Arctic air temperature at record high due to sea ice loss

By Paul Eccleston
Last Updated: 4:01pm BST 17/10/2008

The continuing loss of sea ice has pushed the air temperature in the Arctic to a record high above normal, scientists have revealed.
Less summer ice - which deflects solar radiation - has resulted in a rise in both the ocean and atmospheric temperature.

The US National Oceanic and Atmospheric Administration (NOAA) says autumn air temperatures in the region are at a record 5ºC (9ºF) above average. The annual NOAA report, which monitors climate change, said there has been a near-record loss of summer sea ice, though not as much as last year which was the warmest on record for the Arctic, continuing a trend that began in the mid-1960s.
They also report a loss of surface ice in Greenland.
Increased temperatures have an impact on both land and marine creatures and are likely to result in even less ice next year, the report says.
James Overland, an oceanographer at NOAA's Pacific Marine Environmental Laboratory in Seattle and a lead author of the report, said: "Changes in the Arctic show a domino effect from multiple causes more clearly than in other regions.

"It's a sensitive system and often reflects changes in relatively fast and dramatic ways."
In 2006 the NOAA's Climate Program Office set up the Arctic Report Card as a means of monitoring changes in the Arctic atmosphere, sea ice, biology, ocean, land and Greenland.
This year three of the six areas - atmosphere, sea ice, and Greenland - are coded red indicating that the changes are strongly attributed to warming. Biology, ocean and land are coded yellow, indicating mixed signals. In 2007 there were two red areas, atmosphere and sea ice, and four coded yellow.
The report's chief editor Jackie Richter-Menge of the US Army Corps of Engineers (USACE) Cold Regions Research and Engineering Laboratory, said: "The information combines to tell a story of widespread and, in some cases, dramatic effects of an overall warming of the Arctic system."
Researchers at the National Snow and Ice Data Centre, part of the University of Colorado, reported last month that Arctic sea ice melted to its second-lowest level this summer. They said it is now 34 per cent below the long-term average from 1979 to 2000 but nine per cent above the record low set in 2007.
Professor Peter Wadhams, professor of ocean physics at Cambridge University and head of the Polar Physics Group, said the air temperature on the Arctic coastline would normally be 0ºC but this year and last year a larger area of water - where summer ice had disappeared - had led to a rise.
"This temperature anomaly has also extended 1,000 kilometres inland towards the coasts of Alaska and Siberia and is causing the permafrost to melt and methane stored in it to leak," he said.
"The warmer temperatures will also take longer to dissipate, the autumn freeze will take longer, meaning thinner ice. There is always a fluctuation in the thickness of the ice year on year and the loss this year wasn't as extreme as last year - but it was almost.
"We have got to a tipping point where the breakdown of ice will lead to it disappearing altogether in the summer."
Prof Wadhams said changes brought by a warmer climate were happening across the globe at all latitudes but could be most clearly seen in the Arctic.
"Satellite pictures clearly show the open water where ice used to be. It is the most obvious example of climate change in action which is changing the appearance of the planet," he said.