Custom Loss Functions in Fuel Moisture Modeling
This work addresses wildfire prediction for safety and management, but it is incremental as it builds on existing machine learning approaches with minor enhancements.
The study tackled the problem of improving wildfire rate of spread forecasts by developing custom loss functions for fuel moisture content models, focusing on dry fuels, and found that these functions slightly improved accuracy.
Fuel moisture content (FMC) is a key predictor for wildfire rate of spread (ROS). Machine learning models of FMC are being used more in recent years, augmenting or replacing traditional physics-based approaches. Wildfire rate of spread (ROS) has a highly nonlinear relationship with FMC, where small differences in dry fuels lead to large differences in ROS. In this study, custom loss functions that place more weight on dry fuels were examined with a variety of machine learning models of FMC. The models were evaluated with a spatiotemporal cross-validation procedure to examine whether the custom loss functions led to more accurate forecasts of ROS. Results show that the custom loss functions improved accuracy for ROS forecasts by a small amount. Further research would be needed to establish whether the improvement in ROS forecasts leads to more accurate real-time wildfire simulations.