陈雪娇,刘奇俊,马占山. 2021. GRAPES全球模式云方案的诊断研究[J]. 气象学报, 79(1):65-78, doi:10.11676/qxxb2020.066
GRAPES全球模式云方案的诊断研究
A diagnostic study of cloud scheme for the GRAPES global forecast model
投稿时间:2020-04-26  修订日期:2020-08-06
DOI:10.11676/qxxb2020.066
中文关键词:  GRAPES全球预报系统  云方案  诊断  评估
英文关键词:GRAPES_GFS  Cloud microphysics scheme  Diagnosis  Evaluation
基金项目:国家公益性行业(气象)科研专项(GYHY201506008)和国家重点研发计划项目(2018YFC1505702)
作者单位E-mail
陈雪娇 中国气象科学研究院, 北京, 100081  
刘奇俊 中国气象局国家气象中心, 北京, 100081 liuqj@cma.gov.cn 
马占山 中国气象局国家气象中心, 北京, 100081  
摘要点击次数: 82
全文下载次数: 62
中文摘要:
      在对GRAPES全球预报系统(GRAPES_GFS)云预报性能进行诊断评估的基础上,对凝结(华)和蒸发等物理过程及对流卷出对云的影响过程进行改进和优化,旨在提高GRAPES_GFS云量及其特征量和降水的预报精度。通过研究GRAPES全球模式、欧洲中期天气预报中心(ECMWF)和美国环境预报中心(NCEP)全球模式中3种云方案原理上的区别和联系,并将GRAPES_GFS预报结果与ECMWF第5代全球再分析资料(ERA5)做对比,分析云方案改进前后云量、云含水量、柱含水量等云宏观、微观物理量,降水量、向外长波辐射等基本物理量以及物理过程对温度和湿度的反馈倾向的预报性能,在此基础上对GRAPES_GFS原云方案进行改进。结果显示,云方案改进后,GRAPES_GFS在热带地区液水预报增大,云系和水成物垂直分布更合理;云量预报与ERA5预报结果更接近,特别是高云量预报的改进,使得热带向外长波辐射预报略有改进;低纬度地区日平均总降水量略有增大,特别是热带地区格点尺度降水增多较为明显,缓解了热带区域格点尺度降水预报偏小的现象。
英文摘要:
      The performance of the GRAPES Global Forecasting System (GRAPES_GFS) was diagnosed and evaluated by comparing its forecasts with the fifth-generation ECMWF global climate and atmospheric reanalysis data (ERA5), and the effects of convection on cloud microphysical processes such as condensation (sublimate) and evaporation were optimized. The research emphasizes: (1) Cloud macro and micro physical quantities, such as cloud cover, cloud water content, column cloud water content etc.; (2) precipitation and outgoing long-wave radiation (OLR); (3) the feedback tendency of different physical process for temperature and humidity. The results show that after the cloud scheme is improved, liquid-water content forecasted by the GRAPES_GFS has increased in tropical regions, and the vertical distribution of hydrometers becomes more reasonable. The cloud cover forecast is closer to the ERA5. Particularly, the model performance for high cloud forecast has been improved significantly, which subsequently improves the OLR forecast. Total forecast precipitation in tropical areas increases slightly, while large-scale precipitation increase in the tropical areas is more obvious, which alleviates the underestimation of large-scale precipitation in the tropical areas.
HTML   查看全文   查看/发表评论  下载PDF阅读器
分享按钮