How have wildfires affected forest basal area in Northern and Southern California during the 21st century?

Abstract

Wildfires are unplanned and dynamic fires that occur in areas of combustible vegetation. They can be natural or human-induced and play a vital role in ecosystem health. The severity and intensity of wildfires can change over time based on the weather, available fuel and topography. California is continuously experiencing longer wildfire seasons as a direct result of climate change, affecting the forest structure of the state’s forest. Forest basal area is used to determine forest stand density and is an indicator of annual growth potential (Nix, 2020). It is often used as the basis for making important forest management decisions. My research will determine how wildfire frequency and extent have affected the basal area of Northern and Southern California’s forests in 2000 and 2017. Fire perimeter and frequency data obtained from the United States Forest Service regional datasets website will be used to define fire characteristics in the regions. Tree basal area data obtained from the United States Forest Service regional-level datasets website will be used to quantify the basal area of critical forest types. Percent change in basal area, fire frequency and acres burned each year will be determined to compare the burn regimes of the two regions during the two years to see how that has impacted the forest’s basal area. The findings will give an idea of how the rate of wildfires has changed in the last two decades and its subsequent impacts, which can help us better prepare for the future of forests in an ongoing climate crisis.