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IPCC Report - The Arctic: Thawing Permafrost, Melting Sea Ice And More Significant ChangesScience Daily — Dramatic changes to the lives and livelihoods of Arctic-living communities are being forecast unless urgent action is taken to reduce greenhouse gases, according to the Intergovernmental Panel on Climate Change (IPCC). Declines in sea ice are likely to open up the Arctic to more shipping, oil and gas exploration and fisheries. (Credit: Canadian Ice Service / Environment Canada) Its Working Group II predicts wide-ranging thawing of the Arctic permafrost which is likely to have significant implications for infrastructure including houses, buildings, roads, railways and pipelines. A combination of reduced sea ice, thawing permafrost and storm surges also threatens erosion of Arctic coastlines with impacts on coastal communities, culturally important sites and industrial facilities. One study suggests that a three degree C increase in average summer air temperatures could increase erosion rates in the eastern Siberia Arctic by three to five metres a year. In some part of the Arctic, toxic and radioactive materials are stored and contained in frozen ground. Thawing may release these substances in the local and wider environment with risks to humans and wildlife alongside significant clean up costs. Warmer temperatures also represent new economic opportunities but also challenges in the Arctic. Declines in sea ice are likely to open up the Arctic to more shipping, oil and gas exploration and fisheries. A comprehensive sustainable development plan is urgently needed for the region to maximize the opportunities and minimize potentially damaging impacts. The future health and well being of Arctic peoples is a major question. The report, part of the IPCC’s fourth assessment, recognizes that Arctic communities and indigenous peoples lives and livelihoods are intimately linked with their environment but that this is already changing. Inuit hunters are now navigating new travel routes in order to try to avoid areas of decreasing ice stability that is making them less safe. In the future, increased rainfall may trigger additional hazards such as avalanches and rock falls. Inuit hunters are also changing their hunting times to coincide with shifts in the migration times and migration routes of caribou, geese as well as new species moving northwards. Some impacts of climate change may improve human well-being. Opportunities for agriculture and forestry may increase. There is evidence that Arctic warming could reduce the level of winter mortality as a result of falls in cardiovascular and respiratory deaths. But this will have to be set against possible increases in drought in some areas, the emergence and survival of new pests and diseases, likely contamination of freshwaters and health and psychological impacts of the loss of traditional social and ‘kinship’ structures. However, it is likely that in order for Arctic communities and cultures to survive and conserve their centuries-old ways of life decisive emissions reductions will be needed alongside adaptation to the climate change already underway. Achim Steiner, Executive Director of the UN Environment Programme (UNEP), said: “The costs of climate change are already being paid by the peoples and communities of the Arctic. The report underlines how this bill is set to rise unless action is taken to cut greenhouse gas emissions”. “The communities and Indigenous peoples of this region are skilled in adapting to harsh and often dramatic changing conditions including sharp fluctuations in the scarcity and in the abundance of land and marine resources. However, the rapid changes likely in the future may overwhelm traditional coping strategies. It is thus also vital that communities are assisted in climate proofing centuries-old lifestyles in order to survive and to thrive through the 21st century,” he added. Permafrost By the mid-21st century, the area of permafrost in the northern hemisphere is expected to decline by around 20 per cent to 35 per cent. The depth of thawing is likely to increase by 30 per cent to a half of its current depth by 2080. Permafrost thawing is already having impacts. It is the likely cause behind the draining away and disappearance of Arctic lakes in Siberia during the past three decades over an area of 500,000 square km. The costs of relocating subsiding towns and villages could be high. The price tag for relocating a village like Kivalina in Alaska has been estimated to be $54 million. Marine Resources Changes in river flows, ice regimes and the mobilization of sediments as a result of permafrost thawing are likely to have impacts on freshwater, estuary-living and marine biodiversity upon which local and indigenous people depend. Lake trout, a cold water fish, is likely to be affected as will be the spawning grounds of fish and bottom living life forms as a result of increased sediments. Important northern fish species, like broad whitefish, Arctic char, Arctic grayling and Arctic cisco are likely to decline as a result of changes in habitats and predatory species, perhaps carrying new diseases, moving into the warming Arctic waters. Thinning and reduced coverage of sea ice is likely to have important knock on effects. Crustaceans, adapted for life at the sea ice edge, are an important food for seals and polar cod. Narwhal also depend on sea-ice organisms. “Early melting of sea ice may lead to an increasing mismatch in the timing of these sea-ice organisms and secondary production that severely affects populations of the sea mammals,” says the IPCC report. However more open water and other climate-related factors are likely to benefit fish stocks like cod, herring, walleye and Pollock. Forests Ten per cent and possibly as much as 50 per cent of the Arctic tundra could be replaced by forests by 2100. The narrow, remaining coastal tundra strips in Russia’s European Arctic are likely to disappear. Meanwhile climate change is likely to favour pests, parasites and diseases such as musk ox lung worm and nematodes in reindeer. Forest fires and tree-killing insects such as spruce bark beetle are likely to increase. Note: This story has been adapted from a news release issued by United Nations Environment Programme. New! Search Science Daily or the entire web with Google: |
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