Impact of Convective Momentum Transport by Deep Convection on Simulation of Tropical Intraseasonal Oscillation  

作　　者：LING Jian LI Chongyin 

机构地区：[1]The State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics, Chinese Academy of sciences [2]Institute of Meteorology and Oceanography, PLA University of Science and Technology

出　　处：《Journal of Ocean University of China》2014年第5期717-727,共11页中国海洋大学学报（英文版）

基　　金：sponsored by the Joint Project of Natural Science Foundation of China and Yunnan Province (U0833602)

摘　　要：This paper focuses on the impacts of convective momentum transport(CMT) on simulations of the tropical intraseasonal oscillation(TIO) in SAMIL. Two sets of experiments are performed, which give different reality of the Madden-Julian Oscillation(MJO). The Tiedtke cumulus parameterization scheme is used for all experiments. It is found that simulations of the TIO can be influenced by CMT, and the impacts on the simulated TIO depend on the model capability in simulating the MJO. CMT tends to have large influences to the model that can simulate the eastward propagation of the MJO. CMT can further influence the long-term mean of zonal wind and its vertical shear. Zonal wind suffers from easterlies biases at low level and westerlies biases at upper level when CMT is introduced. Such easterlies biases at low level reduce the reality of the simulated tropical intraseasonal oscillation. When CMT is introduced in the model, MJO signals disappear but the model's mean state improves. Therefore, a more appropriate way is needed to introduce CMT to the model to balance the simulated mean state and TIO signals.This paper focuses on the impacts of convective momentum transport（CMT） on simulations of the tropical intraseasonal oscillation（TIO） in SAMIL. Two sets of experiments are performed, which give different reality of the Madden-Julian Oscillation（MJO）. The Tiedtke cumulus parameterization scheme is used for all experiments. It is found that simulations of the TIO can be influenced by CMT, and the impacts on the simulated TIO depend on the model capability in simulating the MJO. CMT tends to have large influences to the model that can simulate the eastward propagation of the MJO. CMT can further influence the long-term mean of zonal wind and its vertical shear. Zonal wind suffers from easterlies biases at low level and westerlies biases at upper level when CMT is introduced. Such easterlies biases at low level reduce the reality of the simulated tropical intraseasonal oscillation. When CMT is introduced in the model, MJO signals disappear but the model＇s mean state improves. Therefore, a more appropriate way is needed to introduce CMT to the model to balance the simulated mean state and TIO signals.

关 键 词：Madden-Julian Oscillation（MJO） convective momentum transport（CMT） SAMIL 

分 类 号：P433[天文地球—大气科学及气象学] P458.2