NASA - National Aeronautics and Space Administration

If you put ice into a bowl and then pour warm water onto the ice, the ice cubes melt away quickly. That's what a scientist at NASA claims is happening as warm waters make their way into the frigid waters of the north and south poles where there’s lots of ice.

Image to right: Photo of Dr. Bob Bindschadler on an expedition. Credit: NASA

Warm waters are now reaching glaciers and ice sheets around the world. Now, the pieces to a years-old scientific puzzle have come together to confirm warmer water temperatures are creeping into the Earth's colder areas. Those warm waters are increasing melting in polar areas. No reversal of this warm water is in sight.

Dr. Robert Bindschadler, a glaciologist at NASA's Goddard Space Flight Center in Greenbelt, Md. wrote an article on this observation that was published in the March 24 issue of Science magazine.

For many years, ships and ocean buoys took the temperature of the ocean's surface. They've shown that all of the oceans began warming before satellites could see them. Most of the warming was limited to the upper six-tenths of a mile, except in the North Atlantic. In the cold waters of that region, heat went even deeper into the ocean. This warming has increased the melting of sea ice in the North Atlantic.

These warm waters are also beginning to melt the underside of the floating fringes of the Greenland ice sheet, even at great depths. It is these fringes that have been holding back large amounts of ice locked up in the Greenland ice sheet, and as this ice has been melting, the glaciers have quickened their flow to the sea.

Image to left: Jakobshavn Glacier Retreat 2001-2003: Jakobshavn Isbrae holds the record as Greenland's fastest moving glacier and major contributor to the mass balance of the continental ice sheet. Starting in late 2000, following a period of slowing down in the mid 1990s, the glacier showed significant acceleration and nearly doubled its discharge of ice. The following image from the Landsat satellite shows the retreat of Jakobshavn's calving front from 2001 to 2003. Credit: NASA

Mankind has usually known glaciers to move very slowly. Sayings like "You move as slow as a glacier" or "you're moving at a glacial pace" are common. Recently, however, scientists determined that over the last several years, three glaciers in Greenland have been moving more than twice as fast as they used to. Since 1997, one glacier called Jakobshavns has been moving at 49 feet per year since 1997. Two others have been moving at 131 feet and 82 feet per year.

This isn’t just happening in Greenland, however, scientists are seeing similar behavior in Antarctica as well.

"Because glaciers around both major ice sheets are [speeding up] and thinning means warm water has reached them," Bindschadler said. "I see no process to reverse this and expect increased ice sheet [melt] to continue and probably to spread with the result being further raising of sea level."

In an effort to understand these changes, NASA continues to monitor sea surface temperatures and the behavior of glaciers and ice sheets around the world.

Related Links:

+ Tour of the Cryosphere site
+ Media advisory info
+ Related images and video

 

 

Rob Gutro
Goddard Space Flight Center