Tuesday, January 23, 4:00 to 5:00 pm
Why have humans lost control of wildfire in the western United States?
Park Williams
UCLA Professor of Geography, Hydroclimatologist, 2023 MacArthur Fellow
Crocker Science Center, Room 206
Since the mid-1980s the annual area burned in the western U.S. has increased by approximately 300%. In forested areas, the increase has exceeded 1000%. Simple statistical relationships between fire activity and climate strongly suggest that this increase has been largely driven by warming and drying trends. Climate models indicate anthropogenic climate change as an important contributor to these trends. However, these results paint an overly simplistic picture. Fuel characteristics, ignitions by human, and firefighting also critically impact wildfire, and modulate the way in which climate affects wildfire. Further, these processes are highly heterogeneous geographically and have changed substantially in many areas over the past century. In this talk I will use a new, spatially explicit forest-fire and ecosystem model to assess of the magnitude and geography of the contribution of anthropogenic climate change to western U.S. forest-fire activity since the 1950s and how climate change is likely to affect forest fire, carbon, and ecosystems over the remainder of the 21st century.
Bio:
Park Williams is a hydroclimatologist whose research aims to understand the causes and consequences of hydrological extremes such as drought. Much of his research focuses on hydroclimatology in its own right, and much also aims to improve understanding of how hydrological extremes affect life on earth (bioclimatology). Questions that he finds especially interesting involve the effects of human-caused climate change on the hydrological cycle, ecological systems, and humanity through extreme events such as heat waves, wildfires, and flooding.