The authors used satellite data to measure areas of more than 1,000 acres burned by large fires from Nebraska to California since 1984. They found that the total area consumed each year increased at a rate of about 90,000 acres per year through 2011. That’s a Las Vegas-size increase every year for almost two decades.

The hardest-hit areas were the Sierra Nevada and Arizona-New Mexico Mountains; the deserts of the Southwest; and the Southern Plains, across west Texas, Oklahoma, Kansas and eastern Colorado.

The increase, they reported, corresponded with rising temperatures and increasing drought conditions in the West likely brought on by “large-scale climate changes.”

Since those conditions are projected to become more severe, so will the fires, the authors said.

Ironically, attempts to suppress fires over the past few decades are probably contributing to the increase in wildfires because there’s more fuel left to burn than naturally occurring fires would have left behind.

“It could be that our past fire suppression has caught up with us,” said Jeremy Littell of the U.S. Geological Survey on the AGU’s Web site.