Warming aids Arctic economies but far short of "cold rush"
* Oil, shipping, tourism aid Arctic as ice melts
* But thawing permafrost may mean big hidden costs
By Alister Doyle, Environment Correspondent
OSLO, Aug 28 (Reuters) - Climate change is aiding shipping, fisheries and tourism in the Arctic but the economic gains fall short of a "cold rush" for an icy region where temperatures are rising twice as fast as the world average.
A first cruise ship will travel the icy Northwest Passage north of Canada in 2016, Iceland has unilaterally set itself mackerel quotas as stocks shift north and Greenland is experimenting with crops such as tomatoes.
Yet businesses, including oil and gas companies or mining firms looking north, face risks including that permafrost will thaw and ruin ice roads, buildings and pipelines. A melt could also cause huge damage by unlocking frozen greenhouse gases.
"There are those who think that growing strawberries in Greenland and drilling for oil in the Arctic are the new economic frontiers," said Achim Steiner, head of the U.N. Environment Programme.
"I would caution against the hypothetical bonanza that some people see," he told Reuters of Arctic regions in Russia, Nordic nations, Alaska and Canada. U.N. studies say global warming will be harmful overall with heatwaves, floods and rising seas.