Between May 2001 and September 2003, a series of moorings were deployed in four of the Aleutian Passes – Tanaga Pass (12 months of data), Akutan Pass and Seguam Pass (18 months), and Amukta Pass (36 months). Instruments on each mooring measured temperature, salinity and current velocity. Tidal currents dominated the flow in each pass, including a strong fortnightly component in the three deeper passes (Tanaga, Seguam, and Amukta). Net transport in each of the passes was northward, varying from 0.1 × 106 m3 s−1 in Akutan Pass and 0.4 × 106 m3 s−1 in Seguam to >4.0 × 106 m3 s−1 in Amukta Pass. The transport in Amukta Pass, calculated from current meters, was approximately five times as large as previously estimated from hydrographic surveys. At monthly and longer periods, the variability in transport in Amukta Pass was related to the position and strength of the Alaskan Stream southeast of the pass. Vertical mixing was examined in Akutan and Seguam Passes. Strong tidal currents mix the water column top‐to‐bottom over the shallow sills in the passes, a depth of 80 m in Akutan and 140 m in Seguam Pass, providing a critical source of nutrients to the Bering Sea ecosystem.

a b s t r a c tMore than 20 years of data from moorings, satellite-tracked drifters and hydrographic surveys are integrated to provide a comprehensive view of currents and transport on the eastern Bering Sea shelf. The major sources of water onto the eastern Bering Sea shelf are North Pacific water flowing through Unimak Pass and Bering Slope water flowing onto the shelf usually via the canyons that intersect the shelf break. Absolute geostrophic transport through Unimak Pass varies from an average of 0.25 Â 10 6 m 3 s À 1 (Sv) in the warm months to 0.43 Sv in the cold months. Flow along the 50-m isobath is weak, with a transport of o0.1 Sv (calculated from current meters) in summer and fall. The transport along the 100-m isobath measured at two locations is more than twice that along 50-m isobaths; in the summer at the Pribilof Islands it was 0.2 Sv and during spring and summer at 60°N the northward geostrophic transport (referenced to the bottom) was 0.31 Sv. Northward transport along the 100-m and 50-m isobaths accounts for approximately half of the transport through Bering Strait. A typical transit time from Unimak Pass to Bering Strait is 413 months and from Amukta Pass to Bering Strait via the Bering Slope Current is 48 months. Consequently, the source of most of the heat transported into the Arctic through Bering Strait is a result of air-sea interactions local to the northern Bering Sea. Analysis of the currents and water properties on the southern shelf indicates that $ 50% of the shelf water is exchanged with slope water during October-January each year. This exchange elevates the October midshelf average nitrate level from 6 μM to 14-16 μM by the end of January.

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