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The animation below shows evolution of the potential temperature on the surface of constant potential density (or "isopycnal" surface, sigma = 26.4 kg/m3) in the southeastern part of the Bering Sea deep basin. This is based on the realistic 2-km resolution model simulation for July-August 2009 (Durski et al., 2015). This surface is found at the depths of 200-300 m below the sea level. Away from the Aleutian Island slopes in the south and shelf slope in the northeast, temperature on this surface can be considered as a passive tracer. Along the Aleutian Islands warmer temperature is a result of intensive vertical mixing by tides (primarily diurnal). This warmer temperature is advected along the Aleutian North Slope to the east by the Aleutian Island North Slope Current (ANSC). This current reaches the Bering Canyon, where it turns to northwest and continues as the Bering Slope Current (BSC). The warmer water is entrained into interior ocean by the eddies developed on spatial scales of 20-100 km, originated in the ANSC and BSC. Amchitka Pass is recognized as the largest producer of the warmer water that will be advected into the basin on this isopycnal surface. Note that at this subsurface level the ANSC water temperature is warmer than the Pacific water. The model is developed by Scott Durski. The animation and analysis is by Matthew Mauch, our MSc student.