Wildland fire as a self-regulating mechanism: the role of previous burns and weather in limiting fire progression
The authors’ objective was to research the ability of wildfire to limit the spread of a subsequent fire based on the time between the two, and also to see how weather at the time of the fire alters this effect.
Stands that are within unaltered, short-interval fire regimes tend to self-regulate the burn severity of secondary fires, and burn at the same or lower severity, suggesting that the initial fire moderated the burn severity of the second fire. However, this effect decays as time since fire increases. Specifically, the drier forests of New Mexico, the ability of wildfire to act as a fuel break decayed after only 6 years. Weather conditions conducive to fire ignition and spread, however, can weaken the effect of a previous reburn to limit fire spread or severity.
Climate change is expected to increase the frequency of extreme fire weather events, likely reducing the effectiveness of fire-created fuel breaks during extreme fire seasons. Still the authors suggest that using fire to regulate future fire severity may present opportunities to increase ecosystem resilience to future fire, especially in non-extreme fire years.