Air composition over the Russian sector of the Arctic in September 2020. 1. Methane
O.Yu. Antokhina1, P.N. Antokhin1, V.G. Arshinova1, M.Yu. Arshinov1, B.D. Belan1, S.B. Belan1, E.V. Guruleva1, D.K. Davydov1, G.A. Ivlev1, A.V. Kozlov1, K. Law2, T.M. Rasskazchikova1, J.-D. Paris3, D.E. Savkin1, D.V. Simonenkov1, T.K. Sklyadneva1, G.N. Tolmachev1, A.V. Fofonov1
1V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
2Laboratoire AtmosphГЁres, Milieux, Observations Spatiales, Paris, France
3Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, CNRS-CEA-UVSQ, Gif-sur-Yvette, France
Keywords: Arctic, atmosphere, air, vertical distribution, methane, greenhouse gases, transport, impurities, composition
Abstract
In the Arctic, global warming is 2-3 times faster than over other regions of the globe. As a result, noticeable changes are already being recorded in all areas of the environment. However, there is very little data on such changes in the Russian Arctic. Therefore, to fill the gap in the data on the vertical distribution of the gas and aerosol composition of air in this region, an experiment was carried out on the Tu-134 Optical laboratory aircraft in September 2020 to sound the atmosphere and water surface over the water areas of all seas in the Russian Arctic. This paper analyzes the spatial distribution of methane. It is shown that during the experiment its concentration was the highest over the Kara Sea (2090 ppb), the lowest over the Chukchi Sea (2005 ppb). The East Siberian and Bering seas were slightly different from the Chukchi Sea in its content. Average values of CH4 are characteristic of the Barents (2030 ppb) and the Laptev Seas (2040 ppb). The difference in the concentrations between the level of 200 meters and the free troposphere reached 150 ppb over the Kara Sea, decreased to 91 and 94 ppb over the Barents and Laptev Seas, and further decreased over the East Siberian, Chukchi and Bering Seas to 66, 63 and 74 ppb, respectively. Horizontal heterogeneity in the distribution of methane over the Arctic seas is the greatest over the Laptev Sea, where it reaches 73 ppb. It is 2 times higher than over the Barents and Kara Seas, and 5-7 times higher than over the East Siberian and Bering Seas.
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