Hydrological Structure and Water Dynamics in the Powell Basin in January–February 2022

Abstract

In January–February 2022, a CTD/LADCP section across the Powell Basin in the Weddell Sea with hydrochemical observations was carried out in the Antarctic expedition of the R/V “Akademik Mstislav Keldysh”. Transect was located from the Antarctic Peninsula to the South Orkney Islands; thus, it crossed the Weddell Gyre in its northwestern part. As a result, we collected new data about hydrological structure and water dynamics in this area. In this study, we present new results on the data analysis related to the structure of the Weddell Gyre, Antarctic Bottom Water formation, as well as variability of hydrophysical and hydrochemical characteristics of waters in the Powell Basin. Only two of the three currents, Antarctic Coastal Current and Antarctic Slope Front, were identified in the structure of the Weddell Gyre. Velocities of these currents were about 10–15 cm/s. The structure of waters was typical for the Weddell Sea, but a change in the temperature maximum was recorded in the layer of Warm Deep Water.