Bering Strait Ocean Heat Transport Drives Decadal Arctic Variability in a High-Resolution Climate Model

We investigate the role of ocean heat transport (OHT) in driving the decadal variability of the Arctic climate by analyzing the pre-industrial control integration of a high-resolution climate model. In particular, we explore the responses of the Arctic to OHT variability in the Atlantic and through the Bering Strait in the Pacific. While the OHT variability at 65N is much stronger in magnitude in the Atlantic, we find that the decadal variability of Arctic-wide surface temperature and sea ice cover is much better correlated with Pacific OHT than Atlantic OHT, suggesting an outsized role of OHT through Bering Strait in modulating Arctic climate. OHT anomalies from the Pacific cause significant changes in atmospheric heat content in the Pacific sector of the Arctic, amplified by a strong ice albedo feedback. In contrast to the Atlantic, this heat anomaly is not removed by lateral transport, but instead regionally balanced by longwave radiation at the top of the atmosphere. The sensitivity of the Arctic to changes in OHT may thus rely on an accurate representation of the heat transport through the Bering Strait, which is difficult to resolve in low-resolution ocean models.