The impact of fire on active layer thickness we propose to perform large-scale surveys of ALT in the YK delta fire zones using ground penetrating radar (GPR) and probing supplemented by observations…

This is a $113,703 cooperative agreement awarded by the National Aeronautics and Space Administration (NASA) to the University of Colorado to conduct research on the impact of wildfire on permafrost active layer thickness (ALT) in the Yukon-Kuskokwim Delta region of Alaska. The University will use ground-penetrating radar and other field measurements to gather approximately 30,000 ALT data points both within and outside fire-affected areas. The goal is to statistically determine how fire impacts permafrost thermodynamics by testing hypotheses related to the relationship between ALT, organic layer thickness, and burn severity. This contract is not associated with a larger vehicle and does not have a set-aside designation. As a leading public research university, the University of Colorado has extensive experience conducting Earth science, climate, and environmental research under past federal awards from agencies like NASA, the Department of Defense, and the National Oceanic and Atmospheric Administration.

The impact of fire on active layer thickness we propose to perform large-scale surveys of ALT in the YK delta fire zones using ground penetrating radar (GPR) and probing supplemented by observations of volumetric water content (VWC), organic layer thickness (OLT), and burn severity. GPR uses pulsed, radiofrequency electromagnetic waves to noninvasively image the subsurface and is an effective tool to quickly map ALT over large areas schaefer ET AL., 2015; chen ET AL., 2015A]. Our goal is to gather ~30,000 ALT measurements both within and around the YK delta fire zones to create a dataset suitable to statistically determine the impact of fire on permafrost thermodynamics. The question we seek to answer is how does fire impact ALT? We hypothesize that 1) ALT is proportional to OLT and 2) the change in ALT is proportional to burn severity. We will quantify the change in ALT due to fire by comparing measured ALT values within and outside the fire zones. We will test hypotheses 1 and 2 using statistical comparisons of ALT, OLT, and burn severity for different vegetation types.