The four million inhabitants of the Arctic will have to change their way of life if warming trends in the region continue apace, leaders have warned.
Projected summer sea ice: 2010-2030 (top); 2040-2060 (middle); 2070-2090 (bottom)
A four-year scientific assessment of climate change in the Arctic has been published, and says the area is warming at nearly twice the global average.
The Arctic Climate Impact Assessment (ACIA) will be used by rim nations and indigenous groups to inform policy.
Circumpolar representatives say local people will have to adapt to survive.
"We are asking first for action to slow climate change," said Geir Tommy Pedersen, of the Saami Council.
"However, we realise that we will be forced to make some adaptations, as we are already seeing the effects of climate change in our communities. We need to be given the resources to deal with these challenges."
An information campaign highlighting the results of the assessment has already been started by the Arctic indigenous peoples.
"We need to tell our own people about what is in this report," said Rodion Sulyandziga, of the Russian Association of Indigenous Peoples of the North.
"They are already facing many challenges, but we must prepare them for this challenge also. More than this, we need to tell the rest of the world about the necessity of taking action on climate change, and taking it now."
The assessment was prepared by about 300 scientists for the Arctic Council, the intergovernmental forum for the eight countries which have territories in the region and six indigenous groups.
It is a review of all that is known about climate change currently in the region.
Its main findings (many highlighted in media reports over the last week) are:
The assessment's findings and projections are being presented in detail at a scientific symposium in Reykjavik, Iceland, from Tuesday.
- Average winter temperatures have increased by as much as 3-4C (4-7F) in the past 50 years in Alaska, Western Canada, and Eastern Russia. Computer models project a rise of 4-7C (7-13F) over the next 100 years.
- Current recorded and observational data show Arctic sea ice is thinning fast. Computer models project at least 50% of summer sea ice to be gone by 2100, with some simulations even showing complete disappearance by the end of the century.
- Should the Arctic Ocean become ice-free in summer, it is likely that polar bears and some seal species would be driven toward extinction.
- This would also present huge difficulties for local people who hunt food on and around the ice.
- At the same time, reduced sea ice extent is likely to increase marine access to some of the region's resources, including its oil and gas reserves.
- Agriculture will become easier in some areas as the permafrost retreats; warmer waters are likely to make some fisheries more productive.
- Warming over Greenland will lead to substantial melting of the Greenland Ice Sheet, contributing to global sea-level rise at increasing rates.
- Arctic climate changes present serious challenges to the health and food security of some indigenous peoples, challenging the survival of some cultures.
- Over the next 100 years, climate change is expected to accelerate, contributing to major physical, ecological, social, and economic changes, and the assessment has documented that many of these changes have already begun.
Its authors say its projections are based on a moderate estimate of future emissions of carbon dioxide and other greenhouse gases, and incorporate results from five major global climate models used by the Intergovernmental Panel on Climate Change.
"The impacts of global warming are affecting people now in the Arctic," says Robert Corell, chair of the ACIA.
Further warming will expand crop production in the region
"The Arctic is experiencing some of the most rapid and severe climate change on earth. The impacts of climate change on the region and the globe are projected to increase substantially in the years to come."
Once the researchers have discussed the report, political representatives from the Arctic nations - Canada, Denmark, Finland, Iceland, Norway, Russia, Sweden, and the US - and the indigenous groups will also gather to mull its findings.