SEARCH

Entries in Melting (1)

Monday
Aug272012

Arctic Sea Ice Reaches Record Low 

File photo. Jupiterimages/Thinkstock(BOULDER, Colo.) -- Arctic sea ice is melting faster than climate models projected, already shrinking to a record minimum with several more weeks of this year’s melting season, according to scientists on both sides of the Atlantic.

“The sea ice area went below the sea ice area in 2007 around Aug. 20,” said Ola Johannessen, founding director of the Nansen Environmental and Remote Sensing Center, an independent non-profit research foundation affiliated with the University of Bergen, Norway. The center conducts basic and applied environmental and climate research.

“In general, the ice area and extent has consistently decreased since 1960 and the reason is mainly the increase of CO2,” he said.

According to a report released Monday by U.S. National Snow and Ice Data Center, Arctic sea ice area has shrunk to 1.58 million square miles, breaking the previous minimum of 1.61 million square miles, set in 2007.

There will be both positive and negative effects from the record melting, Johannessen said.

On the positive side, with more water ice-free, the amount of shipping through the Northern Sea Route and the North West Passage, even directly across the Arctic Ocean, will increase.

There could also be increased oil production, since the Arctic holds 32 percent of the world’s untapped oil and gas reserves. Russia has put its first oil rig in the Arctic into operation, but it became a target of environmentalists last week when Greenpeace activists scaled it in protest.

But according to the National Snow and Ice Data Center, the loss of sea could accelerate global warming trends.

Arctic sea ice keeps the polar region cold and helps to moderate global climate. Over the past 30 years there has been a dramatic decrease in the thickness and extent of ice in the arctic.

“Melting of the Arctic is bad for climate change and fisheries,” Johannessen said.  Loss of sea ice will impact “ocean and weather patterns, and there will be increased teleconnection between high and low latitudes affecting the monsoon system in Asia and other parts of the world.”

The melt is also self-reinforcing, scientists agree. Since sea ice is white, it reflects 80 percent of the sunlight hitting it back back into space; the less of it is, the more heat the darker Arctic will absorb. Instead of reflecting 80 percent, it will absorb 90 percent of the sunlight, which will accelerate the thaw, scientists say. Several studies have found the Arctic could be ice free by 2040 or sooner.

As the Arctic melts, the ocean around it becomes warmer, leading to more loss of sea ice, and therefore a rise in sea levels.  Scientists say this sea level rise is impossible to avoid.

The Arctic Ocean has been covered with ice for more than 2.5 million years. During interglacial periods like the current one, ice melts in the summer and thaws in the winter.  Arctic sea ice reaches its maximum seasonal extent in March and shrinks through spring and summer to a minimum extent in September.

Throughout human civilization, this melting and freezing Arctic sea ice has been more or less consistent. However,what is being experienced now is unprecedented, scientists say.

Copyright 2012 ABC News Radio







ABC News Radio