.
Justin Shawler: including some of the sites that I show on this map, I will say that some of the sites that i'm showing here are all of the sites, perhaps have a southeastern or Gulf coast bias, and here I am at northeastern GSA but.
Justin Shawler: ignore that maybe and think about how many potential archives, there are on the US.
Justin Shawler: Eastern Gulf coast's and so, if we can extract good records of coastal change from these systems, they can tell us more about the overall coastal system that they're in and help us understand future change as well.
Justin Shawler: So let's dive into some details about the Virginia coast.
Justin Shawler: The Virginia coast, has a net sediment transport direction of north to south, and so you end up with this long linear we've dominated.
Justin Shawler: barrier St island to the north and to the south, you have shorter mixed energy barrier islands that Catherine spoke about and of relevance to what i'm talking about today is this feature called the arc of erosion, made up of.
Justin Shawler: Southern wallops as well as as a woman and pumpkin and cedar islands, and this is a.
Justin Shawler: area or section of the coach that has shoreline offset compared to features, to the north and features, to the south, so paramour island immediately to the south and.
Justin Shawler: acetate island which i'll be speaking about today, and so the blue box is shrinking to England and the surrounding barrier islands.
Justin Shawler: The oldest and landward most feature of the the three that i'll speak about today chincoteague island and that's a relic program additional barrier island just landward of that is.
Justin Shawler: What is locally called lighthouse Ridge or acetate point and so that's a series of relic read curves from prior spit building on St island.
Justin Shawler: And there's a narrow isthmus so this thin strip of land that gets frequently over washed.
Justin Shawler: And then the the next and currently active reserve spit locally, referred to as fishing point or Tom scope hook our food choices fishing point during this talk.
Justin Shawler: And then wallops island, which is an actively programming barrier island, at least on its northern end Mike fenster can speak to you all about the erosion problems down South where where NASA wallops mean rocket launch facility is.
Justin Shawler: So let's look at the last 30 years i've changed at these sites and again we've got this sort of north, south trending chincoteague inlet in the Center of the imagery and then we've got our active fishing point spit and the pro grading wallops island.
Justin Shawler: So you can see that this a fairly dynamic system.
Justin Shawler: And we can see how quickly it's building out, which suggests that it functions as a fairly large sentiment sync.
Justin Shawler: And the goal of this work is to actually quantify the volumes of sentiment trapped in the system, both over the longer record the the centennial to millennial record as well as shorter term change over the historical record.
Justin Shawler: So, to get this question, we turn to a variety of field mapping tools so.
Justin Shawler: auger shallow auger corps to retrieve samples for optically stimulated luminescent so looking at the last time sand grains and those ranges saw sunlight.
Justin Shawler: We also took a number of GEO pro course so getting down to.
Justin Shawler: About 24 meters see between 20 and 24 depending on the site and we're able to also turn into.
Justin Shawler: Some of the past literature from the area and integrate in some older jet wash corps auger drill cores and even some usgs testwell logs.
Justin Shawler: And then we also and I think hayden a lot for for setting me up so well we're also turn to to ground penetrating radar to further resolve the subsurface.
Justin Shawler: So let's dive into some of those results right there's an example of that field sampling of optically stimulated input for optically stimulated luminescent sampling right, so we just do the.
Justin Shawler: 30 fieldwork and then send it off to an external APP for analysis and what that gives us is a good approximation of the age of individual bridges that are preserved in the morphology of the system.
Justin Shawler: And so what we see is that there's this as we move across the island right we integrate in those rsl dates we integrate in.
Justin Shawler: Historical shorelines and we see that there's as expected this young trend from.
Justin Shawler: The landlord most edge of chincoteague island to the sort of southern active portions of fishing point.
Justin Shawler: And while up straight so that suggests, of course, shoreline propagation through time and we can see further evidence of that in ground penetrating radar we have our own interpreted.
Justin Shawler: Competence rating radar line on top, and are interpreted line on the bottom, and in that interpretation, we see evidence of cross your presentation, including of course see we're dipping.
Justin Shawler: reflections and then just above that we interpret some alien sedimentation in the form of one of those preserved for dunes, with some overall more chaotic reflections.
Justin Shawler: i'll just show you an example of the graphic analysis that we did because they're there are a lot of course that we were able to integrate in thankfully.
Justin Shawler: And so, this is a an example of the cross or the sort of overall cross or from from landward to see where it of the system, so it starts on chincoteague island and crosses over to acetate island right in there just separated by this fairly narrow back barrier channel.
Justin Shawler: And what we see if we started the base of our strata graphic sequence.
Justin Shawler: We interpret the very base there's this shallow marine.
Justin Shawler: place to see an age so greater than probably greater than 120,000 year old surface or your layer excuse me, and this is very glock kinetic and is clay and Shell dominated.
Justin Shawler: Just above that we have a finding upward sequence that are in most cases, finding upward sequence that we interpret as place to see an estrogen so the base of that is course and even some pebble we interpret as being more fluidly foo foo really influenced, and then it.
Justin Shawler: transitions to something that's got indications of Title influence finer grain deposition pleasure and lenticular bedding and just above that we have a transitional piece or kitchen this sort of dark brown layer and that dates to about 6000 years ago and we.
Justin Shawler: We use that as evidence of initial Holocene deposition in this area, on top of that, we have the rest of our back barrier deposits.
Justin Shawler: Minor amounts of salt marsh repeat, as well as the sort of muddy back barrier sentiments that we would expect along the MID Atlantic coast.
Justin Shawler: That, of course, extends further landward of chincoteague and wallops but chincoteague and meanwhile ups both over lie that back barrier sedimentation as well right so some evidence there of obviously landward retreat over top of those back barrier features.
Justin Shawler: And then we get to our evidence further evidence of shoreline procreation, so those sort of see where dipping things that you see your or based on gdpr but are certainly artistic.
Justin Shawler: Artistic license was used to there right but it gives us this sense that we have this shore face and then and then barrier island sediments.
Justin Shawler: So example of stratigraphy and now we we integrate that whole data set and speak and speak to the evolution of the system so we've interpreted and evolutionary model.
Justin Shawler: For the coastal system there and at each stage of the evolutionary model i'm going to try to speak to settlement transport pathways that we can infer as well as the volumes and fluxes of sediment that are trapped through time.
Justin Shawler: And so we know that initial Blackberry deposition began about 6000 years ago in the chincoteague and let system and that's.
Justin Shawler: typical of what we see along the Virginia coast is that we get the the first evidence of back barrier deposition and most these systems about 6000 years ago that's, not to say the barriers weren't just further offshore prior to that.
Justin Shawler: But that evidence of initial Blackberry deposition or onset of back period deposition these sites is coincident with the decrease in.
Justin Shawler: The rate of sea level rise along the coast from two to one and a half millimeters per year and during this initial phase, this stage one is i've called it for about 6000 years ago to 2200 years ago.
Justin Shawler: The behavior of the system is transgressive, of course, we know that there could be could have been passed periods of you know.
Justin Shawler: barrier stability or even provocation, but the the net behavior is transgression driven by overwatch the title and let processes and during this time, we have sort of overstepping of those back barrier deposits and partial erosion of those features on the shore face.
Justin Shawler: Then about 2200 years ago chincoteague island stabilized and it stabilized slightly landward in for both acetate and, while a swipe stabilized is actually a little bit unclear.
Justin Shawler: In other parts of the Virginia coach there's strong influence of the underlying topography, the antecedent geology has a strong influence on barrier stabilization and sort of pending effect.
Justin Shawler: Indirect typically but we don't see evidence of that here on chincoteague but, nonetheless, would it sets up by being slightly land where did these other two islands is a complex sediment transport scenario where.
Justin Shawler: In let's play a role waiver fraction around southern assa tea, as well as the title belt as.
Justin Shawler: causes sediment transport that results in the onshore migration of bars and we see evidence in the original alignment on chincoteague creating this sort of fanning effect where which, which suggests that there's this shifting noodles down.
Justin Shawler: Somewhere through time on Central chincoteague and that middle zone generally shifts net to the south over time.
Justin Shawler: And it's very similar to what we see on modern northern wallops island today.
Justin Shawler: So from 2200 years ago to about 400 years ago we have this.
Justin Shawler: Net procreation, of the system right i've broken it up in a couple little phases there just based on our cell dates, but.
Justin Shawler: The general idea is that we have net procreation, of the system and during this time it traps upwards of.
Justin Shawler: 80 million cubic meters of sand at a rate of 45,000 cubic meters for an average rate of 45,000 cubic meters per year i'll provide you additional context for those numbers as we move along with keep their relative magnitudes in mind, as I move forward here.
Justin Shawler: Then about 400 years ago.
Justin Shawler: assa T island grew seaward of chincoteague but then it didn't start to elongate or program or we don't have a record of that and we infer that it's related to the.
Justin Shawler: Opening of inlets up drift over this same time period there's a there's one in open a federally immediately up drift from about 1755 to 1827.
Justin Shawler: And what that does is it results in the retreat of wallops island, but because the shorelines not programming.
Justin Shawler: On acetate instead there's time for this tall for doing to grow it, and so we see this eight meters tall rage that's that lighthouse rage that I mentioned, when I showed you the map earlier.
Justin Shawler: But those inlets close.
Justin Shawler: launcher transport increases are sort of southerly transport of sediment increases and what happens is that assa tea table to build out, so we have the.
Justin Shawler: first set of records to the north, and then we have that isthmus build out and now we've got this active southern end of the island that's building out and that results in the.
Justin Shawler: About 120 million cubic meters of San being trapped in the system at a rate of 660,000.
Justin Shawler: cubic meters per year so much higher the volume is a little bit higher, but the the flux is is is significantly higher compared to the permutation of chincoteague island and.
Justin Shawler: I think thats related certainly did informational processes here, here we have pretty rapid elongation of.
Justin Shawler: A spit compared to a fairly slow progression of a barrier island and what we see on wallet is consistent with what we see.
Justin Shawler: or in for about the past from she could take where we have 7 million cubic meters of sand trap, but it's doing so on a at a rate of about 42,000 cubic meters per year so very similar what we say on chincoteague in terms of the rate.
Justin Shawler: it's a different way of looking at this we've taken the evolutionary model and tried to quantify based on barrier thickness and barrier area.
Justin Shawler: volumes show here, as well as fluxes of sand traps we've got the netflix of San trapped in hundred thousand meters cube over time that orange arrow points out.
Justin Shawler: Where the X axis scale kind of shifts so that we can refine the historical record, otherwise you know the.
Justin Shawler: time she took to build out as this so long that we wouldn't better refine the historical record very well on the same graph.
Justin Shawler: So we have these time varying controls on longshore transport we go from.
Justin Shawler: Slow net San trapping at chincoteague to those inlets opening and the flux is potentially trapped in those elements is relatively high compared to what was feeding chincoteague.
Justin Shawler: Then acetate the spit as well as the first set of records on acetate as well as fishing point.
