Observation of atmospheric methane in the Arctic Ocean up to 87° north

Although the Arctic methane reservoir is large, the emission of methane from the Arctic Ocean into the atmosphere remains poorly constrained. Continuous ship-borne measurements of atmospheric methane near the surface ocean were carried out during two cruises to investigate methane emission from the Arctic Ocean up to the latitude of 87°N. Three-day air mass back trajectories along the cruise tracks indicated that the surface Arctic Ocean could be a potentially important source of methane to the atmosphere. Rapid bursts in methane concentration occurred mainly along the ocean frontal area, suggesting that frontal upwelling in the upper layer of the Arctic Ocean might contribute to methane emissions into the atmosphere.