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More photos of Big Sur. Everybody is on the way out.
The blaze had swept within a half mile of at least one major resort — the Ventana Inn and Spa — by mid-morning, as winds whipped the coast, humidity dropped and the fire grew by more than 8,000 acres overnight.
No commentary jumping out anywhere about the contribution climate change might have in all of this. So let me make sure we know what is known.
“Since 1986, longer, warmer summers have resulted in a fourfold increase of major wildfires and a sixfold increase in the area of forest burned, compared to the period from 1970 to 1986. A similar increase in wildfire activity has been reported in Canada from 1920 to 1999 (5).
Westerling et al. used the most comprehensive data set of wildfire occurrences yet compiled for the western United States to analyze the geographic location, seasonal timing, and regional climatology of the 1166 recorded wildfires with an extent of more than 400 ha. They found that the length of the active wildfire season (when fires are actually burning) in the western United States has increased by 78 days, and that the average burn duration of large fires has increased from 7.5 to 37.1 days. Based on comparisons with climatic indices that use daily weather records to estimate land surface dryness, Westerling et al. attribute this increase in wildfire activity to an increase in spring and summer temperatures by ~0.9°C and a 1- to 4-week earlier melting of mountain snowpacks. Snow-dominated forests at elevations of ~2100 m show the greatest increase in wildfire activity.”
The closing paragraph reads:
“Wildfires add an estimated 3.5 × 1015 g to atmospheric carbon emissions each year, or roughly 40% of fossil fuel carbon emissions (13). If climate change is increasing wildfire, as Westerling et al. suggest, these new sources of carbon emissions will accelerate the buildup of greenhouse gases and could provide a feed-forward acceleration of global warming.”
The full report, in Science, is here.