Authors
Tyler L. McIntosh (CIRES,Earth Lab), Laura E. Dee (CU Boulder), Kyle Manley (CIRES,Earth Lab), Ty Tuff (CIRES,ESIIL/Earth Lab), Cibele Amaral (CIRES,ESIIL/Earth Lab), Ginikanda Ilangakoon (CIRES,ESIIL/Earth Lab), Robbie Andrus (Washington State University), Jennifer K. Balch (CIRES,ESIIL)
Abstract
The occurrence of wildfires, bark beetle outbreaks, and droughts are natural phenomena in the Western United States, and forested ecosystems have evolved to be resilient to their occurrences. However, climate change is shifting the presence and severity of these events. Disturbances can interact with one another in complex ways that we have only recently begun to quantify. Initial disturbances can impact both forest vulnerability to subsequent events as well as the characteristics of subsequent events, while event sequencing can shift seed presence and seedling establishment conditions. When impacted by disturbance prior to or following wildfire, localized studies at the scale of single or several events have put the long-term resilience of forested systemsâand the wide variety of ecosystem services that they provideâinto question. Our work expands upon this foundation to investigate the consequences of interactions between three disturbance agents (drought, insect outbreaks, and wildfire) on forest resilience across broad geographic scales, enabling understanding of forest dynamics in a wide range of contexts. We leverage empirical remotely sensed data across disturbance events in the western U.S. from 2000-2023 to a) test the overall effect of pre-fire disturbance on long-term ecosystem resilience, and b) identify the spatial heterogeneity of these effects.