Justin Shawler: or trapping much higher netflix's of sand, so we we have this elongating spit that's basically a greater control on long term transport and the inlets and those are greater control than.
Justin Shawler: Professional barrier islands and so altogether, while ups and messaging and the modern system or over the historical record of trapped about 60 to 100% of estimated long short transport and those estimates come from a few different engineering studies.
Justin Shawler: The implication of all this is that, at the same time, there were is the historical growth of acetate started you start to see this rapid.
Justin Shawler: rate of growth and High Flux of sediment trapped it's coincident with state shifts on down drift islands and shift from a system wide range of.
Justin Shawler: Five meters per year up to seven meters per year and much higher even on individual islands.
Justin Shawler: But i'll note that San trapping is just one of many factors such as sea level rise a sand for sure face wave refraction around the same feature southern island.
Justin Shawler: and potential changes in storminess i'll leave you with these conclusions, but i'll go ahead and stop now that there's time for questions.
Bryan Oakley: Thanks justin.
Justin Shawler: they've.
Bryan Oakley: got about a minute and a half or so for questions if anybody has any for justin.
Bryan Oakley: i'll i'll just say it's an interesting talk two things come out of all these one is I get to teach myself how to do, Google or attention because you guys make such cool.
Bryan Oakley: visualizations with all that stuff and the other is i'm always partial to settlement starks your faces being important because the one I work on it's really, really sad him and starve so.
Bryan Oakley: I was glad to see that in there any questions for justin I.
Ilya V. Buynevich: Have a quick one great job you think, so this is sort of wave dominated maybe less wave dominated in the past, maybe more but what's the, what do you think is the relative.
Ilya V. Buynevich: importance of inlets let's say along the asset ego sort of trapping sediment I mean they're obviously no groins back then, but inlets may have trapped some sediment.
Ilya V. Buynevich: You had a way to bypass that inlets So do you think that more efficient than, say mixed energy setting a trumping the symbol of itself or less efficient.
Justin Shawler: So really great question and one that Chris and I seem to text each other about maybe once a week great because it is such a fascinating topic and i'm really i'm really interested in flood pedal built us right now on sort of like the thing that's got me thinking a lot and I, so I think.
Justin Shawler: One interesting thing that comes to mind for a flood title delta is.
Justin Shawler: Now, how rapidly does it actually build out right is it just sort of this one shot over a fairly short period of time where you're where you're really getting that that flux of sediment.
Justin Shawler: Or is it building out over a longer period of time.
Justin Shawler: And how does that thing compared to trapping at an EP titled delta rightness entitled delta's tend to be much bigger.
Justin Shawler: On along these mixed energy barriers, where you have a long time for the end let's to form and the title delta's to form and start to influence at least sedimentation on the adjacent beaches, so I don't.
Justin Shawler: it's not a good answer, maybe, but it certainly when i'm a question i'm thinking about as well, and one, but I think is really important, because I do think, both in the wave dominated in the mixed energy setting that these these elements are important controls on sediment transport and.
Ilya V. Buynevich: This is a good place to test it because you do move from wave dominated to more mixed.
Ilya V. Buynevich: identity, so they affect i'm traveling sentiment and then bypassing is different, but it's like some of the most complex coastal compartments on the east coast so good luck was more research.
Justin Shawler: yeah so I wants to do another PhD with with Chris it'd be a great PhD topic that's for sure awesome.
Good.
Bryan Oakley: Thanks justin um so we're at 1005 guys, this is going to be our break time for 15 minutes or so, when we come back it'll be the poster session which, in the virtual conference is.
Bryan Oakley: I will put the slide up on the screen for it press play on the pre recorded introduction hopefully you've had a chance to look at some of the posters.
Bryan Oakley: I looked at him last night I was playing around on my iPad for for quite a while looking at him missing really good posters out there, so.
Bryan Oakley: we'll be here i'm not going to go anywhere just logging off and messing something up, but if anybody had any questions for any of the speakers from the first session or first part of the session, you can have discussions as you want now.
Bryan Oakley: It was all self and diligently ask your answer your question, yes me.
Bryan Oakley: Right at the end of my slides rose asked if I expect a similar impact on that barrier between the West and East, given that the western parts recovered i'd say yeah probably still would, at least in smaller storms.
Bryan Oakley: You know, big cat to hurricane like 54 or larger it's all bets are off because.
Bryan Oakley: I don't put a lot of faith in the 540 year old female for the cross section of the doing a bunch still water but almost none of that the exception of one piece of the dune is above that threshold so which we saw and it's another.
Bryan Oakley: set of slides I think might have been what I was going to talk about last year they canceled one but i'm working on a paper on that, looking at this store sure like change and 38 completely obliterated an overwatch the entire barrier.
Bryan Oakley: In smaller storms extra tropicals and kind of sandy type events which aren't super high on search.
Bryan Oakley: yeah you probably continue to see that response with more overwatch on the West side and more collision on the side until the.
Bryan Oakley: Eastern dunes get a wrote it enough to their their overwatched That would be my guess it's an interesting spot to maybe even run a model and i'm not a model or but there's certainly.
Bryan Oakley: Because it's such a weird little closed system it's it's certainly an interesting one to plug into a into a model.
Bryan Oakley: um so my cast a really good discussion question, what is the Community think of using Google earth to do global scale desktop analysis and barrier island development.
Bryan Oakley: they'd like to submit a manuscript soon, and he doesn't have enough bandwidth to run his camera so he's he's not there to to smile and asking himself What do people think about that.
Bryan Oakley: And i'll jump in I think i'm good.
Alice Staro: With colors can be useful, but the problem is always this resolution and the scale right.
Alice Staro: So if you want to show what they think I did, and also just indeed it's like let's see how how much does it change the.
Alice Staro: way it's useful.
Alice Staro: But you definitely need higher resolution imagery if you want to do detailed analysis I believe so yeah.
Alice Staro: High resolution imagery are problematic because they are always provided by private satellites, so you have to pay for them.
Alice Staro: Why lanza and then.
Alice Staro: hire a smaller resolution.
Alice Staro: imagery like optimal the sense on Sentinel available, so if your barrier island is can each the feature really interesting.
Alice Staro: At least 30 meters okay that's okay for using lancer and then it's kind of okay using Google Earth.
Alice Staro: that's my my opinion, so I did, for example.
Alice Staro: A couple of analysis with remote sensing imagery and so on, and it was about to give up for my study side because it was impossible to use it with work on it with lance that but it, for example, work perfectly on.
Alice Staro: The data lake but it's not about an island, but it's not as huge as an ocean and you could see the feature anyway, so if you're ready run sorry, it is also another problem with.
Alice Staro: remote sensing and Google or is that if you have a lot of your settings.
Alice Staro: Your images gets a lot of noise because tend and buildings have physically almost the same spectral signature it's very hard to distinguish them.
Alice Staro: So I took a lot of time sorry but.
Alice Staro: In short.
Alice Staro: it's Okay, I think, to use Google earth to do a quantitative studies like okay these places moving in this is stable, but if you wanted a quantitative study on that you need to have.
Alice Staro: A way to distinguish a lot between European data Center and then hybrid solution.
one.
mfenster: Thank you very much, I guess, I would I don't not trying to defend the use of the data set, but just to clarify it's.
mfenster: a snapshot analysis it's not a time series, and in order to to capture it and be able to compare apples to apples, we have to find photographs from synaptic time period and it's not easy in Google earth but.
mfenster: it's also very difficult to quantify the uncertainty and how you define a barrier find barriers, but it does raise some really interesting questions about what is a barrier island, I mean we.
mfenster: are lots of things that you see in Google earth image images that look like barriers but aren't and that's the scale we're kind of at and it's not a time series, but I do appreciate your comments and thoughts on that.
mfenster: You certainly know some of the complicating factors and trying to do an analysis like that.
Bryan Oakley: I don't have a lot of personal experience, but I think the uncertainty, you mentioned is the.
Bryan Oakley: biggest challenge, particularly if you're trying to quantify.
Bryan Oakley: Anything you know we're so hung up.
Bryan Oakley: And we have to be right on on how much uncertainty, the images have to.
Bryan Oakley: To allow us to say whether the shorelines actually moved significantly or not, that.
Bryan Oakley: But at the same time you can't do a global analysis and download tiles have to test for every part of the planet, you really are relying on something like Google earth to do a global scale.
Bryan Oakley: study, so I I i'm not quite there on the satellite stuff I prefer aerial when possible, because of the higher resolution and the more constraints uncertainties, but.
Bryan Oakley: There are places where you just don't have that, so I think there's still a need for it, and I Mike I would welcome that kind of review, I think that Google or it's fine for that kind of analysis and I think having that.
Bryan Oakley: Development type barrier island kind of you know metric out there is probably pretty useful and it's been a while, since a really good barrier island inventory papers been out there, anyway, so.
Christopher Hein?he/him: That was my thought on it too is if this really updates this stuff I mean the updates the cookies work nicely I like.
Christopher Hein?he/him: I wonder if some of the differences there in the numbers that you're coming up with our debt are based on definitions that was the thing that you know you mentioned yourself my email barrier island versus.
Christopher Hein?he/him: drop the word island if I guess if you don't have water on all four sides, and that would make I would imagine that's going to shift the numbers quite a bit.
mfenster: yeah fortunately I think some of the some of the.
mfenster: Some of the problematic interpretations are usually pretty small and spatial scale, so I don't think.
mfenster: i'm not sure that it's going to affect the overall results, all that much least we're pretty confident with moving forward publishing the results, given that scaling resolution yeah.
mfenster: They have if there's you know relic barriers, there are marsh islands, you know it raises some very interesting questions about what is the barrier island.
mfenster: And certainly we were asked by the reviewers in the first round to come up with a better professional definition which surprised me but it's true.
mfenster: And so we're kind of deferring to a very general definition stand in front marsh behind.
mfenster: facing an ocean.
mfenster: Thanks a lot for your feedback you guys.
mfenster: try my camera one more time and hope it doesn't freeze.
mfenster: justin are you still out there.
Bryan Oakley: So we've got about five minutes i'll start the posters up guys.
Bryan Oakley: I will say great job so far.
Bryan Oakley: who stepped up if you're talking to me, yes I stepped away to fill my water bottle up real quick.
Christopher Hein?he/him: Thanks to the links is smart if you're here and listening.
Bryan Oakley: yeah I was just last.
Christopher Hein?he/him: Year planet that's the one elite a that's one of you guys have great access to be you right.
Alice Staro: Yes, yes, so we.
Alice Staro: We started a collaboration with them actually before the you got a quarter from from them, so be any way to you as a large availability of said, because there is the Center for remote sensing.
Alice Staro: planet is great because.
Alice Staro: I have no idea how much single image would cost, to be fair, I know because I did that research before having access planet, that if you want.
Alice Staro: it's called.
Alice Staro: For something there is another satellite was around one meter resolution and the cheapest image that they could find from different providers was like $800 for one image per click so next so it's a pretty small area okay it's not the size of our state.
