[00:09] The ice sheet covering Greenland is a complex and dynamic element of our climate system.

[00:14] It partially regulates Earth's temperature by reflecting sunlight back into space, and grows and shrinks in response to the temperature it helps change.

[00:24] Changes to polar ice do have consequences everywhere, not just at the poles. Melting ice results in higher sea levels that threaten coastal regions.

[00:32] Greenland's ice, which is up to two miles thick in some places, is especially sensitive to melting caused by global warming since its southern tip protrudes into warmer latitudes.

[00:43] NASA scientists compared aerial laser surveys of the southern Greenland ice sheet from 1993 to 1998 and found that the coastal ice is thinning, in some places, at a rate of more than three feet a year!

[00:56] This thinning corresponds with warmer temperatures observed in the same time period.

[01:01] How fast ice sheets will shrink and sea levels rise has major impacts for the human population, since most of the world's people live within 50 miles of a coastline.

[01:11] The melting ice in Greenland serves as a warning of how climate change in one part of the world, can impact the entire planet.

[01:19] For Our Changing Planet, I'm Jane Joyce. To learn more about Our Changing Planet, visit us on the web at www.umac.org/ocp.