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Fire-southern oscillation relations in the southwestern United States

Thomas W. Swetnam, Julio L. Betancourt


Summary - what did the authors do and why?

The authors correlated fire scars and tree-ring growth to assess potential relationships between fire and climate across pine forest ecosystems in the Southwest.

Publication findings:

The authors found strong relationships between area burned and highly positive values of the Southern Oscillation index (SOI), which is associated with reduced rainfall and severe winter-spring drought in the Southwest. They also found regional synchrony of large fires during the high-SO phase, which is associated with limited spring precipitation resulting in reduced tree growth. This suggests that seasonal climate, and not just local weather conditions, affect fire activity at a regional scale.

Climate and Fire Linkages

The authors found strong relationships between area burned and highly positive values of the Southern Oscillation index (SOI), which is associated with reduced rainfall and severe winter-spring drought in the Southwest. They also found regional synchrony of large fires during the high-SO phase, which is associated with limited spring precipitation resulting in reduced tree growth. This suggests that seasonal climate, and not just local weather conditions, affect fire activity at a regional scale.

The authors found strong relationships between area burned and highly positive values of the Southern Oscillation index (SOI), which is associated with reduced rainfall and severe winter-spring drought in the Southwest. They also found regional synchrony of large fires during the high-SO phase, which is associated with limited spring precipitation resulting in reduced tree growth. This suggests that seasonal climate, and not just local weather conditions, affect fire activity at a regional scale.