An Ice-Free Arctic Ocean?

Arctic sea ice is melting at a record rate, according to figures released by the National Snow & Ice Data Center in Colorado Springs. On August 13, 2012, the extent of sea ice in the Arctic Ocean had fallen 2.69 square kilometers (1.97 million square miles) below the 1979-2000 average for the same date, and 483,000 sq. km (186,000 sq. mi) below the same date in 2007, the previous record low year. The data was supplied by the European Space Agency’s radar-equipped satellite Cryoset, launched in 2010 to monitor changes in the thickness of arctic sea ice.  Measurements from overflying aircraft and sonar buoys confirm the Cryoset figures.

With two weeks still to go in the arctic melt season, NASA scientists believe that arctic sea ice will drop to its lowest point ever recorded. Computer models developed by scientists at NASA’s Goddard Space Flight Center project an ice-free Arctic Ocean during the summer months by 2035. According to the model, Arctic ice will become seasonal, allowing ships to sail the fabled Northwest Passage “over the top of the world” for a good part of the year. Some Chinese container ships have already started using the shortened route to ship goods directly to Europe and U.S. East Coast ports.

Not only are the boundaries of the Arctic ice cap shrinking, but the ice is thinning in some areas. In the past decade alone, sea ice thickness north of Greenland has fallen 65%, from 5 to 6 meters (16 to 20 ft) to 2 meters (6.6 feet).

As the Arctic ice melts faster, and the fall freeze continues to start later, there will be less ice to reflect the sun’s rays back into space, which allows the sun to heat the Arctic Ocean water. A warmer Arctic Ocean will contribute to sea level rise and warmer oceans worldwide, and overall global warming. Aquatic  wildlife species that depend on sea ice and colder water will disappear. Humans will have to adjust to rising ocean levels around the world, plus a warmer climate  with longer, hotter droughts and more destructive floods and storms.