During the last decade of rapid environmental change in the Arctic multiple studies have been conducted in the region of the Chukchi Sea and Bering Strait, which is the only Pacific-Arctic oceanic gateway. Current paper provides an overview of the research based on the recent in-situ hydrographic observations in the Chukchi Sea. We discuss the properties of the major water masses, their pathways on the shelf and at the shelfbreak, and changes in the circulation patterns. Anomalously strong northerly winds account for the transposition of the water masses in Bering Strait, as well as cause the Alaskan Coastal Current flow into the Herald Canyon. Previously unknown Chukchi Slope Current has been described emanating from the Barrow Canyon and flowing westwards over the upper continental slope. Mutliple studies discuss the variability of the Pacific Winter Water on the shelf and at the shelfbreak; the circulation of the Pacific Winter Water on the shelf has been revised. Atlantic Water has been observed far south on the Chukchi shelf associated with high polynya activity in the region.
Chukchi Sea, Chukchi Slope current, water masses, Bering Strait, Alaskan Coastal Current
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