Nonlinear transport across the Bering Strait with sill depth shoaling

At ~50m deep, the Bering Strait is the only direct connection between the Pacific and Arctic Oceans and allows for significant transport of fresh water and heat to the Arctic. Though it is expected that times of lower sea level in Earth’s history would have modified flow through the Bering Strait, the sensitivity of Bering Strait transport to sea level has not been quantitatively described. Here we use a high resolution regional Arctic configuration of MITgcm to assess seasonal and annual transport under varying sill depths. Simulations demonstrate that the yearly average volume transport through the Strait remains ~1 Sv at depths of 50 to 30m, and decreases only to 0.85 Sv at 20m. Each shallower simulation has a reduced seasonality of flow. These results have implications for heat transport to the Arctic when the Bering Strait was shallower than today, including during the early Holocene.