SPATIAL AND TEMPORAL TRENDS OF WILDFIRE OCCURRENCE IN WASHINGTON, USA: IMPLICATIONS FOR FUTURE RISK REDUCTION

Abstract

The patterns in fire occurrence and acres burned by wildfire in the state of Washington, USA have been in flux since the late 19th century. In the past 100 years, fire suppression, land use practices, societal expansion, and climate change have altered the forest, shrub, and grassland ecosystems of Washington which has resulted in higher risk of severe fire. This article outlines the changes in the fire regime that occurred with the arrival of European and American colonizers in Washington and uses spatiotemporal analysis techniques to investigate how the fire regimes are changing in the present day (1992-2020). My results identify specific areas in Washington where the count of large fires (>300 acres) and the total acres burned per year are increasing, both in the forestland and the grassland. I discuss the implications for wildfire vulnerability and risk reduction practices in Washington, highlighting the successes of current forest treatment strategies and areas of improvement for wildfire risk reduction in the grassland.