By Timothy Gardner
WASHINGTON (Reuters) - Global warming will likely open up coastal areas in the Arctic to development but close vast regions of the northern interior to forestry and mining by mid-century as ice and frozen soil under temporary winter roads melt, researchers said.
Higher temperatures have already led to lower summer sea ice levels in the Arctic and the melting has the potential to increase access for fishermen, tourists and oil and natural gas developers to coastal regions in coming decades.
The melting has also led to hopes that shorter Arctic shipping routes between China and Europe will open.
The Arctic is increasingly a region of deep strategic importance to the United States, Russia and China for its undiscovered resource riches and the potential for new shipping lanes. The U.S. Geological Survey says that 25 percent of the world's undiscovered oil and natural gas lies in the Arctic.
But the warming also will likely melt so-called "ice roads", the temporary winter roads developers now use to access far inland northern resources such as timber, diamonds and minerals, according to a study published on Sunday in the journal Nature Climate Change.
"It's a resource frontier where we don't even know what all is there and I'm beginning to think we never will," Lawrence Smith, a professor of geography at the University of California Los Angeles and a co-author of the study, said about the Arctic interior.
"These places are going to become wilder and the lands are going to be abandoned and revert to a wild state."
The ice roads, made famous by the History Channel show "Ice Road Truckers", are constructed on frozen ground, rivers, lakes and swampy areas using compacted snow and ice. They cost only about two to four percent of what permanent land roads would cost, making resource extraction more cost effective in these remote areas.
As the roads melt, indigenous populations could also face increased isolation and higher costs as some goods could only reach them via airplanes.
All eight countries that border the Arctic -- Canada, Finland, Greenland, Iceland, Norway, Russia, Sweden and the United States -- are expected to experience declines in winter-road land accessibility.
Russia will lose the most land suitable for winter road construction by area, followed by Canada and the United States, according to the modeling done in the study, which was supported by NASA's Cryosphere Program and the National Science Foundation.
Northern Canada's Tibbitt-Contwoyto "diamond road," an winter road first built in 1982 and said to be the world's most lucrative ice road as it services several diamond mines, is expected to be among the routes that suffer, according to the researchers. Much of the roughly 300 mile road runs atop frozen lakes.
By 2020 the road is projected to lose 17 percent of its up to 10-week operating season.
Oil and natural gas developers could lose access to some inland drilling, but the industry would gain access to coastal drilling and would benefit from easier shipping routes.
Timber and metal mining, however, would suffer far more because it would be cost-prohibitive to build permanent roads leading to these resources.
More study is needed to determine the potential economic losses from the melting regions and how they would compare to the opportunity, the authors said.
(Reporting by Timothy Gardner; Editing by David Lawder)