Alice Staro: And so.
Alice Staro: planet is good because it's a good resolution, as we said 3.7 this this satellite goes over the same spot at least twice a day.
Alice Staro: So, if any chance that you had a cloud on your specific points you there's a good chance that you could get an image, the same day.
Alice Staro: With branded island entitled place it's harder because maybe you got it, but it during high tide, so if you're looking at the shows you don't see them and that's also one of the reason why I had the images in the second one for 2018 so late, compared to this terms of time frame.
Alice Staro: What you have to like make.
Alice Staro: Take the good that you can have from what you have and overall planet, so he works perfectly, it also has a limitation that is only has four bands, instead of no plans at eight.
Alice Staro: And so I know that they were planning to add an extra band that it's called coastal Ben and it's specifically done to map the sediment suspended in the water column in shallow water so landsat has it and it works great if you want to map sediment transport, for example in.
Alice Staro: delta so.
Alice Staro: But again, if you're said if you're showing 30 meter.
Alice Staro: lancer completely useless.
Alice Staro: But anyway, they were planning to add it i'm not sure what stage of this development, they have they are.
Alice Staro: But I also I also know that if you have a lot of water.
Alice Staro: You don't need to really add several spectral indices i'm speculating This is like a.
Alice Staro: ratio or balance, depending on how do you calculate it with different spectral bands, and so it highlights this spectrum response of a pixel so specific value and, for example, the ones that are indexes that highlights the soil responds to has visit vegetation and so on.
Alice Staro: But here the only one that you actually would need to add is the one that is calculated using the coastal then.
Alice Staro: The analysis that I did that are being discussed running this is it could be probably done without the one that I did I did anyway so.
Alice Staro: let's say that even if you have only four bands it's OK, because it's there is so much water and he I clipped out, if you remember, I had I was spoke.
Alice Staro: At the bottom of a mass, because actually kicked out the European areas, but for the work that you and Catherine do that could be an issue because.
Alice Staro: I was being sent in the middle of the night, and when I knew that there was the city, and so I decided to Okay, this is not the target of my work, I will just clip it away, but for you guys, that would be not possible because you're actually considering you been.
Alice Staro: spots um.
Alice Staro: So yeah planet it's okay for for my work and.
Alice Staro: It has limitations, though, as like i'm not sensing to me, is a tool, so I need to recognize that it has its limitation is uploaded.
Bryan Oakley: I gotta jump in guys to keep us on schedule I hate to do that when we're having great discussion, but our our posters are going to get started at 1020.
Bryan Oakley: But we do have time scheduled at the end of the poster session to have more discussion, and we can do that, that so i'm going to hopefully not mess this up, I don't see the chat so if anybody just unmute if something's going wrong, and let me know.
Bryan Oakley: What how this is going to work for each of the posters.
Bryan Oakley: Is you have a pre recorded presentation and then hopefully the speakers there to answer any questions for up to five minutes, or so we have a 10 minute total for each.
Bryan Oakley: Each presentation and i'm going to largely let the presenters here with their pre recorded remarks introduce themselves So here we go.
Bryan Oakley: Let me sorry i'm going to do this, one more time and just make sure i'm good i'm going to share my screen.
Bryan Oakley: and make sure i'm sharing sound all right here we go.
Bryan Oakley: Hello everyone and welcome to my talk on how down to earth communities respond to growing and do surgeon this work was completed at montclair State University.
Bryan Oakley: And, in collaboration with researchers at woods hole oceanographic institution Okay, what are grains well, if we look at the introduction section on the poster.
Bryan Oakley: grains are short perpendicular rock structures that slow along sure occurrence in order to trap sediments in order to stabilize beaches and widen them and protect each my properties.
Bryan Oakley: However, grains that trap sediments on one side, often lead to segment starvation on the downdraft coast of the growing resulting in down different Community responses that can range from.
Additional green construction beach nourishment or Community retreat if the Community doesn't have the financial means to do so.
Bryan Oakley: So the main question that this research, aims to tackle is how do communities downdraft of grains respond to this induced erosion.
And when will they respond to this erosion, so in order to address these questions we have built a couple to morphic economic model and then seen in the message methods section, the Left column, where we can have to neighboring communities in the plan view and panel a.
In an in an asymmetric wave climate such that along shirts that transported sediments can settle in the upstream Community Community equals, one on the left, as a result of the growing in their community.
And segments that bypass that growing or, therefore.
Reduce relative to the long short transport and sentiments that would occur naturally resulting in heightened erosion and the downdraft Community or sell equals to on the right.
And in cross sure in panel be we also account for short face dynamics such that short face deepening relative to the equilibrium profile results in.
sediment transport offshore toward the short face toe and the opposite would be true when the short face is milder in slope and the equilibrium profile.
Now the beach width is seen as an environmental amenity that's capitalized into the beach front property value.
and results in it protective and recreational benefit to the beach front property, as well as the England community.
And when coupled with the costs of growing construction or beach nourishment we can perform cost benefit analysis to determine which strategy is best for the Deaf community to take based on what maximizes their net benefits.
So in the model, what are these down to have Community responses look like, well, we can have in the middle column top left panel panel a.
can have neither growing construction or nourishment in penalty, we can have downdraft growing construction handle see downdraft nourishment for in penalty a combination of the two.
And then we can also have time delays in these downdraft responses, so we hypothesize that the main drivers of the downdraft response, are the levels of wealth and the Community.
or in the bottom regime diagram what we can see is on the y axis we're plotting the baseline property value.
In the downdraft community and then on the X axis is the Community size or the number of property rose England.
And, in general, moving from low wealth too high, well, so the bottom left corner, up to the top right corner.
We have no intervention, so no no griner nourishment delayed growing without nourishment initial Brian was nerve without nourishment.
Initial greeting delayed nourishment and if the Community has enough resources, then both grind and nourishment.
So, how does this compare to what we see in the field well what we noticed is that there's a relationship between population density and the time at which groans were constructed.
In panel a on the left, we have communities at the start of the 20th century with high population densities building their grains very early on.
and communities that had lower population densities decided to delay their current constructions as seen by the Green circles.
And if we look at the groin construction relative to the uplift growing or the delay in growing construction as a function of this population density.
In general, in both the field in the model we see a decreasing trend where high population densities result in very short.
Time delays and low population densities results in high time delays, so why is this important well for the future in the future conditions, what we can see is that if we look at increasing resource economic costs as a result of.
Reduced supply and increasing erosion rates as a result of increased sea level rise rates in general.
If we have low background erosion rates and high growth and costs, we would see mostly a shift toward nourishment and the opposite would be true if there's lowering costs and high erosion rates suggesting that the current.
management scheme of soft construction might be switched in the future, and we might see a shift toward hard structures, and this would result in full property abandonments so that's the the short end of it.
and feel free to swing by my poster if you and in chat if you have any further questions and we can go into a little more detail thanks so much.
Bryan Oakley: All right, I apologize blue that just a tiny bit I was supposed to leave you up so you were in the lower corner of the screen there, but you did such a nice job explaining your poster I don't think it really mattered you really did a nice job with that.
Bryan Oakley: Does anybody have any questions.
Bryan Oakley: I think this is really interesting work hard, because there is the idea of what's going to happen in the future, not just from the coastal.
Bryan Oakley: geology but what's the reaction, going to be in terms of what are people going to do to the shoreline on these eroding barrier shorelines because there's so much development on some of them.
Bryan Oakley: That, how are we going to handle that in the next 50 years I think there's just so much interest and value to the work you're doing.
Arye Janoff: Thank you.
Bryan Oakley: Anybody have any questions.
Bryan Oakley: i'll ask one or crying still allowed on some of these areas in current management practices or would it have to change.
Bryan Oakley: kind of the management strategy.
Arye Janoff: And grains are definitely so loud there's actually a lot recently passed in North Carolina they previously weren't allowing hard structures, but I think that they they are now considering hard structures along the coast.
Arye Janoff: In general, most communities are employing soft engineering at this point, each nourishment, for instance.
Arye Janoff: However, there are other projects in New York, where they rehabilitated grains in the rockaways or long beach region.
Arye Janoff: And, and that has served as a compliment to beach nourishment so Greens are still used not as pervasive as in the early 1900s when it was very community by Community based management schemes.
Arye Janoff: But there are also people who lobby for you know, the extension of terminal grants in order to travel to transport and sediments without any regard for downshift you know close to impact.
Bryan Oakley: Thank you, thank you.
Bryan Oakley: I see if I can make my screen share a little bit.
Bryan Oakley: Any other questions for you, before we.
Bryan Oakley: move on.
Justin Shawler: Sorry what's your personal take on the potential role of of grains and incredibly deadly jetties in terms of like a regional sentiment management approach, like the core in particular is moving towards.
Justin Shawler: You know borrowing sand from from an inlet right, for example, and placing that on an adjacent beach right if you keep all the sand within a system is there a role for for crimes in jetties, particularly if you're going to engage in.
Justin Shawler: Like back passing to move, you know, increasing rate so scraping sand from one part of the beach to the other or more bypassing with with pumps things like that is there, do you think there's actually a role in the future for these features, especially if you're taking a regional perspective.
Arye Janoff: yeah it's a good question.
Arye Janoff: I especially like the the what's my opinion on it.
Arye Janoff: So the role, I would say, of jetties in general.
Arye Janoff: And, and this is a very elementary analysis of it this isn't from like you know hydraulic or cultural engineering analysis but.
Arye Janoff: I think that, in general, jetties can be useful, because they can both serve to keep stand within a system that, at least on human time scales we're interested in keeping sanden.
Arye Janoff: To protect communities That being said, we know that not every community is capable of being protected, we might have to retreat in certain areas, so maybe.
Arye Janoff: It would just be exacerbating the issue or or keeping us in place longer than we really should be, and then you mentioned, you know beneficial you, you know use of materials jetties can also help to reduce.
Arye Janoff: You know any sand accumulation inlets which could be navigation hazards could potentially reduce the costs of dredging in the inlets but then they could also exacerbate those.
Arye Janoff: Those issues that's why I said it was a very elementary level, because sometimes there could be sediment accumulation and inlets that we didn't necessarily know what occur as a result of jetty emplacements, so I think that there's a role, but.
Arye Janoff: To the extent that we can we should be moving away from hard structures and we should be moving away from trying to fix you know.
Arye Janoff: Our shoreline in place, but that said it's obviously very difficult to get people to pick up and move it's difficult politically it's difficult, you know socio economically.
Arye Janoff: And oftentimes it depends on the community's resources, whether they can actually move or whether they decide that they want to stay in place so that's my open ended answer to your question.
Bryan Oakley: Thanks sorry.
Bryan Oakley: We got to cut it there to get to stand schedule, but again, you have a discussion period at the end, thank, thank you for both for that discussion, though our next speaker is is Catherine names and her co authors working at sandy hook see if I could do this right, this time.
Bryan Oakley: hold on hold on guys.
