Arctic Warming
Dramatic Shrinkage of the Arctic Ice Cover

As global warming marches on and its effects unfold, the shrinkage of the Arctic ice cover that has been observed by the beginning of the 21st century may possibly be called a “poster case” for global warming.

Arctic Warming
Alaskan Ice Melting
Photo: Flickr.com

This particular region is not only a passive recipient of the global warming phenomenon with all its effects following, it is also an active agent in bringing about further global changes as a direct result (feedback) of the warming effects it is experiencing now.

In other words, it is both a result and a cause of global warming.

The Arctic Climate Impact Assessment prepared by the Arctic Council and released in 2004 gives an excellent overview of the current state of the Arctic region from the point of view of climate change.

All the information provided below is based on the findings of this report. (22)

Here is some evidence that Arctic warming is real, i.e. that global warming is indeed affecting the Arctic region:

• In the past few decades the Arctic average temperature increased at twice the rate as the rest of the world

• Declining snow cover; widespread melting of glaciers and sea ice

• Rising river flows: river discharge to the ocean has increased and spring peak river flows are now occurring earlier

• Increased precipitation much of which comes in the form of rain, with the largest increases in autumn and winter

• Rising permafrost temperature leads to permafrost thawing

Some of the current and potential future effects of Arctic warming and its shrinkage:

• Removal of the highly reflective Arctic ice cover reduces the albedo of the Earth – the ability of the planet to reflect a certain quantity of solar energy back to space. This leads to the Earth absorbing more sunlight and further contributes to climate warming.

This is exactly when the Artic ice melt becomes a cause of global warming.

• Global and regional sea level has risen by 10 – 20 centimeters during the last century, as a result of the warming process. This will affect the ocean circulation patterns and, consequently, global and regional climate

• Arctic climate change will have an impact on global biodiversity because some migratory species rely on the Arctic grounds for breeding and feeding

• Forests will replace a significant proportion of existing tundra, and tundra vegetation will move into polar deserts. The larger tree cover is expected to increase carbon removal from the atmosphere, though the reduced reflectivity of the surface will most likely outweigh this effect.

Global warming is expected to increase forest fires and destruction of trees by insects. This will lead to the loss of valuable biodiversity-rich old-growth forests.

• Reduction in sea ice will have a devastating effect on polar bears, ice-dependent seals and local people who use these animals as a food source

• Reduced sea ice will allow for extraction and shipping of oil which will further damage the marine habitat and negatively affect the health of local populations

• Many coastal communities face exposure to storms because rising sea level and a reduction in sea ice will allow high waves and storm surges to reach the shore; these storms in their turn will lead to coastal erosion

• Indigenous communities face major economic and cultural impacts whose lifestyles are closely linked to the health of their ecosystems

It is becoming more obvious that changes to the Arctic system are happening much faster than predicted even several years ago.

The WWF 2008 update report on the Arctic climate change makes a reference to ”the recent severely accelerated melting of both the Greenland Ice Sheet and the Arctic sea ice.” (23)

For example, the extent of Arctic sea ice was the lowest on record in September 2007. During this period, the extent of sea ice was 39% less than its 1979 – 2000 mean. The main reason for this is believed to be climate warming which reduced both the area and thickness of multi-year ice and made the remaining ice more vulnerable to summer thaw. (24)

The melting of the Greenland Ice Sheet would have a particularly significant effect on global sea level. If this entire ice sheet melted, it would raise the sea level by 7.3 meters, with destructive effects all over the planet. (25)

It is pretty clear that the real solution to the Arctic shrinkage problem lies in solving the issue of global warming as such.

The sooner we sort it out, the better – the time is certainly running out fast.

Last Update: November 2008