Spring Cold Bias of SST and Minimal Wind Mixing in the Equatorial Pacific Cold Tongue  

作　　者：LIN Peng-Fei LIU Hai-Long LI Chao ZHANG Xue-Hong 

机构地区：[1]State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of AtmosphericPhysics, Chinese Academy of Sciences, Beijing 100029, China

出　　处：《Atmospheric and Oceanic Science Letters》2010年第6期342-346,共5页大气和海洋科学快报（英文版）

基　　金：supported by the National Basic Research Program of China (Grant Nos. 2010CB950502, 2010CB951904,and 2010AA012303);LASG Free Exploration Fund;the National Natural Science Foundation of China (Grant Nos. 40906012 and 40775054)

摘　　要：The authors investigate the relationship between bias in simulated sea surface temperature （SST） in the equatorial eastern Pacific cold tongue during the boreal spring as simulated by an oceanic general circulation model （OGCM） and minimal wind mixing （MWM） at the surface. The cold bias of simulated SST is the greatest during the boreal spring, at approximately 3℃. A sensi- tivity experiment reducing MWM by one order of magnitude greatly alleviates cold biases, especially in March-April. The decrease in bias is primarily due to weakened vertical mixing, which preserves heat in the uppermost layer and results in warmer simulated SST. The reduction in vertical mixing also leads to a weak westward current in the upper layer, which further contributes to SST warming. These findings imply that there are large uncertainties about simple model parameters such as MWM at the oceanic surface.The authors investigate the relationship between bias in simulated sea surface temperature(SST)in the equatorial eastern Pacific cold tongue during the boreal spring as simulated by an oceanic general circulation model(OGCM)and minimal wind mixing(MWM)at the surface.The cold bias of simulated SST is the greatest during the boreal spring,at approximately 3°C.A sensitivity experiment reducing MWM by one order of magni-tude greatly alleviates cold biases,especially in March-April.The decrease in bias is primarily due to weakened vertical mixing,which preserves heat in the uppermost layer and results in warmer simulated SST.The reduction in vertical mixing also leads to a weak westward current in the upper layer,which further contributes to SST warming.These findings imply that there are large uncertainties about simple model parameters such as MWM at the oceanic surface.

关 键 词：cold biases the equatorial Pacific cold tongue the minimal wind mixing 

分 类 号：P731.11[天文地球—海洋科学] X16[环境科学与工程—环境科学]