Bryan Oakley: I forgot to share my screen i'm sorry guys, thank you for firing in on the chat.
Bryan Oakley: Let me get that on I knew there's going to be one mess up at least today.
Bryan Oakley: Thankfully it's by me alright share screen and i'll start that over.
Bryan Oakley: I hadn't shared and then I turned it back off, so my apologies, Catherine will start over and i'll adjust the schedule, as we go.
Bryan Oakley: hi i'm going to talk today about my poster on downdraft migration of shoreline facets at sandy hook, and the effect of different drivers and implication for park management.
Bryan Oakley: So sandy hook is a part of gateway national recreation area or gate that occupies the northern portion of the barrier spit extending from the north New Jersey shore into New York harbor.
Bryan Oakley: At sandy hook three different shoreline facets, have been identified in the past, indicating a change in direction and sediment mobility.
Bryan Oakley: So that's shown on this figure adapted from Alan 1981 and the boundary between these facets, has been shifting through time in the direction of sediment transport so to the north, on the ocean side of sandy hook and i'm to the southwest around the tip of sandy hook.
shoreline position has been monitored, since 2003 with handheld GPS units and it's been monitored seasonally beginning in 2006 to capture both the summer and winter conditions of the beach.
This monitoring follows a consistently applied monitoring protocol, and it has resulted in a 17 year plus shoreline record.
The monitoring protocol identifies the shoreline position via the location of the neat high tides Washington and we use this data set to derive with a rate of boundary migration through time of each of the facets.
So this figure shows the result of the shoreline monitoring it record, it shows the identification of inflection points in the shoreline that sure the boundary of each facet.
So the initial identification of the inflection points was done using matlab code identifying different changes in slope to the shoreline and then through human review to make sure we were consistently identifying sort of the same shoreline feature through the entire shoreline record.
So using those different inflection points we can track how quickly those boundaries are moving through time, so the facet one facet to boundary had a migration rate of about 10.7 meters per year so from 2003 to 2019 the inflection point shifted about 244 meters to the north.
In general, the boundary shifts farther and northward than westward since that's the direction of sentiment transport.
But major storms and storminess displace a facet further Western North and don't follow that linear trend.
So you can see that in this lower graph where hurricane Irene and hurricane sandy have been outlined and read they don't fit that line of best fit the rest of the surveys are on.
and have much greater westward displacement associated with shoreline erosion.
The facet to and facet three boundary had a faster rate of displacement to the north, and this this facet boundary had the strongest linear association and a rate of migration of 38 meters per year so.
We also track the location of the tip of sandy hook since it's a spit extending northward.
The tip had a faster rate of movement westward than northward.
And that's because it's the chip actually extends into a federal navigation channel that stretch every one or two years.
So surveys after the dredging of the navigation channel have a slower rate of migration about 9.3 meters per year than the entire data set which had a rate of migration of 23 meters per year.
which makes sense as material is removed from the system, the tip cannot migrate North as quickly since are actively dredging to prevent that.
Yet longshore transport is the primary reason for these facets shifting but other drivers like storminess dredging and beach nourishment all affect the shoreline.
Something that we thought was interesting was erosion is associated with the upper portion of each facet so as that facet boundary shifts so does that area of erosion.
So you can kind of see, this is a DSS map of shoreline changed through time and these major areas of erosion are associated with those facet boundaries so within facet to.
The largest area version tends to be about 10 to 20 meters up drift of that boundary so it's shown by this graph where sort of pick the largest vector England displacement.
Katy Ames: Every year, and plotted the distance from the facet boundary to that area of erosion so it's important information for the park.
Katy Ames: Because, as these margins of these facets shift to the north, so does that sound better condition that's associated with each of the facet facets.
Katy Ames: So shifting facets and areas of erosion, are of concern, because they threaten different recreational activities and infrastructure.
Katy Ames: So if we can provide monitoring and information to them from our trial and monitoring protocols that's helpful for their decision making, as they're working to provide the best experience for visitors and for the natural component of the park.
Bryan Oakley: All right, thank you for that we had one comment so far Mike fenster just said very interesting approach, looking at the.
Bryan Oakley: inflection points and he asks if you find any trend in the seasonality or is that noise and what other sources of noise or uncertainty limit that trend analysis over your decade old timescale.
Katy Ames: hi I hope you can hear me okay great.
Katy Ames: I didn't have a chance to look specifically at the seasonality, you can kind of see in the graph just the green and red is spring vs fall, so you can see some of the fall shorelines I don't think fit that sort of line of best fit as well.
Katy Ames: But i'd be really interested, specifically in like how stormy a season is and how that affects the different displacement rates.
Katy Ames: something to look into in the future, and then, as far as uncertainty, I mean we have with that monitoring protocol, we have a lot of different sources of uncertainty from you know the person monitoring the slash line to specific specific water level that was occurring during that's Washington.
Katy Ames: So with our like these SAAs analysis and metrics we have kind of a built in for ocean side, plus or minus 10 years.
Katy Ames: You know so over decades scales, you can kind of trust anything that's above that 10 meters, but with those lines of best fits and all those R squared values uncertainty is definitely something to consider with any any of this type of trolling and Alice this.
Bryan Oakley: Thank you Mike Mike just asked if there's any way to see that part I zoom back out to the whole poster but oh it's a great reminder to everybody that the posters are all available on to go in and look at them as well after after the session.
Bryan Oakley: Any other questions for for katie.
Bryan Oakley: So well designed poster I spent some time looking at it yesterday thanks.
Bryan Oakley: Going once going twice for questions.
Bryan Oakley: rose put the link to the session in the poster in the chat Thank you rose.
Bryan Oakley: All right, i'm gonna keep my screen up and not mess anything up here, hopefully and move on to our next presentation.
Bryan Oakley: Which is rose rose Palermo.
hi everyone, my name is rose Palermo and i'm going to talk to you today about barrier islands stability and characteristics segmentation link skills explored through the competition between overwatch and a launch for segment transport.
And the motivation panel i'm showing you several barrier islands found in low title range environment.
you'll notice that these barrier islands have pretty different shapes that some of them are really short and really curvy and some of them are pretty long and really straight.
And i'm trying to explore using a new framework why that might be so the question i'm asking is can we.
conceptualize barrier island stability in the context of low tides using overwatch and waves, which strongly influenced barrier transgression in these regions and can we predict stable along to our link skills of barrier islands.
So the two processes that are important in this environment or in the system are overwatch and a lot more segment transport.
overwatch is an onshore effective sediment fox that X to upgrade the barrier and allows it to transgress by filling in the back barrier.
And along to our settlement transport here we're thinking of as a diffuse of sediment flux that smooths curvature perturbations along the coastline, so you might think of overwatch as introducing perturbations and along sharp settlement transport as diffusing them in this, in this context.
The way I am conceptualizing this barrier stability analysis is using the Pec line number which.
If you're not familiar is a number a ratio that compares the rate of an effective process to a rate of a diffuse of process and this allows you to evaluate stability in fluid flows and so we're treating this here as a more for dynamic percolate number so.
What that means for this system is the diffuse of time scale TD, is a longshore.
Like scale, so the leg scale the long short curvature squared divided by the diffuse liberty, which is the function of the depth and the short face.
the height of the wave period of the wave and the angle, at which the wave approaches the coastline.
that are effective time scale is our characteristic length skill for infection, which is the width of the barrier divided by a characteristic.
speed of overwatch, which is the shoreline change rate for overwatch which can also be thought of as the overwatch books divided by the height of the barrier, plus the depth of the back barrier.
Bryan Oakley: So for our particular number we plug these two things in and get that in the bottom left and so we're trying to use this checklist number to understand something about think skills and stability.
Bryan Oakley: So if the number is equal to one the effective processes equal to the diffuse of process or the rate of these two are equal, then.
Bryan Oakley: We can solve for the long short length scale and that's shown here what that means is if we have perturbations introduced by overwatch events at a scale.
Bryan Oakley: Less than the critical along Charlene scale then diffusion will be able to smooth them if it is equal to it, then these two might be balanced and these perturbations may be able to persist.
Bryan Oakley: And finally, if it's greater than it than it may be affection dominated and the barrier we preach we explore this in the Gulf of Mexico to start.
Bryan Oakley: i'm showing him the top two panels along shoreline skills, when the number is equal to one for a range of overwatch flexes and if you 70s and for a range of fact barrier depths and a few cities.
Bryan Oakley: And the Gray boxes over lying these two figures show the range estimated for barriers and the Gulf of Mexico, and if we select just.
Bryan Oakley: One subset of this range, then we can find in a long short link skill, when the tech line number is equal to one of eight and that represents about a third of barriers in the Gulf of Mexico, a third of the size of barriers and Gulf of Mexico.
Ilya V. Buynevich: And what that means is that the average barrier in the Gulf of Mexico likely has a number of greater than one.
Ilya V. Buynevich: But these, but a third of the barriers they have the number of less than or equal to one, and these are these.
Ilya V. Buynevich: very short very curvy and highly dynamic barrier islands, and so, but my future work will further quantifying each of these barriers individually and try to explore this number a little bit more.
Ilya V. Buynevich: conclusions and future work.
Bryan Oakley: For barriers and low title rich environments, we conceptualize evolution as a comparison of overwatch and a launcher sentiment transport yielding a barrier island perfectly number.
Bryan Oakley: When this barrier island brooklyn number is equal to one.
Bryan Oakley: Like skills calculated are comparable with unstable quickly transgressing and high curvature barrier island and future work will test more field examples and further develop alternative dimensional ratios.
Bryan Oakley: i'd be happy to take questions now or by email, which is at the top of the poster Thank you very much.
Bryan Oakley: Thanks, for us, we have time for questions so.
Bryan Oakley: i'll us up Mike fencer has one, is there any way to determine which dp 70 or infection variables are more important than others and driving the stability and instability.
Rose Palermo (she/her): Well, thanks for the great question.
Rose Palermo (she/her): I think that, because there's a square root term in there.
Rose Palermo (she/her): There might be a simple way to test that just by by varying it with a stability analysis and I haven't done that yet, but that would be a great thing for me to do, but some of these terms have a much wider range than others, also in the field.
Rose Palermo (she/her): So that might be.
Rose Palermo (she/her): Another thing to constrain it to.
Bryan Oakley: I agree with Mike That would be a cool test to do.
Bryan Oakley: Any other questions for rose we got a couple minutes.
Rose Palermo (she/her): i'll just say I use the Gulf of Mexico examples, but not the tree could be a good place to explore this I was thinking, while you are giving a presentation Bryan.
Bryan Oakley: rose i'm happy to talk about that anytime you just reach out and we could find some time and talk about an amateur i'll even take out in the field one, so we can we can do that again.
Rose Palermo (she/her): Not that.
Ilya V. Buynevich: quick question two rows it's like a perennial one.
