GAMIL1.0大气模式模拟的西北太平洋夏季风:阵风参数化方案的影响  

The Western North Pacific Summer Monsoon Simulated by GAMIL 1.0:Influences of the Parameterization of Wind Gustiness

作　　者：刘晓娟[1,2] 周天军[1] 张丽霞[1,2] 邹立维[1,2] 吴波[1] 李忠贤[3] 

机构地区：[1]中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室,北京100029 [2]中国科学院研究生院,北京100049 [3]南京信息工程大学气象灾害省部共建教育部重点实验室,南京210044

出　　处：《大气科学》2011年第5期871-884,共14页Chinese Journal of Atmospheric Sciences

基　　金：国家自然科学基金资助项目40890054;40821092;国家科技支撑计划2007BAC29B03

摘　　要：本文分析了中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室(LASG/IAP)发展的大气环流格点模式(GAMIL1.0)对1980~1999年西北太平洋夏季风的模拟,讨论了阵风参数化方案对模拟效果的影响。结果表明:GAMIL1.0能合理再现西北太平洋夏季风气候态和年际变率的主要特征,不足之处在于其模拟的平均态及年际变率的强度都较之观测偏弱。引入阵风参数化方案后,模拟得到明显改进:区域平均的气候态降水由5.71 mm/d增加到8.35 mm/d,与观测值9.11 mm/d更为接近;模拟的季风指数与观测的相关系数由0.66上升到0.82;年际变率的振幅也显著增强,与观测更一致;模拟的"季风—ENSO"关系与观测几乎完全一致。对潜热通量、加热率和辐散环流的分析表明:降水平均态的改进来自阵风方案带来的潜热通量增加,年际变率模拟的改进与平均态的改进有关。引入阵风方案后,暖池地区的表面风速增加、潜热通量增强、降水增加,平均态更接近观测;合理的平均态降水使得模式对El Ni^no型海温异常的响应更为合理。这在加热场、对流层上层的异常辐合中心上都有清楚体现。The performance of GAMIL 1.0,a grid atmospheric model developed by the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,in simulating the western North Pacific summer monsoon is investigated.Influence on the simulation exerted by the inclusion of wind gustiness parameterization is discussed.Results show that major features of both the mean state and interannual variability of WNPSM are reasonably reproduced in the original version,but the strength is underestimated.After the inclusion of wind gustiness parameterization,improvements are obvious and mainly displayed as follows： the regional mean precipitation increases from 5.71 mm/d to 8.35 mm/d,which is more close to the observation;the correlation coefficient between the simulated and observed monsoon indices increases from 0.66 to 0.82;the amplitude of interannual variability becomes larger;more important,the simulated ＂ENSO-monsoon＂ relationship is almost the same as the observation.Analyses on the latent heat flux,heating rate,and divergent circulation indicate that the improvement in the mean state should be attributed to the enhancement of surface latent heating over the western North Pacific region.The improvement of interannual variability is related to the better mean state.The inclusion of wind gustiness parameterization leads to stronger surface wind speed,which enhances the surface latent heating.Then the mean precipitation is increased,indicating that the climate mean precipitation is improved.Following the improvement of climatological mean precipitation,the model＇s response to El Nin^o-type SST forcing is significantly improved,which is evident for both the heating field and corresponding upper-tropospheric convergence center in the western North Pacific.

关 键 词：西北太平洋夏季风 年际变率 阵风参数化方案 

分 类 号：P435[天文地球—大气科学及气象学]