Numerical Study of Interactions Between Mesoscale Convective Systems and Ocean Mixed-Layer in the Western Pacific Warm Pool Using a Nested-Grid Coupled Ocean-Atmopshere Mesoscale

拉曼：西太平洋的气象并不为人所知，但对全球气候有很大的影响。一个名为热带海洋全球大气耦合海洋-大气响应实验（TOGA COARE）的野外项目，其目标之一是增加对西太平洋中尺度对流系统（MCS）特征的了解。特别令人感兴趣的是，相对于单个积雨云，MCSs有可能显著改变大面积内的海气动量、热量和水分通量。首席研究员将使用嵌套网格、海洋-大气耦合中尺度模式，调查并定量描述西太平洋暖池（WPWP）中MCSs与海洋混合层之间的相互作用。具体目标包括：(i)提高对WPWP对海洋大气边界层平衡和瞬态结构影响的认识；确定并量化与暖池上方MCSs相关的风、气温和降水对海洋混合层水平和垂直密度分布以及对海气热通量和水汽通量的反馈效应；确定和量化对流和中尺度过程引起的海热和水汽通量、海表温度和海表温度梯度变化对对流和中尺度事件后续发展的反馈效应；（iv）利用耦合的中尺度模式同化大气和海洋边界层的重要参数。这项研究的成功完成将有助于提高对MCS对厄尔尼诺等行星尺度事件影响的认识。＊＊＊

9632390 Raman The meteorology over the Western Pacific Ocean is not well-known, but has a great influence on the global climate. A field program named the Tropical Ocean Global Atmosphere, Coupled Ocean-Atmosphere Response Experiment (TOGA COARE) had as one of its objectives to increase understanding of the characteristics of mesoscale convective systems (MCS) over the Western Pacific. Of special interest is the potential for MCSs to significantly modify air-sea momentum, heat and moisture fluxes over a large area relative to that of an individual cumulonimbus cloud. The Principal Investigator will investigate and quantitatively describe the interactions between MCSs and the ocean mixed layer in the Western Pacific warm pool (WPWP) using a nested-grid, coupled ocean-atmosphere mesoscale model. Specific objectives include: (i) improve understanding of the effect of the WPWP on the equilibrium and transient structures of the marine atmospheric boundary layer; (ii) identify and quantify the feedback effect of wind, air temperature and precipitation associated with MCSs over the warm pool on the horizontal and vertical density distributions of the ocean mixed-layer, and on the air-sea heat and moisture fluxes; (iii) identify and quantify the feedback effect of changes in air-sea heat and moisture fluxes, sea surface temperature and sea surface temperature gradients due to convective and mesoscale processes on subsequent development of convective and mesoscale events; (iv) assimilate important parameters in the atmospheric and oceanic boundary-layers using a coupled mesoscale model. Successful completion of this research will assist in improving knowledge of the impact of MCS on planetary scale events such as El Nino. ***