Ice researchers: burning a whole lot of fossil fuel daily

If they're just now mapping the topography thousands of meters under the ice, how could anyone accurately calculate the Antarctic ice volume?

Dispatches from the bottom of the Earth: Robin Bell

AGAP SOUTH CAMP, ANTARCTICA—Weather pinned us down most of the time between Christmas and New Year's Day. Since the weather cleared, we have been trying to fly whenever we can. We are working with two teams of pilots, so on good days we can keep the plane in the air almost 22 hours. After breakfast, one team takes off on a five-hour mission, usually to the north over the top of the ice sheet toward the summit of the mountains.

When the morning team plane returns, the crew refuel the aircraft from the fuel bladders, keeping one engine turning to power the science equipment. The team then flies for another four to five hours, returning just in time for dinner. The night team begins its two flight missions right after dinner. This way, we can collect almost 4,000 km of data a day using about 1,100 gallons of fuel.
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Today the aircraft had to come home early, because the head winds were so strong; another night, the whiteout conditions made for a dicey landing. In between these moments of melodrama, we are filling in our study area line by line as the radar profiles reveal the topography beneath the ice.

With each flight, we appreciate more and more the terrain completely hidden beneath the ice. The log sheets of the scientists and engineers who operate the aircraft are sprinkled with adjectives of pointy mountains, sharp peaks, lakes and canyons. The ice beneath the camp is about 3000 m thick but, just to the north of us, the ice thins quickly to 1500 m, and the rugged terrain appears.

Unquiet Ice Speaks Volumes on Global Warming: Robin Bell

Abundant liquid water newly discovered underneath the world's great ice sheets could intensify the destabilizing effects of global warming on the sheets. Then, even without melting, the sheets may slide into the sea and raise sea level catastrophically