热带太平洋对风应力拖曳系数响应的敏感性试验  

Sensitivity experiments of the response of tropical Pacific to the wind stress in an Oceanic General Circulation Model

作　　者：吴海燕 张铭[2] 李崇银[2,3] 

机构地区：[1]解放军94855部队 [2]解放军理工大学气象学院 [3]中国科学院大气物理研究所LASG实验室

出　　处：《海洋预报》2009年第2期34-43,共10页Marine Forecasts

基　　金：国家"973"项目(2007CB411805)

摘　　要：为了检验一个准全球的海洋环流模式中热带太平洋对风应力变化的响应,使用NCEP月平均再分析资料计算的强迫场强迫该模式进行控制试验,在(10.5°S～9.5°N,159.75°E～110.25°W)的区域增大或减小风应力拖曳系数进行敏感性试验,并把试验结果与同时段的SODA资料进行分析比较。该模式基本能模拟出海洋环流的基本气候态,但是对一些细节描述还不够准确。试验结果表明,风应力减小时可以改善模式对热带东太平洋冷舌的模拟,而对次表层温度和流场的刻画能力较弱。增大风应力则对次表层温度和流场的模拟有所改善。通过对模式中热量收支的分析可知,平流过程、扩散过程对热带太平洋海表温度的变化起到了重要的作用;海表面热交换可以促使海温距平向相反的方向发展。垂直输送对赤道中东太平洋表层的降温起重要作用,抑制了次表层的增暖,水平平流过程则促进了赤道太平洋次表层的增暖。Sensitivity experiments are done to evaluate the response of tropical Pacific to the wind stress in an Oceanic General Circulation Model. Three different wind stress deriving from NCEP monthly mean reanalysis data are used to force the model, which are original computed stress data（called control experiment） and increasing or decreasing drag coefficient in the area （ 10.5°S - 9.5 °N, 159.75 °E - 110.25°W） （called sensitivity experiments ） ,and then compare the results with the contemporaneous SODA reanalysis data. The results show that reducing the wind stress can improve the ability to simulate sea surface temperature （SST）, but weaken the ability to simulate the temperature and flow in subsurface, while the case is different when increasing the wind stress. Advection and diffusion terms are important to the SST change, while surface heat flux makes SST changing to the inverse direction. Vertical transportation plays important role in SST cooling in equatorial central and east pacific, and restrains temperature warming in subsurface. Horizontal advection promotes temperature wanning in subsurface. Although this model can simulate the basic climatic form, many schemes, such as improving resolution, adjudting wind stress, changing mix schemes, should be altered to improve the simulation ability.

关 键 词：海洋环流模式 风应力 拖曳系数 敏感性试验 

分 类 号：P731[天文地球—海洋科学]