Purpose. The aim of the study is to specify the quantitative characteristics of water exchange through the Near Strait (Aleutian Islands) using the modern oceanographic reanalysis data, to assess the seasonal and interannual variability of water volume transfer, and to identify the key factors affecting water dynamics in the strait.
Methods and Results. The following methods were applied to quantify water exchange through the Near Strait: 1) analysis of the CMEMS data (1993–2021) for determining daily average water volume transfer and its seasonal variability; 2) comparison of the data of two CMEMS products for the study region: GLORYS12V1 (DT) ocean reanalysis and GLOBAL_ANALYSISFORECAST (NRT) operational forecast; 3) comparison of the CMEMS-based estimates with those from the Japanese JCOPE2M and American
GOFS 3.1 reanalyses for the above-mentioned area. The performed investigation made it possible to establish that during some years, the average daily water volume transfer from the Pacific Ocean into the Bering Sea exceeded 15 Sv (1 Sv = 106 m3
/s), whereas in other periods, the reverse water flow reaching up to 5 Sv was observed. A pronounced seasonal variability in the daily water transfer, namely its maximum values in winter and minimum ones in summer, was revealed. Significant discrepancies between the data derived from different reanalysis products (CMEMS, JCOPE2M, and GOFS 3.1) were identified.
Conclusions. The estimates of water volume transfer and exchange through the Near Strait derived from four different datasets show substantial variations indicating a complex nature of local circulation. Therefore different reanalyses reproduce its features in different ways. The obtained results point out
the need for further research using field observations.