The author(s) will give a talk

On the interannual variability of spring Bering Strait water temperatures

Lenetsky, Jed E 1 ; Serreze, Mark C 2

1 National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado – Boulder, Boulder, Colorado, USA
2 National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado – Boulder, Boulder, Colorado, USA

We find that June Bering Strait water temperatures, an important predictor of the timing of seasonal sea ice retreat in the economically important Chukchi Sea and surrounding region, are set upstream the preceding autumn and winter by ocean temperatures in the southwestern Bering Sea shelf. Positive ocean heat anomalies in autumn lead to delayed winter formation of sea ice in the western Bering sea and early ice retreat the following spring. These autumn heat anomalies exist from the surface to 65 meters depth and are preserved in the thermocline after winter freezing of surface waters. Heat anomalies move towards the Bering Strait via the Anadyr current and are magnified by shortwave radiation fluxes to the ocean surface in April and May. We show that the heat content of the Anadyr current, and not the atmospheric circulation, is the primary driver of Bering Strait water temperature variability. Water temperatures at depth in the Bering Sea Shelf are more closely linked to June Bering Strait water temperatures than are temperatures at the surface; December water temperature anomalies at 45 meters depth correlate with June Bering Strait water temperatures at r = 0.85. These findings highlight the importance of real time monitoring of temperatures at depth in the western Bering Sea for seasonal sea ice forecasting in the Chukchi Sea and surrounding areas and for understanding ice-associated ecological changes.

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