For scientists, global warming is a disaster movie, its opening scenes set at the poles of Earth. The epic already has started. And it’s not fiction.

The scenes are playing, at the start, in slow motion: The relentless grip of the Arctic Ocean that defied man for centuries is melting away. The sea ice reaches only half as far as it did 50 years ago. In the summer of 2006, it shrank to a record low; this summer the ice pulled back even more, by an area nearly the size of Alaska.

Man-made global warming is driving up humidity levels, with the risk that rainfall patterns will shift or strengthen, tropical storms intensify and human health may suffer from heat stress, a study released on Wednesday said. ADVERTISEMENT

From 1976 to 2004, when the world’s average surface temperature rose 0.49 degrees Celsius (0.9 degrees Fahrenheit), global levels of atmospheric water vapour rose 2.2 percent, according to the paper by British scientists.

Melting Arctic sea ice has shrunk to a 29-year low, significantly below the minimum set in 2005, according to preliminary figures from the National Snow and Ice Data Center, part of the University of Colorado at Boulder. NASA scientists, who have been observing the declining Arctic sea ice cover since the earliest measurements in 1979…

Thousands of species in danger of extinction in the wild may survive only in captivity. The annual ‘Red List’ of extinct and endangered species to be published on Wednesday by the World Conservation Union is expected to show another increase in the numbers under threat of being wiped out by habitat loss, hunting, alien predators and climate change.

Last year the union warned that the world faced ‘the sixth great extinction of life on earth’ as mammals, amphibians, birds, insects, fish and plants were being lost at ‘unprecedented rates’. One in four mammals and one in eight bird species have been labelled ‘threatened’.

As global warming continues to shrink the Arctic ice, nearly two-thirds of the world’s polar bears will die by 2050, the U.S. Geological Survey said Friday.

And if global warming continues for next few years, the polar bear could soon be listed as a threatened species under the Endangered Species Act. A final decision on the bear’s designation is due in January.