Propagation of Intermediate Waters in the North Atlantic

Based on the latest data on temperature, salinity, and current velocities obtained during the 64th cruise of R/V Akademik Ioffe in November 2023, hydrological sections from the WODB23 database, and the GLORYS12v1 reanalysis, circulation patterns of Antarctic Intermediate Water (AAIW) and Mediterranean Sea Water (MSW) in the subtropical part of the North Atlantic were constructed. It has been shown that MSW in the studied area spreads in a system of several large gyres, while the AAIW movement occurs mainly along the coasts of Africa and America with the quasi-latitudinal transport between these branches in the tropical part of the Atlantic. The distribution limits of Antarctic Intermediate Water can vary from 20° to 45° N. The southern boundary of the Mediterranean Sea Water distribution is not the 35 PSU isohaline, but the area of its transition into the deep layer. The AAIW and MSW boundaries is a zone between 20° and 45° N where both water masses are present. The obtained limits of distribution of intermediate waters differ from the classical boundaries and complement the ideas about the structure and circulation of waters in the intermediate layer.