Home from the North Pole

Cruise track of the USCG Icebreaker Healy during the 2005 trans Artic expedition

6 Jan 06 -- Hanover, N.H. -- Recently, scientists at the U.S. Army Engineer Research and Development Center's (ERDC) Cold Regions Research and Engineering Laboratory (CRREL) returned from a two-month expedition across the Arctic Ocean aboard the U.S. Coast Guard (USCG) Icebreaker Healy. This 4,500-mile voyage of scientific discovery started in Dutch Harbor, Alaska, Aug. 5. The Healy traveled northward across the Bering Sea, Chukchi Sea, and the Arctic Ocean, rendezvousing with the Swedish Icebreaker Oden, Sept. 1. The ships continued northward together, reaching the North Pole, Sept. 12. The transect of the Arctic Ocean was completed by sailing south through the Arctic Ocean and Greenland Sea, ending in Tromso, Norway, Sept. 30.

CRREL researchers Dr. Donald Perovich and Bruce Elder were aboard the Healy, leading studies of the morphological and optical properties of the Arctic sea ice cover. Arctic temperatures are so cold the ocean surface freezes. Sea ice covers an area comparable to the size of the United States, but is only a veneer several feet thick floating on the ocean. Scientists believe this sea ice cover is a key indicator and potential amplifier of global climate change. Perovich, a senior research geophysicist, and Elder, a physical scientist are veterans of dozens of polar field campaigns, but this was their first trip to the pole. Their goal was to determine the state of the sea ice cover, how much of the ocean was ice-covered, how thick the ice was, and what the ice surface conditions were. 

Arriving at the North Pole from left to right: Bruce Elder, CRREL, Tom Grenfell, University of Washington, Jeremy Harbeck, University of Washington and University of Alaska, Fairbanks, and Dr. Donald Perovick, CRREL.

"This cruise is a tremendous opportunity to take the pulse of the Arctic sea ice cover," Perovich said. "We will compare our observations to satellite results and previous field experiments to investigate the changes occurring in the ice cover."  

The Arctic sea ice cover may amplify climate change through positive feedbacks such as the ice-albedo feedback. The albedo is simply the fraction of sunlight reflected by the surface. The snow-covered sea ice reflects most (more than 80 percent) of the incident sunlight, but some is absorbed. This absorbed sunlight leads to melting, which in turn lowers the albedo, resulting in more absorbed sunlight, increasing melting, and lowering the albedo even more. Perovich and Elder made extensive measurements of the albedo examining variations both in space and time. 

Even though the experiment has ended, the measurements will continue. The team left four autonomous buoys to measure air temperature, ice drift, and ice growth and melting for the next three years. 

"The buoys can last three years, sending us data by satellite every day. It's the next best thing to being there," Elder, the builder of the buoys, said. 

To learn more about and view the images of this National Science Foundation-funded project, visit the Ice Team's Trans-Arctic Expedition webpage at http://psc.apl.washington.edu/arctic_basin/. 

CRREL is one of seven laboratories that make up the ERDC. The ERDC is the premier research and development facility for the U.S. Army Corps of Engineers with more than 2,000 employees, $1.2 billion in facilities, and an annual research program approaching $700 million. It conducts research in both military and civil works mission areas for the Department of Defense and the nation. CRREL is the only Department of Defense Laboratory addressing problems and opportunities unique to the world's cold regions. Located in Hanover, N.H., CRREL also has field offices in Fairbanks and Anchorage, Alaska.