Mathematical Biology Seminar Jon Wang, UU Biology Wednesday, March 1, 2023 3:05pm in LCB 225 Rapid transformations of terrestrial ecosystems and the carbon cycle by intensifying wildfire: cases in Canada and California Abstract: Climate change and intensifying wildfires are driving hot spots of ecosystem change in climate-sensitive regions, potentially transforming once reliable carbon sinks into new carbon sources. By analyzing time series of satellite-based remote sensing data, I characterized land cover, carbon, and disturbance dynamics across multiple decades and at high resolutions in two particularly sensitive regions: the temperature-limited northern high latitudes and water-limited Californian mountains. In Alaska and Western Canada, wildfires have initiated widespread shifts in forest composition and, despite recent greening trends, a suppression of the aboveground carbon sink that is not captured by Earth system models. In California, recent megafires have reversed decades of forest growth and may be initiating biome shifts as dense forests are threatened by severe burns and struggle to recover. Regional carbon dynamics will be fundamentally altered by widespread shifts fire regimes and forest demography, threatening the sustainability of carbon offsets programs intended to reduce net fossil fuel emissions.