Interannual biases induced by freshwater flux and coupled feedback in the tropical Pacific

IOCAS-IR > 海洋环流与波动重点实验室

	Interannual biases induced by freshwater flux and coupled feedback in the tropical Pacific
	Zhang Ronghua; Wang Guihua; Chen Dake; Busalacchi, A. J.; Hackert, E. C.
	2010-05
发表期刊	MONTHLY WEATHER REVIEW
卷号	138 期号:5 页码:1715-1737
摘要	Freshwater flux (FWF) forcing induced feedback has not been represented adequately in many coupled ocean-atmosphere models of the tropical Pacific. Previously, various approximations have been made in representing the FWF forcing in climate modeling. In this article, using a hybrid coupled model (HCM), sensitivity experiments are performed to examine the extent to which this forcing and related feedback effects can contribute to tropical biases in interannual simulations of the tropical Pacific. The total FWF into the ocean, represented by precipitation (P) minus evaporation (E), (P - E), is separated into its climatological part and interannual anomaly part: FWF(Total) = (P - E)(clim) + FWF(inter). The former can be prescribed (seasonally varying); the latter can be captured using an empirical model linking with large-scale sea surface temperature (SST) variability. Four cases are considered with different FWF(inter) specifications: interannual (P - E) forcing [FWF(inter) = (P - E)(inter)], interannual P forcing (FWF(inter) = P(inter)), interannual E forcing (FWF(inter) = -E(inter)), and climatological (P - E) forcing (FWF(inter) = 0.0), respectively. The HCM-based experiments indicate that different FWF(inter) approximations can modulate interannual variability in a substantial way. The HCM with the interannual (P - E) forcing, in which a positive SST - (P - E)(inter) feedback is included explicitly, has a reasonably realistic simulation of interannual variability. When FWF(inter) is approximated approximated in some ways, the simulated interannual variability can be modulated significantly: it is weakened with the climatological (P - E) forcing and is even more damped with the interannual E forcing but is exaggerated with the interannual P forcing. Quantitatively, taking the interannual (P - E) forcing run as a reference, the Nino-3 SST variance can be reduced by about 12% and 26% in the climatological (P - E) forcing run and interannual E forcing run, respectively, but overestimated by 11% in the P(inter) forcing run. It is demonstrated that FWF can be a clear bias source for coupled model simulations in the tropical Pacific.
关键词	Sea-surface Temperature General-circulation Model Nino-southern Oscillation Layer Ocean Model El-nino Equatorial Pacific Mixed-layer Climate Models Heat Fluxes Salinity
收录类别	SCI
语种	英语
文献类型	期刊论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/18183
专题	海洋环流与波动重点实验室
推荐引用方式 GB/T 7714	Zhang Ronghua,Wang Guihua,Chen Dake,et al. Interannual biases induced by freshwater flux and coupled feedback in the tropical Pacific[J]. MONTHLY WEATHER REVIEW,2010,138(5):1715-1737.
APA	Zhang Ronghua,Wang Guihua,Chen Dake,Busalacchi, A. J.,&Hackert, E. C..(2010).Interannual biases induced by freshwater flux and coupled feedback in the tropical Pacific.MONTHLY WEATHER REVIEW,138(5),1715-1737.
MLA	Zhang Ronghua,et al."Interannual biases induced by freshwater flux and coupled feedback in the tropical Pacific".MONTHLY WEATHER REVIEW 138.5(2010):1715-1737.

条目包含的文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
Interannual Biases I（4689KB）			限制开放	CC BY-NC-SA	浏览