Monday, June 14, 2010

Climate change in Arctic - Quick facts

In the last three decades, the Arctic ice has shrunk by about 10% a decade, which is around 28,000 square miles each year.

Polar bears are particularly vulnerable to climate change, and the loss of Arctic's ice. Polar bears have experinced significant decline in population in the last couple of years, and some scientists estimate that if current trend continues polar bears will become extinct before the end of this century.

Due to ever-increasing climate change impact many unique Arctic habitats for flora and fauna are disappearing. For instance we can already see tundra ecosystems being replaced by species typical of more southern locations, such as evergreen shrubs in some locations due to warmer temperatures. Some studies have even showed that the Arctic region was getting darker and absorbing more heat in the summer because of a significant shift in plant growth from grasses and lichen to larger shrubs over the past 30 years due to warmer temperatures.

Some recent studies have confirmed that surface temperatures over much of the Arctic landscape, have jumped six to 10 degrees C above normal in recent years, especially in summer months. One of the main reasons for this is the loss of reflective, white sea ice which causes more solar radiation to be absorbed by the dark water, heating surface layers further.

Additional reason to worry is the fact that the accelerated warming of the Arctic area will soon release more greenhouse gases from the Arctic that were previously locked in permanently frozen ground.

Arctic ice is not getting enough time to thicken because accelerated warming causes the surface water to get warmer, which delays the onset of freeze up in the winter and leads to a shorter period of ice growth.

Many studies have so far confirmed that nearly all Arctic's glaciers are decreasing in mass, resulting in rising sea levels.

In summer of 2008, for the first time in recorded history, both the north-west and north-east passages were ice-free.

The worst ice decline at Arctic was in the summer of 2007 when ice covered only 4.4m square kilometres.

No comments:

Post a Comment