"We're not used to hearing numbers like these, because we're not used to looking at things on a regional scale," he said.
"What we always hear about is an average, most often a global average. [That average] usually includes land and sea temperatures, which results in a lower number than land only," Gulledge added.
"It's typically annual, so you end up with both winter and summer [projections] in there. So ten degrees really sounds about right to me" for summer temperatures on land, Gulledge said.
Heated Debate
The report is sure to heat up an already boiling debate on the possible causes and likely effects of climate change.
Rapid environmental change would force all species in the region to adapt—including humans.
"Any drastic change in weather has the potential to negatively affect agricultural production in the U.S. and could seriously affect the growing season," National Farmers Union President Tom Buis said.
"We are very concerned that if these issues are not addressed to offset the impact of global warming, not only will farmers and producers be affected, but so will the consumers who rely on American crops."
Peter Stone, a climate scientist at the Massachusetts Institute of Technology, sounded a cautionary note about assumptions made on the results of single model.
"There is a wide range of possible scenarios and large differences between different models' projections for a given scenario," Stone said. "Furthermore, this particular [model] did not do well in simulating trends in summer temperatures during the test period, 1977 to 2004.
"Given all the substantial uncertainties, any objective analysis would conclude that this particular outcome has a rather low probability," Stone continued.
"It could turn out either better or worse. Any projections like this, to be truly useful, should have error bars attached to them," he added. "In this case those error bars would be very large."
The new model assumes that carbon dioxide emissions will continue to rise at their current rate: some 2 percent each year. That raises hopes that, if humans reduce greenhouse gas emissions, the extreme scenario could still be avoided.
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