In a report on the situation in 2012, the World Meteorological Organisation said on Thursday that during the August to September melting season, the Arctic's sea ice cover was just 3.4 million square kilometres.
That was a full 18 per cent less than the previous record low set in 2007.
WMO Secretary-General Michel Jarraud dubbed it a "disturbing sign of climate change."
The WMO said that the 2012 global land and ocean surface temperature was estimated to be 0.45C above the 1961-1990 average of 14.0C.
Above-average temperatures were observed across most of the globe's land surface areas, most notably North America, southern Europe, western Russia, parts of northern Africa and southern South America, the WMO noted.