Antarctic Sea Ice

Sunday, October 7th 2007, 6:17 pm
By: News On 6

A News Tip from NASA ...


This week an international team of scientists is braving frigid temperatures on an Australian ship in the sea ice around the Earth’s coldest and least understood continent in search of answers to a key scientific question: How well do estimates of sea ice thickness captured from a NASA satellite reflect reality in the Antarctic?

In a first-ever project, scientists are planning to combine satellite laser measurements of Antarctic sea ice thickness with helicopter-based laser observations and on-the-ice measurements. Changes in Antarctic sea ice thickness could have a major impact on both the global climate system and the ocean ecosystem. Sea ice acts as a boundary between relatively warmer ocean waters and the colder atmosphere.

On Oct. 2, NASA switched on the Geoscience Laser Altimeter System aboard its ICESat satellite one month ahead of schedule, according to ICESat project scientist Jay Zwally who is leading the analysis of the ICESat sea ice data.
This was designed to coincide with a major Antarctic sea ice field campaign, the Sea Ice Physics and Ecosystem Experiment, now underway aboard the research vessel Aurora Australis. One major objective of the campaign is to investigate the thickness of sea ice and snow cover in the region off the Antarctic coast between 115° and 130°E, over which ICESat orbited Oct. 4 and 5.

Thorsten Markus of NASA’s Goddard Space Flight Center, Greenbelt, Md., and 45 other scientists from eight countries are now in the Antarctic carrying out experiments beneath the satellite’s orbit while the ship travels through the sea ice zone. A helicopter from the ship will use several instruments to measure sea ice elevation and the thickness of snow covering the sea ice as researchers make measurements on the surface of the ice floes.

The Sea Ice Physics and Ecosystem Experiment is organized by the Antarctic Climate and Ecosystems Cooperative Research Center and the Australian Antarctic Division with NASA participation. It is among over 200 multinational International Polar Year research projects. To learn more about the SIPEX field campaign, visit:

To learn more about ICESat, visit: