NASA completes high-res map of Antarctica

The Fimbul Ice Sheet is highlighted in this image of Antarctica rendered from Radarsat data

October 19, 1999
Web posted at: 3:10 p.m. EDT (1910 GMT)

(CNN) -- It is the coldest and highest of continents, with a land mass larger than Europe. But Antarctica is also the least explored and least understood continent on Earth.

For 18 days during the Southern Hemisphere spring of 1997, a NASA-launched Canadian satellite called Radarsat collected pieces of a puzzle that will help scientists study this remote and inaccessible continent. Scientists announced this week that they now have the pieces put together, forming the first high-resolution radar map of the mysterious frozen continent.

With detail to the point of picking out a research bungalow on an iceberg, the new map has both answered scientists' questions about the icy continent and left them scratching their heads about what to make of strange and fascinating features never seen before.

	RADARSAT IMAGE GALLERY
Take a virtual tour of Antarctica

"This map is truly a new window on the Antarctic continent, providing new beginnings in our Earth science studies there," said Dr. Ghassem Asrar, NASA associate administrator for Earth Science. The new map was produced as part of NASA's Antarctic Mapping Project.

The most amazing features scientists now see are twisted patterns of ice draining from the ice sheet into the ocean, NASA said in a statement.

"We were surprised to see a complex network of ice streams reaching deep into the heart of East Antarctica," said Kenneth Jezek, a glaciologist from the Byrd Polar Research Center at Ohio State University.

Ice streams are vast rivers of ice that flow up to 100 times faster than the ice they channel through, with speeds up to 3,000 feet per year. "There are some extraordinary ice streams in East Antarctica that extend almost 500 miles -- nearly the distance along the Mississippi River from New Orleans to Cairo, Illinois," Jezek said.

Antarctica looks pure, white and mostly featureless to the low-resolution satellites that previously mapped the frozen landscape. But with the new Radarsat map, the continent comes alive. Blocks of broken sea ice line the coast and sedimentary rock protrudes from the rocky walls of Antarctica's Dry Valleys; the vast, perplexing Antarctic Ice Sheet flows and twists into the sea; volcanoes poke through the ice sheet and ice streams flow like rivers into the Southern Ocean.

Even the tracks of wayward snow tractors on their way to inland stations are visible. "We have a new view of the entire southern continent. It shows us something about an extraordinary part of our world and how humans may be changing it -- on both local and global scales," Jezek said.

NASA's study of the Antarctic is part of the Agency's Earth Science Enterprise, a dedicated effort to better understand how natural and human-induced changes affect the Earth's environmental system.