Smokey the bear working overtime.

• Position: YOUR LIFE - Brief article

Large forest fires have occurred more frequently in the West since the mid 1980s as spring temperatures increased, mountain snows melted earlier, and summers got hotter, contend researchers at the University of Arizona, Tucson. Almost seven times more forested Federal land burned during the last 20 years than during the prior two decades. In addition, large fires occurred about four times more often during the latter period.

The research is the most systematic analysis to date of recent changes in forest fire activity in the western U.S. The increases in fire extent and frequency strongly are linked to higher March-through-August temperatures and are most pronounced for mid-elevation forests in the northern Rocky Mountains.

"I see this as one of the first big indicators of climate change impacts...