AREM及其对2003年汛期降水的模拟

AREM AND ITS SIMULATIONS ON THE DAILY RAINFALL IN SUMMER IN 2003

  • 摘要: 文中回顾了一个能考虑陡峭复杂地形的有限区域η坐标数值预报模式(Regional Eta-coordinate Model,简称REM)十几年来的发展和应用过程,列举了该模式系统在气象、水文、环境和军事保障等科研和业务单位的主要应用。同时介绍了在此基础上发展升级的暴雨数值预报模式(Advanced REM,简称AREM)。由于(A)REM抓住了中国区域的地形和天气特点,已成为模拟和预报中国天气和环境灾害的重要工具,在环境治理、抗洪抢险、防灾减灾以及军事气象保障中发挥了重要作用。通过分析新版本AREM对2003年夏季中国东部区域降水过程的模拟和预报结果,反映了AREM对中国东部区域降水的模拟和预报能力,再现了2003年夏季中国东部主要降水过程的雨量分布和演变特征。ARM对主要降水区域平均降水量的逐日预报与观测基本一致。它不仅对发生在淮河流域的较大范围的降水预报如此,而且对有些受地形强迫影响的局部强降水中心,预报结果也与观测基本一致。

     

    Abstract: Facing significant effects of the Tibetan Plateau and many other steep mountains on the weather,especially on the precipitation in China,a regional Eta-coodinate model (REM) has been developed since 1980s and the REM has been popularly used not only to the summer precipitation predictions and the heavy rainfall studies butalso to related simulation studies in hydrology and environment in China since 1990s.According to distincta-tmospheric circulation and complex terrain features in China and learning from the current state-of-art smodels,such as,NCEP Etamodel,MM5,AR PS,IAP-model,CMAHLAFS,et al.,REM was paid muchattention on handling topography,moisture advection and minimizing artificial diffusion.Because of well handling with topography and water vapor trans-portation,the REM has shown it sgreat capabilities in capturing major features of precipitation in the Eastern China,including the distribution of summer rain belt,heavy rainfall intensity and maximum rainfall location.Based on the REM sframework,anadvanced REM (AREM) has been developing under cooperation with other institutes in recent years,which includes increasing resolut ions in vertical and horizontal and updating physical parameterizations.The horizontal resolution could reach about 18 km.In the vertical,the model could be unevenly divided into 32 layers.The main physical process in A REM consists:(1) explicit prediction scheme in cloud and precipitation;(2) modified Betts convective adjustment scheme;(3) nolocal PBL paramet erization scheme;(4) a two-step shapepreserving moisture advection scheme.Inaddition,from REM to AREM,many attentions are paid to the coding standardization and modularization.The preliminary version of AREM has beingused to study and predict the heavy rainfalls along the Yangtze River reaches.Realtime used predict ions in Hunan,Hubei and Anhui provinces in recent years show the great capabilities of AREM in forecasting the heavy rainfall events over most of China region.Case studies show that the AREM captures reasonable structures and evolutions of the rainfall systems along the Yangtze River.In this study,the capability of the AREM in predicting summer precipitation features over the Eastern China was shown by reproducing the summer rainfall from June 1 to August 30 in 2003.The AREM captures well notonly the southnorth movement of rainbelt,butalso the mean precipitation dist ribution and rainfall centers,in the summer of 2003.

     

/

返回文章
返回