JACKSON - Wyoming is the "dead center" of a scientific study released earlier this month indicating global warming is drying out areas faster, making them more susceptible to big fires, according to a University of a Wyoming ecology professor.

Stephen Jackson, professor of botany and director of the school's program in ecology, said Wyoming is one of the highest-risk areas connecting climate change and fires.

"We're really in a sense the poster child, or a poster child, for some of the trends that they are noting," Jackson said.

According to an article published in Sciencexpress.org, the online version of the journal Science, four researchers compared forest wildfire activity in the West with climate data. Since the mid-1980s, there have been more large-scale forest fires, longer duration of fires, and a longer duration of fire season. Earlier snowmelt, caused by warmer spring seasons, corresponds to increased fire activity, the researchers said.

Warmer spring seasons are caused by either global warming or an overall warming trend, the researchers said.

Jackson said the correlation the researchers noted could be "the grizzly bear banging on the cabin door."

"This could be what is telling us that climate change is really here," he said. "The public tends to take for granted that global climate change is going to be something slow and gradual. This may be indicating climate change is here knocking on the door."

Jackson went a step further, saying large fires also facilitate the invasion of other species, such as cheatgrass replacing sagebrush. Some replacement species are good, he said; others are not. But the possibility of bad replacements compounds the problem of increased fires.

The tie between early snowmelt and increased drought, and more fires, is also seen by John Lawson, area manager with the Bureau of Reclamation in Mills.

While Lawson said he is speculating, he said early runoff means that water is going directly into rivers and reservoirs, giving them a temporary boost. But precipitation coming after runoff tends to go into the ground, because the soils have dried out. Extended, and normal, melting of snows maintains soil moisture for longer in the year, more evenly distributing the moisture.

"If you can extend that (runoff) over a long period of time, you're going to keep the ground supplemented, and keep moisture content up in ground," Lawson said. "By having early melt, snow that you would expect to be there in June and July that would still keep the meadows and high-country grasses still well supplied - it's not there."

That happened this year. January and February saw snowpack levels near 130 percent of average, but by March, that number dropped to 117 percent, and by May 1 after a warm spring, that dropped to 76 percent.

"The bottom fell right out of it," Lawson said. "If you don't get the snow and take advantage of those four months of inflows (April to July), you're done."

Jackson said the amplification of the drought in Wyoming - which according to a leading drought monitor indicated the entire state was in "severe drought" last week - is "part and parcel of the same thing that's driving the fires."

Climate, not fuel?

Jackson said much of the attention on wildfires has focused on fuels, such as the Bush administration's "Healthy Forest Initiative" allowing for more logging on forests. The new study indicates that focus has been misleading, he said.

"To me, this study really shows that climate trumps fuel in fire management risk," he said. "We really have to pay very close attention to climate in our forest policy and management programs."

Still, Jackson said, just because there are dry conditions doesn't mean it is going to be a big fire year - but it increases the probability. The study also said fuels still do play a role in large fires.

Bill Crapser, Wyoming state forester, said the study is credible given what he has seen, but fire seasons are influenced more by weather.

"In the past we've had huge fire seasons, too," Crapser said, pointing to 1910. "I think weather on an individual year and drought patterns have a bigger impact, but climate change has an impact."

Another big fire year was 1988, with the fires in and around Yellowstone National Park - a time corresponding with the researchers' timetable linking climate change and fire.

"This study shows just how vulnerable we are to climate change," Jackson said.

Temperatures have risen by about .9 degree Celsius (about 1.5 degrees Fahrenheit) in the Rockies, Southwest, Northwest and Sierra Nevadas. Temperatures are expected to rise more this century.

Global warming is caused by increased carbon dioxide emissions, which cause more heat to be trapped in the atmosphere. The study said it is unclear whether the temperature changes are a result of global warming or natural temperature variations.

Burning fossil fuels including gasoline and coal are major contributors to the increased emissions, and global warming corresponds with human development.

"This is a good indicator of how a very small increase in temperature has already had a dramatic impact," Jackson said. "If the projections are correct, we're only seeing the tip of the iceberg."

Environmental reporter Whitney Royster can be reached at (307) 734-0260 or at royster@tribcsp.com.