Constraints on global fire activity vary across a resource gradient
The authors examined the potential relationship between global fire activity and biomass resource availability based on monthly soil moisture metrics before and during the fire season. They also examined the efficacy of a potential global fire weather metric, anomaly in mean monthly 500 hPa geopotential height.
The authors' results support the varying constraints hypothesis that wildfire occurrence requires key biophysical factors to coincide, however, the relationship between fuel moisture and fuel availability varies along fairly predictable spatial patterns. In areas where fuel is abundant, fuel moisture availability has the strongest constraint on fire activity, whereas in fuel-limited systems, fire is constrained more strongly by fuel availability. In these ecosystems, lagged fuel moisture is more representative of subsequent potential fire activity.
Climate and Fire Linkages
The authors' results support the varying constraints hypothesis that wildfire occurrence requires key biophysical factors to coincide, however, the relationship between fuel moisture and fuel availability varies along fairly predictable spatial patterns. In areas where fuel is abundant, fuel moisture availability has the strongest constraint on fire activity, whereas in fuel-limited systems, fire is constrained more strongly by fuel availability. In these ecosystems, lagged fuel moisture is more representative of subsequent potential fire activity.