EXAMINATION OF PERSISTENT SLAB AND STORM SLAB AVALANCHES THROUGH THE USE OF AERIAL IMAGERY TO UNDERSTAND THE EFFECTS OF CLIMATE CHANGE, LAKE CITY, COLORADO

There has been a steady trend of declining annual precipitation in the Henson Creek watershed over the past 40 years. In 2019 there was a spike in precipitation that was lower than past high snowfall years, but produced significant avalanche activity. By analyzing historic climate data and aerial imagery we are able to identify when past avalanches might have occured; similar to the avalanches that were recorded in 2019. Historic records of avalanches for earlier decades at the study area are unavailable.

Climate data was obtained for the past 40 years from the PRISM database, and it was used to find the peak snowfall events for each year. Examining the change in temperature between these peak snowfall events gave us an idea of when it was most likely for an avalanche to occur. Correlating these events with aerial imagery we were able to identify historic avalanche activity. The analysis conducted in this study could be used to better predict future avalanche activity in the backdrop of climate change.