Areas of the water column where bubbles continuously rise from bottom sediments, detected in all of the world's oceans, are called seeps. Direct measurements of the gas mixture composition carried by the bubbles have shown that it is dominated by one of the main greenhouse gases – methane [1, 2]. Shallow-water seeps discovered in the East Siberian Arctic Shelf area in the Laptev Sea are of significant interest. It has been established that these seeps are confined to areas of the seabed where subsea permafrost has lost its integrity [3, 4].

Continuous measurements of atmospheric methane concentration, conducted since 1983, illustrate the presence of a planetary maximum in the Northern Hemisphere of the Earth. Moreover, this value increases annually, which may imply regional sources, one of which is shallow-water seeps. A forecast of the dynamics of the changes in atmospheric methane concentration for the Northern Hemisphere predicts a continuous annual increase in its maximum value, with the possibility of large-scale single releases. However, due to the poor study of the region, these events will not be able to be registered until at least 10 years from now, and the resulting effect will lead to irreversible environmental, natural, technological, and social disasters [5, 6].

In 2018, during a comprehensive oceanographic expedition of the R/V Akademik Mstislav Keldysh, in the shallow part of the Laptev Sea, in Buor-Khaya Bay at depths from 20 to 25 meters, the team of authors registered over 100 previously unknown seeps. These areas were confirmed twice, in 2019 and 2020. This paper presents the first results of hydroacoustic studies of these shallow-water seeps. Their spatial variability was determined, and an estimate was obtained for the amount of methane transported by these areas from bottom sediments into the water and into the surface layer of the atmosphere.

The work was carried out within the framework of the projects: №FEFF-2024-0004, Priority 2030 TSU, №124022100074-9 и №124022100083-1.

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