Wildfires destroy millions of acres of land each year in the United States, costing billions of dollars and sometimes resulting in damaged homes and lost lives. Researchers are beginning to explore how soil moisture, particularly in the zone where plant roots reside, can influence wildfire probability. Although researchers have intuitively understood the relationships between soil moisture, fuel conditions, and wildfire occurrence for some time, only recently has the increasing availability of soil moisture data enabled a better understanding of these relationships.

With this information becoming more prominent, the International Association of Wildland Fire (IAWF) hosted a workshop in April to raise awareness within the fire management community about how soil moisture data could be used in wildfire modeling, risk assessment, planning, and decision support tools. 34 researchers and fire management practitioners participated in the 1-day workshop, which included guest speakers and group discussions on wildfire impacts, current modeling trends, and needs related to fire management decision-making.

Discussions revealed that fire management decision-makers are not seeking soil moisture information or are unaware of recent research indicating the supplementary benefits of such information when predicting fire danger. Instead, they often rely on decades-old drought indices. As a result, participants identified a need for increased accessibility of soil moisture information at relevant spatiotemporal scales and to determine how this information can effectively be integrated into existing fire danger rating systems.

This study was funded in part by the South Central Climate Adaptation Science Center. Their project, Wildfire Probability Mapping Based on Regional Soil Moisture Models, was initiated in 2017 to (1) develop an effective model of soil moisture for the Red River and Rio Grande basins, (2) document relationships between modeled soil moisture and wildfire probability, and (3) map soil moisture distribution and wildfire probability in the Red River and Rio Grande basins.