Variability and Predictability of the Bering Strait Ocean Heat Transport and Arctic Ocean Sea Ice Extent

Abstract

Background: This study examines the monthly, seasonal, and interannual variations in Pacific Ocean heat transport entering the Arctic Ocean through the Bering Strait, and its influence on sea ice extent in the Arctic Ocean. Methods: Monthly ocean heat transport is calculated using temperature and volumetric transport data from moorings deployed in the Bering Strait. Pearson correlations are calculated between the observed detrended monthly cumulative Bering Strait ocean heat transport and the detrended monthly sea ice extent time series from May through September. Results: An increase in the spring variability of the Bering Strait ocean heat transport is found since 2010, associated with both increased volume flux and water temperatures in May and June. A significant negative correlation between the Bering Strait ocean heat transport and Arctic sea ice extent in the Pacific sector is observed for May, June, and July, both within and outside the marginal ice zone, with a sharp decline in predictability for August and September. Conclusion: The Bering Strait ocean heat transport is a skillful predictor for early melt season sea ice extent in the Pacific sector but loses predictive skills later in the summer in August and September due to changes in ice dynamics, in accordance with the loss of predictive skill in Global Climate Models.