By 2091, the north will have seasons, temperatures and possibly vegetation comparable to those found today 20 to 25 degrees of latitude further south, said Ranga Myneni of the Department of Earth and Environment, Boston University.

Canada, Northern Eurasia and the Arctic are warming faster than elsewhere as a result of the loss of snow and ice, he said. In 90 years, Alaska or Canada's Baffin Island in the Arctic may have seasons and temperatures comparable to those in today's Oregon and southern Ontario. Summer 2012's record melt of sea ice was 80 percent greater when compared to summers 30 or more years ago. This winter, most of the ice in the Arctic is thin, first-year ice that is more easily fractured and likely to melt quickly when the summer comes.

The ramifications of this planetary-scale change are just beginning to be understood.