Are the massive fires burning across Southern California a product of global warming? Scientists said it would be difficult to make that case, given the dangerous mix of drought and wind that has plagued the region for centuries or more.

But they said the extreme conditions that stoked the wildfires could become more common as the world warms. Research suggests that rising temperatures are already increasing fire damage in many parts of the West.

In a study published last year in the journal Science, researchers looking at Western federal forests found nearly seven times more land burned from 1987 to 2003 than in the previous 17 years.

The analysis mainly attributed this to a 1.5-degree rise in average spring and summer temperatures. With spring arriving earlier and snow melting faster, the forests dried out sooner, extending the average fire season by more than two months.

The study, however, found Southern California was different from the rest of the West, with no increase in the frequency of fire as temperatures rose.

“In Southern California, it’s hot and dry much of the year,” said Anthony Westerling, a climate scientist at UC Merced and the study’s lead author. In other words, Southern California was already perfect for fire.

“That is a fire-prone environment regardless of whether we are in a climate-change scenario,” said Tom Wordell, a wildfire analyst at the National Interagency Fire Center in Boise, Idaho.

But eventually global warming could make Southern California’s occasional droughts more persistent, exacerbating the fire danger. Conditions as dry as the Dust Bowl of the 1930s could prevail in the Southwest by the middle of this century, according to a study published this year in Science.

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