As our climate changes, people are becoming increasingly worried about wildfires west of the Cascade Mountains in Oregon and Washington, and the risk these wildfires pose to human communities and forest resources in this area. Because there have been so few large wildfires in the last century in this region, it is difficult to know, in this area specifically, how climate change is expected to affect wildfire potential. Historical records show that very large wildfires were a major force in shaping regional forests and suggest they will continue to in a warming future.

The goal of this research is to improve our knowledge of how future changes in the climate will affect wildfire potential in western Washington and northwestern Oregon. We are looking at both smaller (fewer than 25,000 acre) and larger (greater than 25,000 acre) wildfires, such as those that burned in the late 1800s and early 1900s in this region. We want to understand the key climatic ingredients that enable these wildfires, so that we can better understand future change in wildfire potential in a changing climate.

The need for wildfire risk reduction activities in areas with more frequent wildfires, such as eastern Washington, is clear and urgent. In western Washington and Oregon, the urgency and need are less clear given the relatively infrequent occurrence of these events. Improving our understanding of future wildfire potential in this region will support land and emergency managers in prioritizing fire risk reduction activities. This information will guide decisions including to what extent and where it is most important to implement risk reduction efforts in western Cascadia.

Using statistical models developed from records of historical climate and wildfire area burned, we will quantify the extreme weather conditions such as late summer drought, high temperatures, and dry east winds under which these wildfires burned. After identifying the climatic conditions that were most important for wildfire historically, we will use projections from regional climate models to quantify the changing likelihood of these conditions in the future. Although multiple studies have evaluated the relationships between climate and wildfire across the western US, our study will focus specifically on the region west of the Cascade Mountains where wildfire is less frequent, making these relationships poorly understood to date.

Managing Western Wildfire Risk in a Changing Climate. The Climate Impacts Group and the Northwest Climate Science Adaptation Center convened regional partners to discuss the increasing risk of wildfires in western Washington, and opportunities for adaptation actions.

The Harvey Lab. The core mission in the Harvey Lab is to conduct cutting-edge scientific research in forest, landscape, and disturbance ecology.