What drives low-severity fire in the southwestern USA?
The authors evaluated both climate and biophysical factors that influence the occurrence of low severity fire in the Southwest. Low severity fire is an important component of many high frequency, fire-adapted ecosystems in the southwest, so understanding those conditions which promote low severity fire is highly relevant to land managers.
The presence of live fuel was the most influential factor in predicting low-severity fire followed by year-of-fire climate. They found that as live fuel decreased, the likelihood of low-severity fire increased, i.e. a reduction in fuel reduced fire severity. Low severity fire also increased as temperatures and the climatic moisture deficit decreased. Topography and longer-term climate factors were not important predictors of low-severity fire.