Ilya V. Buynevich: Can you input, the nano roadable sediments for the beach face so let's say it's stable and now there is pete and trees so you're rolling into that barrier, as the Allen keeps moving rather than into sand, is there a way to decouple it completely.
Rose Palermo (she/her): yeah so that's a good question so basically what.
Rose Palermo (she/her): The assumption, then there would be that the overwatch flux would go way down.
Rose Palermo (she/her): So you would just put the overwatch box as a control, rather than as a free variable so.
Rose Palermo (she/her): So yeah if we if we knew.
Rose Palermo (she/her): If we knew.
Rose Palermo (she/her): A priority the evolution of the barrier and you're trying to understand just.
Rose Palermo (she/her): This balance, a little bit more than, then we could do that no.
Ilya V. Buynevich: that's a tough issue, but it seems the more stable, it is the more chance that once it moves, you know going to expose the you know mods and and.
Ilya V. Buynevich: And trees, you know something other than sand sort of like in the Virginia southern Virginia islands and it's tough to build into models by, though.
Bryan Oakley: I mean Mike asked basically how, how will you validate the model what's your plan to do that.
Rose Palermo (she/her): um yeah so I what I guess, one thing I should point out here is that i'm not.
Rose Palermo (she/her): This number kind of evaluate the barrier island at one snapshot in time it's not an evolving model.
Rose Palermo (she/her): We can use evolving models to explore this a little bit more, and something i'm going to do in the future, but this really says for some amount of time, we know that this is the length of the barriers are with the barrier and the sediments boxes and 5070.
Rose Palermo (she/her): So how might that evolve in the in the near term or what are the processes that are that are affecting it most strongly in the near term so.
Rose Palermo (she/her): yeah so for some model validation I think that, looking at short term evolution might be.
Rose Palermo (she/her): A way to predict if it if it is a reasonable assumption.
Rose Palermo (she/her): And for more longer term stuff I would really have to look just that that's more sandy barriers, because the problem with.
Rose Palermo (she/her): For for this framework is that for money barriers both it's harder to a road and the settlement doesn't get free works in the system you're not getting over Washington.
Rose Palermo (she/her): deposition of that much so.
Rose Palermo (she/her): yeah I hope that answers the question and i'd be happy to talk more about it.
Bryan Oakley: All right, thanks rose, and thank you for the great questions guys.
Bryan Oakley: Are we're going to move on to our next poster.
Bryan Oakley: This is.
Bryan Oakley: Greg rodman and he's going to be talking about gadgetry point as well.
Bryan Oakley: take it away.
hello, my name is Greg reitman I am a recent graduate from eastern Connecticut State University.
And this project completed by Dr Brian oakley and myself is regarding century scale bathroom metric analysis for little narragansett bay and the aperture point conservation area on and around an aperture barrier and watch over island from.
The aperture barrier is a 2.4 kilometers long barrier spit which lives just south of little narragansett Bay at the mouth of the pockets of river estuary.
Before getting into the study itself, I would like to note figure, one which identifies significant tropical and extra tropical storms, based on water level.
The napa trade barrier used to have an approximate l shape to it, prior to 1938 as sandy point was still connected just north of the West most section of the present day barrier.
However, in 1938 the great New England hurricane made landfall in September of that year as a category three storm the storm severed sandy point from the rest of the barrier which started its migration northward into little narragansett bay.
figure to gives a picture of the study area to show the location of sandy point relative to its approximate 1883 extent when it was attached to the barrier.
To begin this study in 1883 high traffic survey, she was do reference to the study area, so the depth soundings maybe digitize those points.
A portion of the survey she used for the study is shown in Figure three to show the density of the measurements surrounding the barrier.
Bryan Oakley: Once all of the measurements were digitized the values were converted to metric and then adjusted for sea level rise relative to 2018 and then all measurements were then made relative to me and lower the water.
A zero line relative to me lower the water was established to outline the 1883 extent of the barrier as know measurements on the barrier above me and lower low water were available for this study.
Using the natural neighbors algorithm within as rock map a raster surface was created to interpolate the subsurface topography, which can be seen in figure for.
2018 lidar data were obtained for the study area and us along with the created 1882 raster to calculate deposition and erosion in the subsurface using the surface volume tool within our map.
The 1883 erosion and deposition values or subtracted from the 2018 values to calculate the mathematic change using the raster calculator tool and our crap.
Figures five and six show cross sections take it from the shore face of the barrier to highlight the transgressive movement of the barrier in the hundred and 35 year time span.
two locations of these cross sections in the study are shown on the shore face of figure seven.
Some things to know in these figures, is that there is not any significant change plus or minus one meter beyond approximately 250 meters from the barrier.
Also, the slope leading up to me and lower the water on the barrier has remained relatively constant while having retreated One barrier with landward which is approximately 100 meters.
figure seven shows the results of this study indicated were in the study area, there was a significant erosion or deposition plus or minus one meter.
Some things to know in this figure area surrounding the present day, extended the barrier, where the shore face is showing significant erosion for the barrier was in 1883 and significant deposition from its transgressive movement to its current extent on the North side of the 1883 barrier.
There was also significant deposition in a north, south orientation to the east of the 1883 extent of sandy point from overwatch and from sandy point in self having migrated northwards.
And I expected find from this study was the delta like deposition of features seen at the mouth of the pockets of river in the east of little narragansett bay.
This was unexpected because the River was previously thought to be sediment starved However, the source of the sentiment is unknown.
and table one shows the net loss or gain in volume for each identified section of the study area note that the shore face is the only section that experienced the net loss and sediment due to the transgressive movement of the barrier.
The Bay head delta is also identified here and is a subsection of the little narragansett Bay section so it's 700,000 cubic meters of deposition are incorporated into the little narragansett Bay values.
Alright, thanks for that Greg does anybody have any questions.
Bryan Oakley: Anybody have any questions for Greg.
Bryan Oakley: Oh Mike asked why we use one meter Greg.
Bryan Oakley: Greg are you there.
Bryan Oakley: So i'm not sure if greg's having technical issues or not.
Bryan Oakley: But we use one meter because of the uncertainty, the lidar and we add an assumed uncertainty on the barometric data digitizing as well Mike.
Bryan Oakley: it's probably very conservative of an error.
Bryan Oakley: Oh, you can't hear me.
Bryan Oakley: sorry about that any questions for Greg I was trying to get fancy and learn and join in two spots, so I could keep the chat going on my phone, but I guess that didn't work.
Bryan Oakley: Greg Mike asked why we use plus or minus one meter for uncertainty.
Rose Palermo (she/her): Sorry, we still can't hear you, I can see you're trying.
Bryan Oakley: To.
Bryan Oakley: Oh, you can't hear.
Bryan Oakley: You can't hear Craig.
Bryan Oakley: Can you guys hear me okay.
Rose Palermo (she/her): yeah I can hear you.
Bryan Oakley: Alright, so Craig I mean I can jump in for that, I mean Greg Greg did all the work on this, but basically one meter was are assumed uncertainty between the holographic chart from 1883.
Bryan Oakley: The lidar and kind of making both of those into the same space some very conservative estimate on uncertainty, I think.
Bryan Oakley: Any other questions.
Bryan Oakley: Yes, and if we can change.
Bryan Oakley: Any other questions.
Justin Shawler: Sure, Brian i've got a question.
Bryan Oakley: Sure fire away.
Justin Shawler: yeah do you think that the bay had delta like feature.
Justin Shawler: is something that could be mind for our drivers to basically for sands locally.
Justin Shawler: Is there even a need for that sand.
Bryan Oakley: Greg I don't know if you're there or not, but i'll i'll jump in basically.
Bryan Oakley: I don't think so My suspicion yeah now, we came Greg do you think we.
Bryan Oakley: Should we know anything about that that they had like delta or where are we at with our understanding of that right now, what do you think.
Greg Rodman: I think we saw that it was only.
A very deep addition to the system.
Bryan Oakley: yeah I mean it's not very thick justin and my suspicion is that that's probably pretty fine grain material knowing a little bit about the sea floor there.
Bryan Oakley: and probably not a great source of sand, it was just interesting that it even shows up at all, it may just be you know at the confluence of the of the.
Bryan Oakley: Title currents and the little narragansett Bay part of the the estuary there My suspicion that's pretty money.
Bryan Oakley: They do dredge the north part of sandy point that red area on the far north part of that that image and put that on the southern into sandy point every few years to maintain the navigation channel.
Justin Shawler: Great thanks.
Bryan Oakley: I can point you to another paper later if you want offline that we did on a different part of the south shore and inside of a break water that's even more exposed than that one, and it was a pretty silty sand, so it really wasn't a great replenishment targets.
Justin Shawler: Sure that'd be great thanks.
Bryan Oakley: Any other questions for Greg.
Bryan Oakley: i'll just throw a plug out there, that I am always amazed at the amount of detail those historic Hydra graphic surveys having them.
Bryan Oakley: Considering was 1883 when they did all that work.
Bryan Oakley: Definitely, I think it came out to 6000 points that I ended up digitizing yeah.
Bryan Oakley: that's also a testament to greg's patience to sit there and digitize 6000 points.
Bryan Oakley: All right.
Bryan Oakley: thanks for that Greg and the posters up there for anybody wants to go take another look at it and you can reach out to Greg or myself with any questions thanks Greg good job.
Bryan Oakley: All right, we're gonna move on to our next paper which is going to focus also on on estuary but a little further inside here at the plum island estuary, and this is a oh and ryerson and his co authors from Boston university.
Bryan Oakley: doesn't seem to be loading so give me a second to try to reload this one.
Bryan Oakley: There we go i'm going to be presenting on the bottom green size distribution through the plum island sound estuary in Massachusetts.
Bryan Oakley: And how this distribution impacts suspended sediment forgiven shear stresses under Title and storm conditions.
Bryan Oakley: The resiliency of New England salt marshes is being questioned duty accelerating sea level rise and limited fine grain sentiment availability.
Bryan Oakley: The plum island sound saltmarsh builds vertically through the production of below ground biomass and the deposition of suspended sediment.
Bryan Oakley: In this study we document grain size distribution throughout the plum island sound by analyzing 373 samples.
Bryan Oakley: 148 of the samples were collected and channel followings and the remaining 225 samples were obtained from the balls 1969 thesis we identified five major sedentary environments, consisting of the main sta channel, large and small title creaks point bars in the title Delta.
median grain size distribution sorting in schemas were determined from each of the sample sites.
You selected 32 representatives sites from the total sites.
And for each of these sites, we determine to the critical bed shear stress from ability, based on the local media in grain diameter.
We then use the hydrodynamic model to identify title and wave I do wave induced bed shear stress for comparison with critical stress.
With the hydrodynamic model three storm conditions were simulated the strong conditions were evaluated at both high and low inundation of the March platform and we found that storm waves approaching from the east.
During high marsh inundation produce the maximum shear stress and led to combine shear stress that exceeded critical shear stress 30 of the 32 representatives sites.
We also looked at where particles are transported as spend it sediment versus bed load, we found that under normal spring title conditions only nine of the 32 sites experience shear stress strong enough to initiate grain motion.
