北极圈坚冰融化

For thousands of years, the Arctic was an unrelenting impenetrable wilderness covered by thick ice all year round. But the melting polar caps mean man can now access what's been called "the last frontier" for several months a year. And that has energy companies and countries salivating at the prospect of the riches that lie beneath the region's ice-cold waters. It is perhaps the last great unexplored source of oil and gas on earth. But there're huge risks involved not least the harsh weather, there's also the potentially catastrophic damage an oil spill could have on the fragile ecosystem. Tourism companies are also eyeing the Arctic as a big destination for thrill seekers. Matthew Swan is one of the first to get there. His firm Adventure Canada has been organising cruises in the Arctic for 25 years. So who better to tell us how the environment has altered in the time since he's been operating there?

"This is a part of the world where ice is life. Repeatedly now in the last, I'd say, three, four years, in particular, we're getting reports from Inuit, hunters especially living in small Greenland and Arctic Canadian communities who are reporting that they now are going out as much as a month later onto the ice to hunt in the winter, and that season is ending a month earlier. So you're talking about 60-day reduction, I would say even in the last five years, that's pretty significant."