An international science team unveiled a new high-definition, interactive map of Antarctica on Tuesday, capping an eight-year satellite mapping project.
The Landsat Image Mosaic of Antarctica, or LIMA, is the most geographically accurate depiction of the full continent ever made — and it’s being made freely available over the Web.
Researchers can use the true-color map to plot their expeditions, geologists can get a better fix on remote rock formations, and the general public can get its best view yet of a continent that looms large in the imagination as well as real-world climate science.
"This innovation is like watching high-definition TV in living color versus watching the picture on a grainy black-and-white television," Robert Bindschadler, chief scientist for the Hydrospheric and Biospheric Sciences at NASA's Goddard Space Flight Center in Maryland, said in the space agency's announcement of the project.
During a Goddard news briefing on Tuesday, Bindschadler went even further, comparing the 100-billion-pixel database to a shiny new Ferrari he's finally able to take out on the road.
"I have had an absolute ball looking at this data set," he said.
Bindschadler conceived the project and initiated NASA's collection of Antarctic images from the Landsat 7 satellite in 1999. In all, about 10,000 images — most of them taken between 1999 and 2001 — were analyzed to come up with a mosaic of 1,100 images that present a cloudless, seamless view of the continent.
NASA's partners in the effort include the U.S. Geological Survey and the National Science Foundation, as well as the British Antarctic Survey.
"Although vast and inhospitable, the Antarctic is the world's most powerful natural laboratory," Nicholas Owens, director of the British Antarctic Survey, said in a video statement. "But no one nation can possibly hope to understand and study the vastness of Antarctica, which is why it is important to work together in international collaboration."
The data set is being presented as the "first major benchmark data set" marking the International Polar Year, a scientific campaign focusing on the polar regions in 2007-2008, Bindschadler told reporters. "It was exactly this type of project the IPY visionaries had in mind," he said.
The Landsat imagery covers 80 percent of the Antarctic continent, a land mass that is bigger than the contiguous United States and Mexico combined, said Scott Borg, director of Antarctic sciences at NSF. The area around the pole can't be seen by Landsat 7 because of the satellite's orbit and camera configuration, but that gap has been filled in with lower-resolution imagery from other satellites.
The resolution of the LIMA imagery is 10 times better than any other continent-wide database for Antarctica — good enough to spot features half the size of a basketball court, NASA said. Borg said polar researchers can use the data to get recent snapshots of the continent's otherworldly ecosystems and compare them with future data sets.
Two Web sites for the public
But LIMA isn't just for scientists: "Anyone with a Web connection can now travel to Antarctica in the virtual sense," Bindschadler said.
Two Web sites have been set up to make the imagery available:
- provides a zoomable, searchable viewer to see the satellite pictures from Landsat as well as from Canada's Radarsat, a satellite that captures radar imagery of the same terrain. Different filters can be used to highlight subtle variations in color — a feature Bindschadler called the "sunglasses stretch."
- focuses on user-friendly education and outreach. The Web site puts Antarctic imagery in a scientific context and presents interactive extras such as "Antarctic Mysteries," a quiz that invites users to identify odd-looking features from the LIMA database. A search tool links the NASA site to the USGS Web site.
Borg said NSF contributed almost a million dollars to help make the data accessible over the Web, and future imagery will likely be incorporated into the database to provide a record of change over time. That's an important consideration for Antarctica, where some regions have experienced significantly more warming in the past 50 years than the global average.
"The climate of our world is changing nowhere faster than in the Antarctic," Bindschadler said.
Landsat 7 is due to continue capturing imagery of Antarctica and other parts of the world through 2011, when NASA is due to launch its successor, the Landsat Data Continuity Mission. Ray Byrnes, liaison for satellite missions at USGS, said his agency would work with NASA not only to get the next Landsat effort off the ground, but to get the imagery into the LIMA database as well.
"NASA and USGS will do everything they can to make sure the data will be there for that purpose," Byrnes said.