Record-breaking temperatures 'have robbed the Arctic of its winter'

Fort Yukon has recorded Alaska's coldest ever temperatures but this winter temperatures have been much warmer than usual, leading to dangerously thin ice

This year's record-breaking temperatures have robbed the Arctic of its winter, sending snowmobilers plunging through thin ice into freezing rivers and forcing deliveries of snow to the starting line of Alaska's legendary Iditarod dogsledding race.

Last month's high temperatures - up to 16C (29F) above normal in some parts of the Arctic - flummoxed scientists, and are redefining life in the Arctic, especially for the indigenous people who live close to the land.