Accelerated circumpolar climate change has global impact, says international scientific assessment

Brussels, 12 Oct 2004

The arctic climate is changing rapidly - more rapidly than the global average - with worldwide implications, an international gathering of science journalists was told on 5 October. A preview of the Arctic Climate Impact Assessment (ACIA) report, bringing together European and North American scientists' state of the art knowledge on climate variability, climate change and increased ultraviolet (UV) radiation, was presented to the fourth World Conference of Science Journalists in Montreal, Canada.

The most dramatic of the report's ten key findings, as laid out by one of the authors of the scientific assessment document, Professor Terry D. Prowse, Project Chief at the Canadian National Water Research Institute, is that some arctic areas are showing warming of between five and ten times the global average. Winter temperatures have risen by as much as 4°C over the last few decades, compared to a global average warming of 0.6°C.

Furthermore, the international group of scientists predicts a continued rate of warming of up to three times the global average over the next century, with winter temperatures over the Arctic Ocean rising by up to 10°C by 2100.

'There are large variations due to the albedo of snow and ice,' explained Professor Prowse, 'melting increases the areas of heat absorption due to solar radiation.'

While increased vegetation in northern regions will result in the arctic becoming a carbon sink, absorbing excess CO2, Professor Prowse warned that this will probably be outweighed by heat absorption due to the shrinking ice cover, 'More canopy will increase the absorption of radiation, and there will be a counter-balancing effect due to reduced reflectivity of the land surface,' he said.

These local or regional effects will have a global impact however, as the increase in glacial melt and river run-off will add fresh water to the ocean, disrupting the currents that transfer heat between the tropics and the poles as well as raising sea levels.

'The Arctic Ocean is surrounded by large land masses,' continued Professor Prowse, 'there has been an eight per cent increase in arctic precipitation over the last 100 years and an increase in fresh water discharge of around two cubic kilometres per year over the last 60.'

A policy document will be published following the scientific assessment, and there will be dramatic consequences for people and ecosystems due to the multiple effects of climate change and elevated levels of ultraviolet radiation.

The implications for humans are likely to be at their worst in coastal areas, with communities and facilities facing increased exposure to major storms. Alaska, Canada and Russia's Chukotka peninsular are particularly at risk. The thawing ground will disrupt transport, buildings and infrastructure around the Polar regions, and indigenous communities face major economic woes.

Arctic ecosystems will also suffer serious impact, as animal species diversity and ranges of distribution will change, and elevated UV levels will affect both plants and animals.

'The shrinking ice crust is resulting in loss of habitat and access to food for polar bears and seals, pushing some species towards extinction, while the historic migration routes of caribou and reindeer will shift,' said Professor Prowse, adding that the lowest extent of arctic tundra in 21,000 years is predicted by 2100.

There may be some surprising by-products of this gloomy forecast, as by 2080 the North-Western Passage sea route between Europe and Asia, up to 45 per cent shorter than via the Suez Canal, will be made navigable for up to 100 days of the year due to the shrinking ice cap. This is not good news however, as some models in the assessment predict a complete disappearance of the northern ice sheet by century's end.

The report, to be delivered on 9 November to the ACIA International Scientific Symposium on climate change in the Arctic in Reykjavik, Iceland, is the outcome of a four-year international project led by the International Arctic Science Committee (IASC) and the Arctic Council - an organisation that includes European and North American nations bordering the polar region, as well as representatives of indigenous peoples.

Commenting on the report's findings, Canadian MP Karen Kraft Sloan said that Canada is the 'canary in the mineshaft', acting as an early warning to the rest of the world on climate change.

More than 250 scientists and six circumpolar indigenous organisations have participated in preparing the ACIA under the leadership of the IASC, a non-governmental organisation that facilitates cooperation in arctic research in countries engaged in arctic research and in the Arctic region.

The Arctic Council is a high-level intergovernmental forum comprising Canada, Denmark, Finland, Iceland, Norway, the Russian Federation, Sweden and the USA. The arctic indigenous representatives, or Permanent Participants of the Arctic Council, are the Aleut International Association, Arctic Athabaskan Council, Gwich'in Council International, Inuit Circumpolar Conference, Saami Council, and the Russian Association of Indigenous Peoples of the North.

For further information on the ACIA report and scientific symposium, please visit:
http://www.acia.uaf.edu/pages/symposium. html

Further information on the fourth World Conference of Science Journalists can be found at:
http:///www.wcsj2004.com

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