Editor's note: Marine geophysicist Robin Bell is leading an expedition to Antarctica to explore a mysterious mountain range beneath the ice sheet. Following is the 20th of her updates on the effort as part of ScientificAmerican.com's In-Depth Report on the "Future of the Poles."

The entire camp let out a sigh when the last survey flight landed.  Together we had sent the plane t on 52 missions, a distance equivalent to flying twice around the globe.  The survey data now fills two large aluminum boxes that will be shipped back to the U.S. separately. Our focus quickly turned from collecting the data to packing and preparing to head north. No C-130s had landed at the camp in almost a week.  Two had flown overhead only to return to McMurdo without touching down, so there there was much angst over when a flight might arrive.  The carpenters, who had been waiting to get out, had almost come to blows over words in Scrabble.  The temperatures were dropping with the wind chill now routinely hovering below –40 degrees, which ScientificAmerican.com readers will know, is the same in Fahrenheit as it is in Celsius, and it is cold no matter what system you use. It was time to pull out and head home.

The sun had not yet set in Antarctica,.  The sunset at the South Pole will not be until March.  At the AGAP Camp, located at -84 degrees south, each day the sun would spin around in the sky.  It would be lowest just after our breakfast. As the season progressed, the sun dipped closer and closer to the horizon, hinting at the long night to come.  At home in the northern hemisphere, the sun  climbs higher in the sky each day and the sunset comes a minute later as the day lengthens.  The temperature was close to –50 degrees Celsius (–58 Fahrenheit) when the camp was opened and no one wants to be around when it plunges that low again.  

Waiting for a flight in Antarctica makes any delay in a normal airport seem short.  We finished our survey on a Saturday, but the C-130 didn't arrive until the middle of Tuesday night, because of bad weather, mechanical problems and other delays. Much to our dismay, a fog bank had rolled in from the southwest and the visibility was terrible.  We could not see the big aircraft as it passed over the camp. It looked unlikely that we would be flying out.

The word we received was that the pilot would fly by once more, so all eyes were  turned skyward when the fog-shrouded C-130 Skier landed. The New York Air Guard delivered 3,000 gallons of fuel so the camp will be able to start up quickly next year when the temperatures are once again a bone-chilling –50 degrees C. Next, it was time to drag the 2,600-pound pallet of science gear over the snow to the aircraft.  Finally, the 20 passengers walked around the nose of the aircraft and entered through the forward crew door. 

Strapped down on the red webbing seats, we braced for the takeoff.  The fog means no wind.  No wind means a slow takeoff.  Wallowing down the skyway, it seemed as if we would never be airborne.  Just before the flags that mark the end of the runway, the rear skies left the snow and we were northbound!

Everyone was used to the cold, but this flight had everyone  bundled in parkas trying to stay warm.  This first three hours  in the air over the East Antarctic Ice Sheet would make the remaining 26 hours of air travel seem comfortable.  When we landed in McMurdo, we all peered out the window: the brown hills seemed foreign, as did the bird that flew past.  We had seen nothing but flat white for over a month and no wildlife other than our human companions.

It is only five days later, and rather than skiing on three kilometers of ice at the camps, I am  skiing (cross country) on three inches of ice on the reservoir near my house.  The zero-degree C (32-degree F)  temperatures seem so warm and the sun sets and rises each day! We scare up a bald eagle on our dawn ski.  As this bird flies to the east toward the edge of the Hudson, I close my eyes and picture the Gambrutsev Mountains.  How long has it been since a bird landed on those peaks? The data  enroute  to us now will help us unravel the history and mysteries  of these mountains, rivers and lakes. 

Photo by Robin Bell at AGAP SOUTH CAMP, ANTARCTICA as the team was preparing to pull out