Generally, those sites contain the smallest meeting grain sizes across the all representative samples, regardless of the seven environment.
At these nine sites settlement travels an average of just a few hundred meters and suspension, the maximum distance of 855 meters.
And the location of the sample seems to have little effect on its suspended transport distance are finding findings show.
Based on the determined sediment transport distances environments fronting the Marsh can supply sediment for marsh deposition when the marshes inundated.
And that finer sands are more mobile and can travel further during high energy events, up to one to two kilometers additionally.
waves enhanced sediment transport and the marshes inundated and these conditions likely contribute more sediment to the Marsh than flooding tides do note that increased shear stress shown on the figure be on the right side of the poster compared to figure see.
Will wave orbital velocity is maintain uniformly high across the Marsh platform during storms, the bench here declines rapidly moving into the estuary from the flood title Delta.
This story storm and do sediment deposition may explain the homogeneous nature of the March 30 griffey do the increased shear stress from storm conditions being able to suspend a wider range of grain sizes compared to normal title conditions.
Bryan Oakley: Right, thank you for that oh and do we have questions for Owen.
Bryan Oakley: Any questions.
Christopher Hein?he/him: i've got a quick one for you um How does this compare with the thoughts that most of the sediment here that's making onto the Marches is not local, but a lot of it's coming from.
Christopher Hein?he/him: Offshore you know, through the during storms, how to it seems like this is a lot of moving around throughout the back barrier.
Christopher Hein?he/him: i'm thinking about.
Christopher Hein?he/him: chuck Hopkins paper on that do you know term talking about.
Owen Ryerson (he/him): No, I don't know that paper that you're.
Owen Ryerson (he/him): Specifically, talking about, but we did see that the greatest sheer stresses under strong conditions are by the the title outlet or inlet.
Owen Ryerson (he/him): In that most of the sediment transport we're seeing is happening in the in the main estuary as opposed to this smaller title creeks and channels.
Owen Ryerson (he/him): Does that kind of answer that question.
Christopher Hein?he/him: yeah I want to go to spend more time with the poster after and pull up both sex advice.
Christopher Hein?he/him: Models together and check it out to thanks.
Owen Ryerson (he/him): But an audit just adding to that anecdotally we kind of have seen that in the catalog creek suspended sentiment concentrations are really low suggesting that a lot of that sediment contribution is not from from the rivers that are flowing in March.
Bryan Oakley: Right any other questions for oh and.
Bryan Oakley: I don't know I just said it's a very well done poster I was looking at the last night so it's very well laid out.
Owen Ryerson (he/him): Thank you.
Bryan Oakley: Okay well we're gonna wait a couple minutes to get started on the next posts or just so we can stay on time for everybody.
Justin Shawler: hey Oh, and one other question here, going to the point about.
Justin Shawler: sort of bed sheer declining over the Marsh platform itself what would implications, do you think that has for.
Justin Shawler: sort of the long term resilience of these marshes are they almost dependent on erosion at the edge to to sort of feed the inland department relatively deposition on the Marsh platform itself or is that not a good takeaway.
Owen Ryerson (he/him): that's a really good question, I think that that's something that we're still trying to figure out is.
Owen Ryerson (he/him): How this is going to affect marsh.
Owen Ryerson (he/him): Sustainability moving forward and especially with that yet edge erosion how this bed shear stresses.
Owen Ryerson (he/him): are eroding channel edges and if channel edge erosion is depositing a significant amount of sediment on the march platform and kind of eating away at the at the Marsh from the edges and depositing that sediment on the.
Owen Ryerson (he/him): platform or or if most of that sentiment, as Chris Hein alluded to, is coming from a more C word source.
Owen Ryerson (he/him): But it definitely has the thought that are what we're what we're thinking here that.
Owen Ryerson (he/him): Storm conditions are the main.
Owen Ryerson (he/him): Transport of sediment on to the march platform in that title conditions are are not sufficient to.
Owen Ryerson (he/him): are likely not sufficient to sustain the Marsh platform.
Owen Ryerson (he/him): is one of the one of our main takeaways.
Bryan Oakley: All right, thank you for that one i'll get the next one queued up we've got about a minute or so until we get started.
Bryan Oakley: I will say thank you to everybody for hanging in there, our participant numbers i've been kind of tracking them every half hour or so have been really steady, as people have stayed engaged for this, so thank you for that alright our next speaker.
Bryan Oakley: I will let him introduce himself, he said he's only got a couple minutes of audio because the file limit size so sure you can chime in her some more after but he's going to take us well outside of the northeastern United States.
Bryan Oakley: to Estonia and Lithuania.
Bryan Oakley: Hello here i'm presenting a review of our coastal geological data set from Lithuania, as well as new data from Estonia, focusing on.
Bryan Oakley: heavy metal anomalies specifically magnetite interest concentrations in beach and doing sequences along the Baltic Sea coast and the use of low field magnetic susceptibility as a means of rapidly and effectively.
quantifying these natural occurrences.
So here the study sites include the islands of a stone, if not familiar if you can look at the video panel we're going to look at Dell enough Hema.
Just to the south of the largest island in Estonia sorry ma and then we're going to finish off on the caronia spit 100 kilometer long barrier spit divided equally between Lithuanian the North and Russian Federation and the South.
So the human side is very coarse rich in fact the relative magnetic susceptibility values are in an order of 10 to 20 and sometimes going in a negative, so these that magnetic cords dominated sense, in contrast, just to the south South rim assembles.
And here, you can see them in orange.
rectangles have much higher orders of magnitude higher magnetic susceptibility values suggest in background and anomaly concentrations of magnetite that are much higher.
Sometimes exceeding to the 3000 side and again there's similar to modern concentrations on the beach related to wave activity or in the demons are related to strong wind activity.
And you can look through the sequences so look at sediment cores and you can see that both upward through the dunes probably related to increase in the wind speed, as they do create.
As well as through the four ridges and Sarah ma you can see, over the past 400 years and increase in background, as well as anomalous content of have a minerals, as reflected by high magnetic stability values.
And it's important to notice that a lot of these anomalies also produce strong reflections and ground penetrating radar records.
Finally, finished off sort of overview of what's been going on along the caronia in spades So you can see from from the Russian Federation side and then transport along the shore all the way to Lithuania, you can see a decrease in small.
dark blue symbols decrease in magnetic susceptibility as as you get more and more courts dominated sequences however there's still.
quite a bit of variability and the numbers are similar to those and sorry ma in order of 10s to hundreds.
In si values, so we can use these magnetic susceptibility measurements as a proxy for high energy, then the variety of scale so as a proxy for hydro meteorological conditions going back into the past, thank you.
Bryan Oakley: Alright, thanks for the i'm gonna zoom back out to the poster scale and anybody have any questions for hill yeah.
Bryan Oakley: i'll ask Wendy how much of that is is processed driven and how much of that is source of sediment driven the variability in the magnetic susceptibility.
Ilya V. Buynevich: yeah good question, so the the overall picture is definitely source driven so it's a very drastic change.
Ilya V. Buynevich: Like even in Estonia between the two nearby islands so actually divided post or like the left side is a little light background, just to separate those two sides.
Ilya V. Buynevich: But once once you got sort of your pool of minerals, then its energy driven and he's going to be moderate storms, just like you saw in Rhode island and we're signing.
Ilya V. Buynevich: posters on the Great Lakes and to moderate storm, so you don't erode everything, resulting in.
Ilya V. Buynevich: A basically a discount for me, but he just went away the the lighter minerals so it's one of these interesting ways to get a ton of moderate storms.
Ilya V. Buynevich: And then there's duration versus magnitude right so thickness versus the degree of concentrations of these minerals, so you can really constrained both the waves and the wind near surface when speed.
Ilya V. Buynevich: Because it takes only a certain range of energy to leave behind magnetites of a certain size and.
Ilya V. Buynevich: density and then move all the light minerals away so magnetic susceptibility just a good way to assess very rapidly sort of the grain size and the content of magnitude without him counting for hours and days.
Each.
Bryan Oakley: Thank you Mike wants to know if there's any thoughts on using other heavy minerals, besides magnetic ones, particularly if you're interested in provenance up he just answered you just answered it indirectly so.
Ilya V. Buynevich: yeah I mean there are other if there's no magnetite than any other garnet study pair of magnetic but they'll always be higher than courts, which is slightly negative or carbonates.
Ilya V. Buynevich: So even if you just have garnet they'll definitely be got it just magnetite is the is the biggest contribution there but yes.
Bryan Oakley: He wants to know if you're interested in Provence.
Ilya V. Buynevich: Sure, just to explain this big contrast to me, this is the biggest one i've ever seen again i'm sort of a Jason, is there not that far away.
Ilya V. Buynevich: And all of a sudden it's like dramatically different sort of background and you cannot explain it just by the quieter energy and one and the other one being hammered by storms, a strong winds, the background, based on pause glacial sediment sources drastically different.
Ilya V. Buynevich: But yeah probably I mean it came from from the north from Finland, the ugly situation and a lot of a bedrock is carbon it so your background is sort of clean and zero almost.
Ilya V. Buynevich: For anything you're adding is from one glacially derived sediments and you just keep sorting it, you know by winds and waves so it's a really good way of looking at sort of snapshots of.
Ilya V. Buynevich: hybrid meteorological conditions that's sort of a buzzword what they use in the Baltic Hydra meteorological conditions right that's when done waves and everything just try to decouple them it's sort of tough.
Alice Staro: Especially.
Ilya V. Buynevich: door or.
Alice Staro: How you use magnetic signature on unconsolidated sediment right.
Alice Staro: So you take account only.
Alice Staro: The mechanistic susceptibility but without taking into account the direction of the magnetic moment inside the grace, because if you have unconsolidated sediment they could switch right and change orientation.
Ilya V. Buynevich: Right right, this is low field so it's not that affected but yes we use the the sensor that just sort of measures in all directions.
Ilya V. Buynevich: And measures like two to three millimeters into the sequence, but if we did course trenches too much greater detail, we can use the oriented.
Ilya V. Buynevich: sensor, which is much more sensitive, you can actually account for that, so you can actually align it in court or in trenches you can actually align it to you measuring along the layer
Ilya V. Buynevich: versus across the layer in some cases were actually measured sub samples from from corps so there's still sort of together but uh you know, then yes, the orientation would.
Ilya V. Buynevich: would be important, but the variations are so dramatic that you know those small variations do the orientation of elongated magnetites are not as issue i'm just presenting it to everybody has really quick.
Ilya V. Buynevich: and easy way to get a sort of relative magnetic susceptibility even after superstorm sandy you can measure you can measure the sort of the sentiment couplets here in New Jersey or elsewhere, and you can get a really good idea of the relative.
Ilya V. Buynevich: let's say strength of the storm surge and you can adjust your grain size.
Ilya V. Buynevich: Using magnetic susceptibility because small magnetites will hydrodynamic they actually course, other than some of the courts.
