Copenhagen correspondent Gelu Sulugiuc and Reuters photographer Bob Strong ventured to Greenland to visit a team of scientists studying the melting of the ice sheet. The following was written at Swiss Camp, on the ice cap.

After a bumpy 35-kilometre snowmobile ride, we finally reach JAR-2 (Jakobshavn Ablation Region 2), where Dr. Koni Steffen of the University of Colorado at Boulder and NASAs Dr. Jay Zwally must conduct work on instruments that measure snowfall, wind speed, ice thickness and its movement toward the ocean.

Dr. Steffen warns us of dangerous crevices, then promptly steps in one, his left leg sinking up to the knee. I expected it to be there, based on that crack in the ice, he says with a grin. I just wanted to test my theory.

We move the snowmobiles away and vow not to approach the hole, while Dr. Zwally does the exact opposite. He methodically pokes at it with an aluminium pole, enlarging it. This is big enough that if you go down you may never come out, he says nonchalantly. It may be as big as the one that helicopter pilot fell in the other day. Then he ties himself to a snowmobile, leans over the crevice and starts videotaping it. Id say its at least 15 metres deep and wide enough for several of us to fit in it, he announces.

Most of the data from JAR-2 and other stations like it are beamed by satellite to the United States, but some must be downloaded locally. Dr. Steffens crew posts all of it on the Internet for anyone interested in climate change. Here are some of the facts their research here has helped determine:

• The winter temperature in Greenland has risen by some 5 degrees Celsius (9 Fahrenheit) over the last 15 years. Spring and fall temperatures have climbed by 3 degrees Celsius (5.4 Fahrenheit), while summer temperatures have remained constant.
• Over the last 30 years, the area of the ice cap that melts has grown by 30 percent. Every year, 100-150 cubic kilometers more ice melts than forms in Greenland.
• The ice cap is moving faster toward the coast. The glacier Swiss Camp rests on moves toward the coast at 14-15 kilometres (8.7-9.3 miles) a year, up from 6-7 kilometres (3.7-4.3 miles) a year in 1995.

For Dr. Steffen, todays job entails removing the solar-powered instruments from the pole theyre currently perched on and attaching them to a shorter base. Last years ice melt left the expensive equipment dangling 3 meters (9.8 feet) in the air, and with more melting expected this year, they will be vulnerable to the strong winds that sweep the ice cap.

Were already late, since Dr. Zwally had to turn his snowmobile around after 8 kilometres (5 miles) to look for his GPS unit. Thats a crucial piece of equipment on the ice cap, where every direction looks the same. If youre stranded and the wind blows away the snowmobile tracks, you have no chance of finding your way back to camp without a GPS unit.

By noon, the sun is warm enough to require 50 SPF sunscreen as Dr. Steffen uses a propane-powered steam drill to make a hole 7 meters (23 feet) in the ice for the new pole. The first three tries are unsuccessful, but the fourth is good. It can take as many as eight holes to get to the needed depth, so this is good news.

To lift the instruments off the old base, Dr. Steffen climbs a 3 metre (10 foot) crane precariously held upright by three people pulling on ropes while two others steady it from the bottom. As he sways back and forth, Dr. Steffen lifts the entire contraption onto the new pole, but another problem emerges: the two parts wont align closely enough for a bolt to fasten them together.

After several failed efforts to attach the instrument pole to its new base, someone calls for the ultimate solution: duct tape. They dont have any, because Dr. Steffen hates it, but they do have electrical tape. So they tape the two pieces together and drop them into the hole. Within hours, the water in the hole will freeze and anchor the new shorter set-up to the ice sheet, ensuring the steady flow of weather data will continue. Next year, Dr. Steffen will return here to check the instruments and will likely have to go through the whole exercise again.

Dr. Koni Steffen working on the Greenland ice cap. Photos by Bob Strong, Reuters.