Data from: Contemporary fires are less frequent but more severe in dry conifer forests of the southwestern United States

Wildfires in the southwestern United States are increasingly frequent and
severe, but whether these trends exceed historical norms remains
contested. Here we combine dendroecological records, satellite-derived
burn severity, and field measured tree mortality to compare historical
(1700-1880) and contemporary (1985-2020) fire regimes at tree-ring
fire-scar sites in Arizona and New Mexico. We found that contemporary fire
frequency, including recent, record fire years, is still <20% of
historical levels. Since 1985, the fire return interval averages 58.8
years, compared to 11.4 years before 1880. Fire severity, however, has
increased. At sites where trees historically survived many fires over
centuries, 42% of recent fires resulted in high tree mortality. Suppressed
wildfires tended to burn more severely than prescribed burns and fire use
wildfires. These findings suggest that expanded use of low-severity
prescribed and managed fire would help restore forest resilience and
historical fire regimes in southwestern dry conifer forests.