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Abstract We investigate the role of ocean heat transport (OHT) in driving the decadal variability of the Arctic climate by analyzing the pre‐industrial control simulation of a high‐resolution climate model. While the OHT variability at 65°N is greater in the Atlantic, we find that the decadal variability of Arctic‐wide surface temperature and sea ice area is much better correlated with Bering Strait OHT than Atlantic OHT. In particular, decadal Bering Strait OHT variability causes significant changes in local sea ice cover and air‐sea heat fluxes, which are amplified by shortwave feedbacks. These heat flux anomalies are regionally balanced by longwave radiation at the top of the atmosphere, without compensation by atmospheric heat transport (Bjerknes compensation). 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 coarse‐resolution ocean models.
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Influence of Anomalous Ocean Heat Transport on the Extratropical Atmospheric Circulation in a High‐Resolution Slab‐Ocean Coupled Model
Abstract Key questions remain about the atmospheric response to variability in the oceanic western boundary currents (WBCs). Here we exploit a unique high‐resolution slab‐ocean coupled climate model to investigate how ocean heat transport (OHT) anomalies in the major WBCs of both hemispheres affect the atmospheric circulation. Prescribed OHT anomalies lead to robust changes in convective precipitation anomalies equatorward of the maximum surface warming. The response is deepest and most pronounced over the Northern Hemisphere (NH) WBCs, where it is associated with significant changes in upper tropospheric vertical motion, condensational heating and geopotential heights. The response is relatively shallow over the Southern Hemisphere (SH) WBCs. The findings reveal the robustness of the atmospheric response to OHT anomalies and highlight key hemispheric differences: in the NH, OHT anomalies are balanced by deep atmospheric vertical motion; in the SH, they are balanced primarily by shallow horizontal temperature advection.
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- Award ID(s):
- 2055121
- PAR ID:
- 10575268
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 52
- Issue:
- 4
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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