United Nations warns that melting permafrost may accelerate global warming.

Scientists from the United Nations Environment Programme (UNEP) warned on 7 February that carbon stored in the permafrost of Arctic lands, which accounts for an estimated 14% of the world’s total carbon, is starting to be released as rising temperatures cause the permafrost to melt and its organic material to be broken down by bacteria.

The revelation was made at a meeting of the United Nations Governing Council in Nairobi, Kenya, by Svein Tveitdal, managing director of GRID Arendal in Norway, a UNEP environmental information centre monitoring the melting of the permafrost. “Permafrost has acted as a carbon sink, locking away carbon and other greenhouse gases like methane, for thousands of years. But there is now evidence that this is no longer the case, and the permafrost in some areas is starting to give back its carbon. This could accelerate the greenhouse effect, ” Tveitdal said.

He said there were already impacts on roads, buildings, pipelines and other infrastructure occurring in Arctic areas like Alaska and Siberia as result of “the recent decades of climate change”. Permafrost, which is a solid structure of frozen soil, can be an ideal terrain on which to build; but rising temperatures can turn it into a soft, slurry-like, material which can trigger subsidence and damage to buildings and structures.

Studies by the University of Alaska at Fairbanks indicate that a change in permafrost temperature of minus four degrees Centigrade to minus one degree Centigrade decreases the load capacity of permafrost by as much as 70%. In some parts of Siberia, homes and buildings are already suffering as a result with cracks and other fractures appearing. UNEP scientists also fear the melting of the permafrost may also have important impacts on wildlife and the traditional lifestyle of indigenous people living in the Arctic – an estimated 200,000 indigenous people are represented in Arctic Russia alone.

Dr Tveitdal, whose organisation is UNEP’s key Arctic centre, said it was urgent for governments to act to reduce the threat of climate change on the Arctic by implementing the targets of a five per cent cut back in greenhouse gases, agreed to in Kyoto in 1997, as a first step. In September last year, an international conference of ministers attempting to develop rules for the 1997 Kyoto Protocol on climate change ended without success (see related story), and the new US administration has postponed further talks.

“The political response at the moment is far slower than the estimated rate of climate change this century,” Tveitdal said. “Even with the Kyoto targets, we are far away from reducing emissions by the 60% to 70% researchers suggest is necessary to stabilise greenhouse gas concentrations in the atmosphere”.

Tveitdal said the recent report of the Intergovernmental Panel on Climate Change estimating that temperatures this century may rise by up to 5.8°C (see related story), had added new urgency. “In some areas like the Arctic you might have up to 10°C this century,” he added.

UNEP says that it is inevitable that countries in the Arctic will have to therefore adapt to the impacts of global warming and crucial to this will be good monitoring of the way the permafrost is responding to rising temperatures. Therefore GRID Arendal have produced interactive maps, illustrating the current extent of permafrost in blue, which will act as a baseline from which scientists and policy makers can track the melting and shrinking of the frozen soils.

“I do not think it is radical to say that the map will become progressively less blue in the coming years,” Tveitdal said. The threat of climate change to the Arctic and its permafrost will take centre stage at the Arctic Council meeting of ministers taking place in Finland in June.