MONITORING VEGETATED DUNE FIELDS FOR THRESHOLD RESPONSES TO CLIMATE EXTREMES

Vegetated dune fields and sand sheets cover nearly 11% of the North American Great Plains serving as important rangelands, croplands, and energy production and transmission corridors. These landscapes are additionally important archives of climate change and variability in that the processes responsible for their formation and evolution are directly tied to climate. Despite abundant research on the links between these landscapes and climate, little work has been done to identify the regional climatic thresholds responsible for resulting change in a dune field landscape. Here we present a preliminary assessment of a larger research project aimed at providing new and transformative approaches for evaluating historic and modern dune activity, with the goal of identify activation thresholds that can be incorporated into climate models to provide better predictions for the potential of future dune activity. Data collection includes the use of several remote sensing platforms at various spatial resolutions and temporal coverages. Fine scale satellite and aerial photograph data will drive a percolation model of dune activation, from which coarser Landsat data with global seasonal coverage can be used to detect and model the last 40 years of dune field change. This model will produce a multi-scale analysis of vegetated dune dynamics which will be compared to climatic data over a series of time scales to asses dune system response to climate variability, in particular extreme shifts in temperature and precipitation. Data derived from this research will be incorporated into a wide range of IPCC scenarios to assess the potential for future dune activity in the Great Plains.