The Dolan Fire of Central Coastal California: Burn Severity Estimates from Remote Sensing and Associations with Environmental Factors
In 2020 wildfires scarred over 10,000,000 acres in the western United States, devastating urban populations and ecosystems alike. The significant impact that wildfires have on plant, animal, and human environments makes wildfire adaptation, management, and mitigation strategies a critical task. This study uses Landsat satellite imagery to calculate burn severity and vegetation health indices and map the fire progression for the Dolan Fire of central coastal California. Several environmental factors such as temperature, fire fuel, topography, and wind speed and direction are known to affect wildfire spread and burn severity. The aim of this study is investigating the relationship between these environmental factors and estimates of burn severity for the Dolan fire scar. Burn severity is calculated using the Difference in Normalized Burn Ratio (dNBR) and classified into 4 classes before being mapped at a series of time steps. The Dolan fire was a generally moderate severity burn with average dNBR of 0.290. Ignition site location paired with the patterns of fire spread are consistent with wind velocity data suggesting fire movement to the southeast of the fire perimeter. Patterns of increased burn severity are seen with both topography (slope and aspect) and fuel type. Long needle timber litter and mature timber fuels along with areas of intermediate slope angles between 15°-35° were found to be more susceptible to high burn severity. This study has implications on future predictive modeling of wildfires that may serve to develop wildfire mitigation strategies, manage climate change impacts, and protect human lives.