Editors note: Deborah Zabarenko, the Reuters Environment Correspondent pictured left, is reporting in Antarctica on a National Science Foundation Grant. You can read her articles here 

When you drive on a frozen sea in Antarctica, you learn to respect the weather. Even if the temperature is below the freezing mark, and there are no clouds on the horizon, and the experienced folks assure you that the ice road has been checked and rechecked by safety experts, and you know the ice is about 15 feet (4.5 meters) thick — well, sometimes you worry.

There has been beautiful spring weather this week at McMurdo Station, the coastal base for many U.S. science operations here. So an offer to ride out onto the sea ice with scientists was irresistible. We saw an Emperor penguin, a pair of Adelie penguins and seals lolling about on the ice.

But seals are not always a good sign for sea ice drivers, as the scientists knew: where there are seals on the ice, there must be a hole in the ice that the seals use to get out of the water. And much of the ice “road” flagged for use by research vehicles was messily tracked and covered with slushy pools of melted ice.

We were in a vehicle called a Mattrack, which looks like a heavy pickup truck with triangular tank-like tracks where the wheels would normally go. The driver was picking his way through the melt pools when the rear tracks broke through the surface of the ice, down about two or three feet. We were in no danger, but it was startling to realize that all of a sudden, a few miles (km) from our home base, we were not going anywhere under our own power.

The driver called for assistance, and all got back to base without mishap. One comforting note: at least there was no question that the vehicle and its passengers and driver would have to stay out after dark. The Mattrack was towed back to McMurdo Station.