HOLOCENE DROUGHT PROCESSES, COMMUNITY RISK PERCEPTION, AND PREPAREDNESS IN WYOMING HEADWATERS

Climate change has and will continue to increase environmental hazards, with impacts on vulnerable, rural and minoritized populations. In the Western U.S., impacts to water resources exemplify an environmental hazard enhanced by climate change. Within the region, Wyoming has a unique geographic backdrop that includes headwaters of three major river basins (Snake/Columbia, Green/Colorado, and Platte/Mississippi), with associated rural communities. This research focuses on the spatial and temporal variability of atmospheric processes associated with recent droughts impacting Wyoming’s headwater regions. We identified recent anomalous dry years from precipitation time series and used data from the ERA5 project to analyze climate variables associated with precipitation processes during selected dry years. Seasonal composite anomalies were calculated for precipitation rate; specific humidity at 850hPa; geopotential height at 500hPa; and omega at 500hPa. The composite-anomaly values represent the selected cases (e.g. drought years) compared to long-term means (e.g. average conditions) to provide information on atmospheric processes associated with persistent drought conditions in the region. Our results use modern climate data to understand drought processes that can be applied to paleo-environmental, present, and future hazards. We use our results from our climate analysis of recent drought, as well as future temperatures from CMIP5 data, to develop graphics for use in community-based focus groups to assess community members' perception of past and future drought risk. Holocene climate change (e.g. enhanced drought) both recent and future will impact communities regionally. Through coding responses from community-member focus groups, we use analysis of variance; and cluster analysis for individual basins and between basins to identify community perception of drought risk. Our research provides a bridge between Holocene climate processes and perceived risk within rural communities to assist in the development of community preparedness to extreme events like drought.