Study of State and Variability of the Japan and Okhotsk Seas in the 77th Cruise of the R/V <i>Professor Gagarinskiy</i> and 97th Cruise of the R/V <i>Akademik M.A. Lavrentyev</i>

Investigation of interannual and short-term variability of the water parameters in the Japan and Okhotsk seas and their ecological state were continued in the cruises No. 77 of the R/V Professor Gagarinskiy and No. 97 of the R/V Akademik M.A. Lavrentyev in fall-winter season of 2021. CTD profiling and water sampling for chemical analyses including methane and radioisotopes were implemented. A mooring of bottom autonomous station was deployed for 2.5 month. The long-term trend of the bottom water warming, eutrophication and acidification of the Japan Sea have been confirmed. The features of the fall-winter restructuring of the field of currents of the northern part of the Sea of Japan, the multifrontality of the Sakhalin upwelling structure, and the bimodality of the Primorye Current are shown.