Manhattan-sized ice island heads out to sea

Remember that enormous slab of ice that broke off Greenland's Petermann Glacier back in July? It's now on its way out to sea, a little bit smaller than it was a couple of months ago—but not much. At around 10 miles long and 4.6 miles across (16.25 x 7.5 km) this ice island is actually a bit shorter than Manhattan, but is fully twice as wide.

The image above was acquired on September 14 by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA's Terra satellite.

Although the calving of this particular ice island isn't thought to be a direct result of increasing global temperatures, climate change is thought to be a major factor in this year's drop in Arctic sea ice extent, which is now below 4.00 million square kilometers (1.54 million square miles). Compared to September conditions in the 1980s and 1990s, this represents a 45% reduction in the area of the Arctic covered by sea ice.

This year sea ice in the Arctic Ocean dropped below the previous all-time record, set in 2007. 2012 also marks the first time that there has been less than 4 million square kilometers (1.54 million square miles) of sea ice since satellite observations began in 1979.