Ilya V. Buynevich: So you made up, you may end up with some of these upside down sequences that first don't make any sense i'm sure Chris and others we got into that a while ago but uh.
Ilya V. Buynevich: yeah if you corrected for susceptibility then it sort of starts making sense again you start getting hundreds dynamically finding awkward sequences so all of these things have to take into account.
Bryan Oakley: So alien Chris asked a question and we don't have a ton of time, but i'll ask a quick it looks like, at least at one of your sites you're seeing potentially a climate or human influence on the record any thoughts on the time scale or rsl ages, or anything like that.
Ilya V. Buynevich: yeah it's what we're seeing is for religious about 400 years so it's you know late 1600s early 1700s and remember that humans are affecting landscape there too much greater degree than, say on the east coast of the United States right so.
Ilya V. Buynevich: So i'm not sure we can tease out that that part within the within the.
Ilya V. Buynevich: effect on the local climate, but there is definitely getting either more energetic I would just keep reworking the same sand pile and we're getting a little more.
Ilya V. Buynevich: A little more heavy minerals, so you have to look through time, as well as vertically through space to compare apples to apples here the question.
Bryan Oakley: Excellent.
Bryan Oakley: Alright, we are gonna.
Bryan Oakley: move on to our next speaker.
Bryan Oakley: Which is going to look at it's a.
Bryan Oakley: charged with Carol falvey and we're going to look at effects on title restriction in a salt marsh ecosystem at the lyman reserve.
Bryan Oakley: My apologies.
Welcome to the poster presentation on the impact of Title restrictions on a salt marsh ecosystem and environmental monitoring project on the line and reserve.
i'm Kara falvey, and this is an ongoing undergraduate capstone project that is being completed under the guidance of professors happening and hubbard at the Massachusetts maritime academy and buzzards Bay Massachusetts.
Bryan Oakley: This is part of a long term study of Cape cod salt marshes which are ecologically important to our coastal systems as blue carbon buffers which protect our land.
Bryan Oakley: purifier water and provide essential habitat to a wide range of organisms are study was conducted at the lyman reserve salt marsh located in Wareham Massachusetts at the mouth of redbook stream.
Bryan Oakley: Read brooke is significant, as it is home to one of the last remaining native see run brook trout fisheries and Eastern United States.
Bryan Oakley: restriction in the marshes located at the intersection of the born, where him Plymouth town lines and crosses red brick road, it is classified by the United States geological survey as wh 40 which is restricted and wh 41 which is unrestricted.
Data Collection for our study that is reported on this poster begin in September 2020 and concluded in November of 2020.
We monitored water levels on each side of the restriction using hobo data loggers program to record measurements every 15 minutes.
We conducted analysis of nitrates and phosphates and surface waters on each side of the restrictions with a hatch Dr 1900 portable spectral photo meter on a weekly basis dissolved oxygen and solidity levels on the Marsh were monitored weekly with a y si pro 2013.
As you can see from our data analysis site wh 40 and wh 41 had similar sensor depths site wh 40 which is restricted had the lowest value of 0.093 meters and the highest value was 1.897 meters.
on site who 41 which is unrestricted the lowest value was 0.044 meters and the highest value was 1.898 meters.
regards to conductivity site wh 40 which is restricted conductivity levels in the water range from 0.7329 milliseconds per centimeter to 32.3189 Melissa Siemens per centimeter.
At site wh 41, which is the unrestricted site conductivity levels range from 0.7236 milla Siemens per centimeter to 31.8669 milliseconds per centimeter.
We converted these levels to practical salinity and found that the slowly range from zero parts per thousand to 22 parts per thousand at site wh 40 and its site wh 41 facility range from zero parts per thousand to 21.8 parts per thousand.
Our average nitrate levels over the fall 2020 semester or 0.9 parts per million and the average phosphate levels were 0.62 parts per million.
At site wh 40 which is restricted.
And at site wh 41 which is unrestricted we found average nitrate levels were 1.17 part per million and average phosphate levels were 0.98 parts per million.
We characterize hypoxia below three milligrams per liter, as you can see from our data know hypoxic events were noted during our collection.
The range at St w H 40 which is restricted was 7.65 to 11 point 11 milligrams per liter and at site wh 41 unrestricted the range was 6.77 to 11.6 milligrams per liter.
From the collect data collected, thus far, we concluded that the Marsh system and the linemen reserve range from mainly fresh water to brackish water with a diurnal title pattern.
There was not a significant difference in the water level from one side of the restriction to the other indicating that the restriction was not impacting water flow in this area of the Marsh.
We did note that nitrogen and phosphorus levels appear to be elevated in the Marsh fun yo hypoxic events were observed during our election.
Bryan Oakley: Well, the studies did not find that the restriction in this area of the Marsh was impacting title flushing there are additional questions regarding the March that would warrant further study.
Bryan Oakley: Our plan for spring 2021 is to conduct a more thorough vegetative analysis on the site, including obtaining imagery from a drone camera Finally, we will be conducting nitrate and phosphate testing on pure water, so that our data is more consistent with existing.
Bryan Oakley: Right, thank you for that CARA.
Bryan Oakley: Do we have any questions.
For CARA.
Justin Shawler: CARA.
Justin Shawler: So it looked like from the the math and the poster that the the watershed for the creek has to be pretty small but can you speak to upland contributions that might be influencing any of these measurements, or is it purely totally driven based on what you've seen.
Kara Falvey: From what I seen it seems to be totally driven I think we are from kind of the the end of the Marsh.
Kara Falvey: You know, to where this restriction is is is not too far, but we do think that elevation and the Marsh is actually contributing, because we are seeing mostly kind of fresh water.
Kara Falvey: or brackish water we're not seeing a you know, a huge influx of salinity there, so we think that's the elevation at the Marches kind of contributing to to those salinity levels, but we don't know the exact distance from where the restriction is to the the edge of the mark.
Kara Falvey: I hope that answers the question.
Justin Shawler: yeah it does, thank you.
Bryan Oakley: Carl i'll ask one real quick how big is the restriction, I might have missed that I mean is, it is it all.
Bryan Oakley: 18 inch covert or is it a you know, an eight foot tunnel underneath the road.
Kara Falvey: No, it is a pretty small restriction, it is just a covert.
Kara Falvey: Where bridge kind of passes over.
Bryan Oakley: Thank you and rose has a question.
Bryan Oakley: This challenge so i'll ask this i'm happy to know the answer this went to what might be the effect of the increase nitrogen and phosphorus on the ecology of the system on either side of the restriction.
Kara Falvey: yeah that's a really interesting question that's actually you know, I would like to do further study on.
Kara Falvey: You know if we're we see a large frag my US population on either side of the restriction for me i'm really interested on you know what impact is this kind of nitrogen loading doing on.
Kara Falvey: kind of plant bio mass you know, a creek stability and things like that you know, unfortunately with you know our study.
Kara Falvey: As I continue kind of researching and doing a literature review on it, I want to look more at kind of pour water than surface waters, because i'm not quite sure that's going to give me.
Kara Falvey: You know any information how it's really you know, affecting that plant biomass, but that would That is something that.
Kara Falvey: You know, has been a concern of you know how is it impacting you know either the sport Tina that that's there, how is it influencing the growth of the frag mighty population that's there so Those are some of the things that we're looking at.
Bryan Oakley: All right, thank you for that answer.
Bryan Oakley: Any other questions.
Bryan Oakley: Alright, I will cue up the next one will start in about a minute or so guys.
Bryan Oakley: Alright, our next presenter is Joe marsalis he with his co authors he's taking you back to napa tree you'll notice we spread the napa tree talks out a little bit so you guys didn't get an apple tree overload in the session to take it away joey.
Bryan Oakley: hi my name is joey march Lucy and i'm a 2020 Eastern Connecticut state university graduate with a degree in environmental or science concentrating and sustainable energy in a minor in astronomy outreach and public presentation.
Bryan Oakley: My research during 2019 2020 in the year science program was primarily focused on the coastal GEO morphology of the napa tree point lagoon and napa tree point watch hill Rhode island.
Bryan Oakley: Now poetry point conservation area has long been recognized as a vital ecologic refuge located in watch hill along the Rhode island coastline.
Bryan Oakley: Various migratory shorebirds species, along with fishing invertebrates, most notably the horseshoe crabs find habitat within this area in rely on the geo morphology of the napa tree point lagoon to provide a balance of shelter and regular oxygenated water supply.
Recently, there has been concerned pertaining to the lagoon inlet closing posing a potential threat to the system.
Greg rodman my former period Eastern Dr Brian oakley our research advisor and myself wanted to follow up on alley augustine's 2018 2019 napa tree research Allah was also a former period Eastern.
to determine if the lagoon and let is at risk of closing we identified four main objectives to focus our research on.
Number One was titled delta bed form observations observed during both eben flood tides across the title Delta.
Number two was English Channel current velocities measured from nine different stations across the title delta observed also during both ebb and flood tides number three was measurements of the symmetry of the lagoon taken in both January 2020 and April of 2018.
Number four was the inlet cross section, we wanted to measure this equal up this inlet cross section to compare to a brian's equilibrium constant.
Throughout the bed form survey mostly flood oriented dunes were observed along the title Delta, in both the ebb and flood tides.
This suggests there is greater sediment transport capabilities throughout the flood tide ripple orientation is more easily reverse during a title flip and still many ripples remain flood oriented throughout throughout the peptide.
Nine stations were arranged throughout the title delta for the current velocity measurements.
The sediment was identified to be mainly medium sand throughout the title delta, which has a minimum transport velocity by water of 20 centimeters per second we therefore determine that flow velocities blow this threshold were insufficient to transport significant amounts of sediment.
From these surveys, we were able to determine that there is more transport potential during the flood tides at all nine stations throughout the lagoon.
most notable current stations nine and eight located at the North East end of the lagoon and let reached 80 centimeters per second a flow velocity during the flood.
During the during the flood velocity surveys and only peaked at 75 centimeters per second and 40 centimeters per second respectively throughout the peptide.
army corps of engineers taco bathie lidar data of napa tree point lagoon from April 2018 was used as a baseline for the bath of metric comparison.
In January 2020 we completed an arty K GPS survey of the title Delta.
Both data sets were processed utilize utilizing Ezra Arc map spatial analysts tools and changing sediment thickness it was calculated over the 21 month period with.
Arc maps roster calculator through this substantial GEO morphic change was observed with the title Delta.
Over this time period, the only had filled into the south, and since migrated to the north, the shield also appeared to have grown significantly in size, as well as shifting north, along with the inlet.
The expert to the north, appears to have been cut through by the New England into the south has grown almost entirely blocking Evan flow at the south end for most of the title cycle.
Over this course of time overall net deposition of 440 cubic meters was observed and the January 2020 our tk GPS survey.
o'brien's relationship can be used to determine the expected inlet size of a lagoon based on the title prism to reach sediment transport equilibrium.
