A major climate oscillation in the Southern Hemisphere is expected to intensify in the coming decades, likely increasing wildfire activity in the southern half of South America. This 2010 photo shows the aftermath of a wildfire outside the town of Futaleufu in southern Chile.
The new findings are based on analysis of tree rings dating to 1506. Researchers used the data to track past wildfire activity in the forests of Patagonia tied to the Southern Annular Mode, or SAM, a climate oscillation that creates low atmospheric pressure in the Antarctic that is tied to warmer and drier conditions in southern South America. The tree rings showed that when SAM was in its positive phase, there were widespread fires in both dry woodlands and rainforests in Patagonia, a region that straddles Argentina and Chile, says Andres Holz, lead study author and a research associate at the University of Colorado-Boulder.
“Our study shows for about the past 250 years, the Southern Annular Mode has been the main driver in creating droughts and fires in two very different ecosystems in southern South America,” says Holz. “Climate models suggest an increase in SAM beginning in the 1960s due to greenhouse gas increases and Antarctic ozone depletion probably will cause this region to be drought-prone and fire-prone for at least the next 100 years.”
Full story at Futurity.
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Photo credit: Andres Holz