SWERUS-C3 scientists begin methane measurements in outer Laptev Sea

After nine days in transit, the Arctic expedition SWERUS-C3 has reached the first sampling station located in the Nansen Basin-Laptev Sea. The researchers focus on measuring methane emissions in the outer Laptev Sea. Areas where methane is “bubbling up” from the seabed will be studied in detail to understand how this system functions today.

Scientists took the first deep water and sediment samples at depths of over 3000 meters in the south-eastern Nansen Basin on 15 July. Sampling takes place above the continental slope to determine if warm water from the Atlantic that circulates at 200-500 m depth destabilizes frozen methane (stored as methane hydrates) along the East Siberian continental slope.

In previous expeditions to the East Siberian Arctic Ocean, SWERUS-C3 researchers discovered large amounts of old carbon and methane in this area, which is the world's biggest and perhaps most inaccessible of coastal seas. The methane measurements that are being carried out during SWERUS-C3 have two primary aims:

- Our new measurements will deepen our understanding of the findings from previous expeditions and will help pinpoint which part of the huge methane reservoirs in the seabed of the East Siberian Arctic Ocean this methane “bubbles up” from. This is necessary knowledge for predicting how methane emissions may develop in the future, says Örjan Gustafsson.

SWERUS-C3 will revisit a number of the methane “bubble-fields” to further study how these have changed over the past years. The expedition will also secure sediment cores that can shed light on how old carbon is released from thawing permafrost over time - from a thousand years down to a few years ago.