Speaker: Charles Jones
Affiliation: Department of Geography and Earth Research Institute (ERI), UC Santa Barbara
Abstract:
The many tragic examples of wildfires in California underscore the importance of understanding the relationships among climate, extreme fire-weather, fire ignitions (especially by the electric grid infrastructure) and vegetation management. I will discuss research results from an ongoing project funded by the UC Lab Fees program. The main objectives of this project are:
1) understand the nature of recent changes in extreme fire-weather regimes in California
2) determine wildfire-risks associated with the electric grid in California
3) develop an optimal coupled-fire-weather-grid model for de-energization operations
4) economic cost assessments of public safety power shutoffs (PSPS) and vegetation management strategies.
In this talk specifically, I will first discuss the August-complex wildfire in 2020, which is the largest wildfire in recorded history in California. A wildfire spread model is used to simulate the explosive growth of the Doe fire, which eventually morphed with other fires within the August-Complex fire. Sensitivity analysis to air temperature and fuel moisture content will be presented. In particular, the effect of ignition time relative to the heat waves occurred during August-September 2020 show marked impacts in fire growth and fire radiative power. Next, I will discuss the Camp fire during November 2018. A wildfire spread model is used to investigate the effectiveness of fuel break in the wildland urban interface (WUI) in slowing down the spread of the fire towards the city of Paradise. Lastly, I will discuss the importance of surface winds and their critical role in wildfires. I will show statistical analyses based on reanalyses products and surface weather stations to identify potential changes in surface winds in California.