CORVALLIS, Ore. A new study concludes that the future effects of global warming could be significantly changed over very small distances by local air movements in complex or mountainous terrain - perhaps doubling or even tripling the temperature increases in some situations.
In an article to be published in the International Journal of Climatology, researchers from Oregon State University used the unique historical data provided by Oregon's H.J. Andrews Experimental Forest to study potential variations in temperature caused by steep hills and valleys.
Based on a regional temperature increase of about 5 degrees projected for western Oregon by 2100, the study concluded that some locations, such as mountain ridge tops, could actually increase as much as 14 degrees at some times, while cold air pools in the valleys below them with temperature increases similar to the regional average.
"Even if the predictions for average temperature changes are accurate, there's been very little work done on what that may mean in specific locations and situations," said Chris Daly, an OSU professor of geosciences, director of OSU's PRISM Climate Group and expert on the effects of elevation and topography on localized climatic effects.
"We are finding that there's a potential here for tremendous disparities in local effects that we need to learn more about," Daly said. "Some locations may get much warmer than the average while others nearby are affected less, with associated impacts on their ecology, the plant and animals species that live there."
The steep terrain and long-term climate records in the H.J. Andrews Forest near Blue River, Ore., in the central Oregon Cascade Range, have provided an unusual data set to study this phenomenon. In general, temperatures decrease as you go up in altitude but not necessarily in the mountains. Some ridges in the H.J. Andrews are routinely warmer than protected valleys below them, especia
|Contact: Chris Daly|
Oregon State University