Predicting Future, Post-fire Erosion & Sedimentation with Watershed Models in the Western USA

When: Wednesday February 22, 4:00 PM
Where: NAU School of Forestry, Room 017
Speaker: Dr. Joel Sankey, USGS

Abstract

The area burned by wildfires has increased in recent decades and is expected to increase in the future for many watersheds worldwide due to climate change. Fire affects soils in many ways, and one particularly important effect is that burned areas within watersheds increase soil erosion rates, which can increase the downstream accumulation of sediment in rivers and reservoirs. Using an ensemble of climate, fire, and erosion models, we have shown that post-fire sedimentation is projected to increase for more than three-quarters of watersheds by at least 10 percent and for more than one-quarter of watersheds by at least 10 percent by the 2041–2050 decade in the western USA. In this region, 65 percent of the water supply originates from forested lands that are prone to wildfire, and many of the watersheds with projected increases in sedimentation are important headwaters of rivers and reservoirs that meet water demands of downstream users.

In this presentation, Dr. Sankey will discuss the caveats associated with these recent projections and explain several important hurdles that scientists still must overcome to provide truly comprehensive projections of future sedimentation associated with increased wildfire. He will also explain some the practical ways in which projections of future, post-fire sedimentation might be used for resource management.

Speaker Bio

Joel Sankey is a Research Geologist for the USGS, Grand Canyon Monitoring and Research Center, and the Southwest Biological Science Center in Flagstaff. He is also an adjunct professor of the School of Earth Sciences and Environmental Sustainability at NAU. Previously, he was a Mendenhall Fellow with the USGS Western Geographic Science Center located at the UA. Joel has a Ph.D. in Engineering and Applied Science from the Geosciences Department at Idaho State University. His research expertise spans the disciplines of geomorphology, soil science, landscape ecology, and remote sensing. He conducts interdisciplinary science to detect, monitor, and provide bio-geo-physical explanation for disturbance, resilience, and changes in soil, sediment, and vegetation. His research focuses primarily on resource management and conservation issues throughout the western USA, particularly in arid and semi-arid systems and rivers.