Environmentalists bemoan the disastrous effects that global warming could have on habitats for Arctic wildlife and indigenous peoples, citing estimates that the Arctic could be ice-free in the summertime by 2080. But not all those who foresee an Arctic melt are doomsayers. A handful of ship owners see a pot of gold at the end of that rainbow, or in this case, the end of the Arctic passage. “In the next 1O years, I believe we will solve the problems of round-the-year goods transport via the Northern Sea route,” said Alexander Medvedev of Russia's Murmansk Shipping Company. 　Murmansk Shipping currently runs two or three cargo voyages per year from Japan to Europe, using icebreakers to plow through this new route, which hugs the coast of northern Russia. Medvedev believes that with the predicted melt, up to 15 days could be shaved off the voyage from Europe to Japan and back, particularly in the summer. The shrinking ice could therefore expand the company's shipping opportunities exponentially.   The passage through the other side of the Arctic, the Northwest Passage, which snakes ever Alaska and through a maze of islands off Canada, will likely be clogged with ice for another two decades beyond the opening of the Northern Sea route above Russia. The Northwest Passage is further north than the Russian route, and it passes through straits more easily blocked by ice. But most scientists agree that while the specifics are open to question, both passages will be open within this century.  　For environmentalists, the new passages portend a potentially disastrous get-rich rush to northern resources, “Melting of the ice will make access far easier to northern Siberia and other wilderness regions,” states Svein Tveitdal of the U.N. Environmental Program's polar center. “There has to be a strategy for sustainable development of the Arctic. It mustn't be a sort of new Africa, where colonists exploited the resources.”   While shipping companies may face less ice in the future, they still must contend with other obstacles. Aware of ice-instigated disasters like the Titanic, insurance companies are hesitant to cover Arctic shippers. resulting in pricey premiums. In addition, shippers must equip their ships with ice-resistant hulls und provide icebreaker escorts, which could wipe out the financial advantages of shorter routes. As the ice recedes, movements also face billions of dollars in expenses to make the passages usable. Ports in northern Russia, for instance, have been left to deteriorate since the end of the Cold War, which nuclear-powered icebreakers regularly led warships between the Pacific and the Atlantic. “The obstacles are more economic and political,” said Peter Wadhams of Cambridge University. “It is a question of infrastructure: navigational aids, search and rescue teams, the ability to clean up pollution.”   At least one scientist, however, thinks the predictions themselves are premature. According to Rob Huebert of Canada's Centre for Military and Strategic Studies, global warming is having an inconsistent effect in Arctic regions. “In some areas the ice is getting thicker,” said Huebert, “even as it breaks up elsewhere.” These areas, as if to snow on the global-warming parade, are doing the unthinkable: getting colder.