VOA常速英语2007年-Scientists Unveil High-Definition Map of Antarc

A team of U.S. and British researchers have unveiled a new map of Antarctica that they say will revolutionize research on the frozen continent and contribute to a deeper understanding of climate change. VOA's Leta Hong Fincher has more.

The Landsat Image Mosaic¹ of Antarctica, or LIMA, pieces together 1,100 images to provide a new map 10 times more detailed² than any made before.

This true-color map of the full continent took eight years to compile from satellite pictures and is now freely available to the public over the Internet.

Robert Bindschadler is a chief scientist at the U.S. space agency NASA's Goddard Space Flight Center. He says, "For the vast majority of people, the way I would describe LIMA is, this is how Antarctica really looks and you can have any piece of it you want."

Bindschadler told a news conference Tuesday that the new satellite images provide a time-lapse historical record of how Antarctica has changed. The map will enable scientists to continue to watch changes unfold, such as the movement of glaciers³.

Bindschadler says researchers can use the map to better plan scientific expeditions, geologists⁴ can better trace rock formations and biologists can obtain snapshots of the levels of lakes in Antarctica's desert ecosystems⁵. "It [the map] has changed my view of Antarctica and it has influenced the science questions that I ask myself, so yes, it will revolutionize Antarctic science," he said.

Collaborators on the mapping project include the U.S. Geological Survey, the National Science Foundation and the British Antarctic Survey.

British researchers say the new images will be key to understanding climate change because Antarctica has experienced a temperature rise of almost three degrees in the last 50 years --- almost 10 times the global average. They add that more than 80 percent of glaciers on the continent are now in a state of retreat, ice shelves are breaking up, and snow is melting at a faster rate.

Nicholas Owens is director of the British Antarctic Survey. Owens says, "If society and our political leaders are to make informed decisions about how to cope with climate change, they need the most up-to-date evidence that they can possibly get, and I have absolutely no doubt that the LIMA project will contribute to that evidence."

The Landsat 7 satellite is expected to continue taking images of Antarctica and other parts of the world through 2011.