Augustine at all in 2019 determine that P of this system equals 29,000 cubic meters which calculates to an inlet size and equilibrium of five square meters this five square meters calculated was measured as the actual inlet area in 2019 by Augustine at all.
This same inlet was measured, to have an area of only 3.2 square meters, however, in our January 2020 survey suggesting the lagoon in like could close separating it from little narragansett bay.
All for studies suggest the system is flood dominant and net deposition all.
This could eventually result in the closing of the lagoon and let an isolation of the lagoon eventually resulting in negative ecological impacts to this unique ecosystem this site remains to bear additional monitoring in the future.
All right.
Bryan Oakley: All right, thank you joey anybody have any questions for Joe.
Bryan Oakley: rose so cool study was there any difference in the size of the dunes in the bed form survey joey.
Joey Marsalisi: Great question yeah there was some minor size differences in the in the dunes on the exact numbers I don't exactly remember, without going back and looking at the data.
Joey Marsalisi: off the top of my head, but for the most part they were fairly.
Joey Marsalisi: Equal sizes.
Bryan Oakley: I mean, these are all small dunes in a very small coastal system.
Bryan Oakley: CREST across facing what maybe a meter meter and a half, on most of these are the most joey.
Joey Marsalisi: yeah roughly roughly a meter two meter and a half.
Bryan Oakley: Any other questions.
Bryan Oakley: For all getting that point we need another cup of coffee to wake up.
Rose Palermo (she/her): megan on the chat.
Bryan Oakley: Oh sorry.
Joey Marsalisi: yeah he's got that one.
Bryan Oakley: Guy i'm so let me try, let me just read if everybody is there any interest in keeping the inlet open, do you think it will be dredged okay go ahead.
Joey Marsalisi: yeah so um that was one of the one of the kind of purposes for looking into this a little bit on, there is a lot of interest in keeping me in the open.
Joey Marsalisi: Due to the the ecology, the kind of very unique ecology for the short bird species and horseshoe crabs, in particular in that area if it if it did close off there's potentially potential for it to go anoxic which wouldn't allow for anything to live anywhere in it.
Joey Marsalisi: So that that's kind of up for debate if it would be dredged to keep it open in the future there's kind of different viewpoints on on the benefits and and minuses to doing that so.
Bryan Oakley: that's a good answer Joe and the answer is, I don't know what the managers down there would do if this actually closes it's an interesting little system and we spend time on it, because it's it's a nice undergraduate.
Bryan Oakley: Project area but it's also a really dynamic little system, the spit that encloses the lagoon was basically gone following sandy and and it's reformed and linkedin considerably since then.
Bryan Oakley: But it's also got this dynamic where the spit In closing, it is, it is migrating to the north and also elongating so you're kind of losing title prison over time.
Bryan Oakley: and eventually it'll probably become a closed off pond although we're not quite there yet, so I don't know what they'll do.
Bryan Oakley: I was down there, the other day we're going to start some fieldwork up again pretty soon and it's it's changed even more since since joey survey so stay tuned on that for future GSA.
Bryan Oakley: Any other questions.
Bryan Oakley: All right, well nice job joy.
Joey Marsalisi: Thank you.
Bryan Oakley: i'll just make a bug both Joe and Greg are now out and into the real world so watch out here, Russia worlds here they come.
Bryan Oakley: So I appreciate everybody hanging in there we're still at 28 participants that's awesome our numbers have been very steady as we go along.
Bryan Oakley: So.
Bryan Oakley: We will hang out for better another minute to get started with our our final presentation, which is going to take us to a slightly different environment, but in a very cool poster so hang out there for another minute or so guys.
Bryan Oakley: Alright, we will go ahead and get started our last presentation by Jamie a sauna and her colleagues of Queens college and a whole bunch of other places it's going to look at earthquakes from sediment within the Japan trench market So here we go.
Bryan Oakley: hi my name is Jamie aside and today i'll be sharing the findings of the 2011 Japan earthquake and tsunami event.
Bryan Oakley: And to deposition environments, being the soap in the trench the name of the project is called extracting the deep marine record of earthquakes from the Japan trench margin sentiments.
Bryan Oakley: The main objectives of our study is to document what is known about the 2011 to include and deposit.
Bryan Oakley: to learn from the from the mythology so as to characterize the history of Paleo earthquakes in the Japan trench and other settings.
Bryan Oakley: documented processes by which homogenized that are positive and they're linked to the 2011 tohoku earthquake homogenized or take one to seven meters with the logically homogeneous I like biodegradation and our acoustically transparent.
To give a background of the tectonic plates and rates from the 2011 Tokyo earthquake tsunami event.
be catastrophic tohoku earthquake and tsunami MAC two night event occurred on march 11 2011 and the Japan trench.
The Pacific plate some facts beneath Oscar play at 8.2 centimeters per year, the rupture we should trench and slip increased up to develop should cause for the play to move 50 meters horizontally and seven meters vertically.
During the 2016 r&b song 251 expedition course we're extracted from to deposition environments being built into.
The study area was a northern central and southern regions of these two deposition environments that are near the rupture in the area maximum slip.
First study will you shortly live very new isotopes to track the earthquake deposits, such as blood cesium 137 and cesium 134.
So you see 137 and CC and 134 after the oceans and sentiments after the Fukushima power plant accident, we interpreted identifying each other's lunch earthquake event, if the presence of cesium 137 and cesium 134 found together in the core.
The core showed just cesium 134 seven we interpreted as an older deposit from the 1960s or cesium 137 was exposed to the atmosphere and due to nuclear testing that peach the 1960s cesium 137 and CC and 134 have a half life of three years, so only traces are today.
In terms of the signature of the 2011 event deposit and Steve parts, the soap we identify areas where the 2011 event was the positive, because the sediments either contained shortly live radio isotopes or not.
The steep areas of the soap gin preserve the 2011 event deposit here's an example of a core extracted from the sexual so that showed that the short liberty isotopes were absent and therefore did not record the two dozen them to include event deposit.
Bryan Oakley: The minimum deposit was absent in the northern and central trench regions, the northern region and extracted core shows march 9 and terminates using shorten liberty isotopes the lead that was found with data to be older than 2011 because of his lower concentration.
And the central trench It also showed terminates and homogenized and the lead was also found to be older than 2011 and because there was peak traces of cesium 134 we interpreted as to be possibly from 1916.
However, because it's not paired with cesium 137 we cannot define it as the 11 event deposit.
The areas that didn't show the 2011 event deposit was the area maximum slip and the sun, the trench.
The lead that was found in the down soma maximum slip show about the it was younger and we interpreted it as that you didn't love him because it was also parent with cesium 137 and cesium 134.
Therefore, we can define that the event deposit is present the downslope area maximum slip also show homogenized and sandy turbid is present.
And the southern trench is where the 2011 accumulated in the Boston because the trench deepens going north to south 2011 was perfectly preserved and thick deposits here in this region is where the biggest tomorrow night was present.
To conclude, our findings, the 2011 22 earthquake deposit was absent from steep areas so.
It was President downslope the area maximum slip and in the summer segment of the Japan trench terminal Boston.
It was absent from the northern and central segments on the trench distilled from the area maximum slip the grain size variability show, but the soap mythology contained 25 to 50% stand all the trench mythology is find a grade and compose a 40 to 60% stilt 20% stand and clay.
The grain silos differences between homogenized intimidate are very homogenized composer stilton clay all turbid is composed of sand and still that are normally graded the international ocean discovery expedition 386 will take place and.
To continue to test hypothesis hypothesis, thank you.
Bryan Oakley: All right, thank you for that Jamie.
Bryan Oakley: Do we have any questions for her.
Bryan Oakley: questions.
Justin Shawler: Sure, I have a question, Brian.
Bryan Oakley: Thanks justin God.
Justin Shawler: yeah great presentation Jamie that was excellent and really nice to see a sort of non us non east coast site to.
Justin Shawler: And I think you kind of touched on this in your proposed process a little bit or processes.
Justin Shawler: We can you speak more of what you think is driving the.
Justin Shawler: location, that you see the deposits in.
Justin Shawler: Like is it is it all process driven or is it also source driven are there sort of differential responses to.
Justin Shawler: The earthquake itself in terms of what is able to be transported, or do you think it's purely driven by like they're just being a good DEMO Center for the materials.
Jamie A.: yeah so on the trench deepens from north to south, and so, if you could see like you can see from the poster do the images.
Jamie A.: At immediately accumulated and the southern bhasin because it deepens from north to south, and so what we think resulted in these homogenized.
Jamie A.: Is that um you so you have the earthquake, and you have the shaking.
Jamie A.: And it was a high magnitude earthquake, so it was nine so it would produce long ways and these ways will have a much longer frequency, so the frequency is not as high a smaller earthquakes.
Jamie A.: So what happens is a sediment is loose on the slope is shaken and we suspend it and we think that it's the entrainment process that leads to the Hamas homogenization of the settlements.
Justin Shawler: Question it does, thank you.
Bryan Oakley: Any other questions for Jamie I mean i'll just say it again, they said all of the posters good fat fabulous, this is a really well laid out poster it was I was very easy to follow when I was looking at it last night of my iPad Thank you.
Bryan Oakley: Any other questions.
Bryan Oakley: All right, well.
Bryan Oakley: I appreciate everybody with their contributions great job and.
Bryan Oakley: If anybody want to hang and ask any questions right and speakers, I think we can stand here for a little while otherwise.
Bryan Oakley: enjoy the rest of the conference and it says on the board, I hope to see everybody back in national on ground in the fall i'm looking forward to hopefully getting back out there and in person meeting, even if it means drinking hotel coffee.
Justin Shawler: I wanted to take a minute to thank you for your leading of the organizing of this session it's been a lot of fun to join you and we want to thank you for including all of us, but you've really taken the lead and we really appreciate that it's been excellent.
Bryan Oakley: Thank you it's it's a lot less work with an online conference and on ground for at least for me, I know, in the background for all the GSA folks it's a shit ton more work but.
Bryan Oakley: For us it's a.
Bryan Oakley: It was a lot easier so i'm happy to do it and I appreciate everybody contributing so.
Bryan Oakley: Alright, I guess, I guess that's it so.
Bryan Oakley: Hopefully we'll see everybody in person next time.
Bryan Oakley: And those of you that I said i've reached out to the paper or figure, something I will.
Bryan Oakley: Thanks Linda.
Ilya V. Buynevich: Thank you.
Bryan Oakley: Thanks honey i'll see you soon.
Bryan Oakley: it's good to see even though we're not in person, oh yeah.
Bryan Oakley: i'm good job to all the students you guys really rocked today.
Ilya V. Buynevich: Well done well done.
Christopher Hein?he/him: really nice put together meeting this is, this is a lot of fun great way to spend the Sunday morning.
Bryan Oakley: It was a good way to spend a Sunday morning wasn't a Chris what.
Alice Staro: You were asking about the measures that they use for the remote sensing analysis.