The international research expedition SWERUS-C3 with Swedish icebreaker Oden is on the homeward trajectory after nearly 100 days in the Arctic Ocean. Now, the “exciting process” of analysing samples and data collected during the trip awaits.

SWERUS-C3 is a two-leg Swedish-Russian-US cooperation that will investigate the linkages between climate, cryosphere and carbon. The expedition departed from Tromsø, Norway, on 5 July (leg1) and travelled along the Russian Arctic coast to reach Barrow, Alaska, where a change- over of research staff and crew took place on 20 August.  On 21 August SWERUS-C3 (leg 2) set off for its journey back to Tromsø, this time over the Lomonosov Ridge, an underwater mountain range.

“During the expedition's second leg we have studied the warm Atlantic water that flows into the Arctic Ocean and pockmarks at 900-meter depths as well as the enormous tracks on the ocean floor left by previous ice sheets found in the central Arctic Ocean,” says Martin Jakobsson, Professor at Stockholm University and chief scientist on leg 2. He continues: “The material will be able to provide new perspectives on Arctic sea ice development and history as well as stability of gas hydrates along the Arctic continental shelf.”

During the first leg, the researchers collected samples from the shallow outer part of the East Siberian Arctic Sea with the aim of understanding how thawing permafrost and gas hydrates could play a part in a carbon-climate feedback, enhancing the ongoing global warming process. “For the first time, elevated methane concentrations were detected in the seawater all the way up to the surface along the continental slope,” says Örjan Gustafsson, Professor at Stockholm University and chief scientist on leg 1.

About the icebreaker Oden
The icebreaker Oden is one of the world's foremost polar research vessels. SWERUS-C3 is Oden’s twentieth polar research expedition. Besides being an excellent icebreaker, Oden carries advanced research equipment such as a multi-beam sonar, winches for sampling, sea water intake for continuous sampling, permanent laboratories and communications systems, as well as extensive knowledge and expertise among its crew and support staff at the Swedish Polar Research Secretariat. “After several years of planning work by the researchers and the Swedish Polar Research Secretariat, it is very gratifying to see how well the expedition was carried out,” says Björn Dahlbäck, director of the Swedish Polar Research Secretariat.

The research work on SWERUS-C3 was made possible thanks to the Knut and Alice Wallenberg Foundation.