DOI: 10.1007/s00382-017-3896-2
Scopus记录号: 2-s2.0-85029540713
论文题名: Causes of the large warm bias in the Angola–Benguela Frontal Zone in the Norwegian Earth System Model
作者: Koseki S. ; Keenlyside N. ; Demissie T. ; Toniazzo T. ; Counillon F. ; Bethke I. ; Ilicak M. ; Shen M.-L.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2018
卷: 50, 期: 2018-11-12 起始页码: 4651
结束页码: 4670
语种: 英语
英文摘要: We have investigated the causes of the sea surface temperature (SST) bias in the Angola–Benguela Frontal Zone (ABFZ) of the southeastern Atlantic Ocean simulated by the Norwegian Earth System Model (NorESM). Similar to other coupled-models, NorESM has a warm SST bias in the ABFZ of up to 8 °C in the annual mean. Our analysis of NorESM reveals that a cyclonic surface wind bias over the ABFZ drives a locally excessively strong southward (0.05 m/s (relative to observation)) Angola Current displacing the ABFZ southward. A series of uncoupled stand-alone atmosphere and ocean model simulations are performed to investigate the cause of the coupled model bias. The stand-alone atmosphere model driven with observed SST exhibits a similar cyclonic surface circulation bias; while the stand-alone ocean model forced with the reanalysis data produces a warm SST in the ABFZ with a magnitude approximately half of that in the coupled NorESM simulation. An additional uncoupled sensitivity experiment shows that the atmospheric model’s local negative surface wind curl generates anomalously strong Angola Current at the ocean surface. Consequently, this contributes to the warm SST bias in the ABFZ by 2 °C (compared to the reanalysis forced simulation). There is no evidence that local air-sea feedbacks among wind stress curl, SST, and sea level pressure (SLP) affect the ABFZ SST bias. Turbulent surface heat flux differences between coupled and uncoupled experiments explain the remaining 2 °C warm SST bias in NorESM. Ocean circulation, upwelling and turbulent heat flux errors all modulate the intensity and the seasonality of the ABFZ errors. © 2017, The Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109274
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Geophysical Institute, University of Bergen, Bjerknes Centre for Climate Research, Bergen, Norway; Uni Research Climate, Bjerknes Centre for Climate Research, Bergen, Norway; Nansen Environmental and Remote Sensing Centre, Bjerknes Centre for Climate Research, Bergen, Norway
Recommended Citation:
Koseki S.,Keenlyside N.,Demissie T.,et al. Causes of the large warm bias in the Angola–Benguela Frontal Zone in the Norwegian Earth System Model[J]. Climate Dynamics,2018-01-01,50(2018-11-12)