FY-4A云导风在GRAPES_RAFS中的同化应用评估  

The Evaluation of FY-4A AMVs in GRAPES_RAFS

作　　者：万晓敏 龚建东 韩威 田伟红 WAN Xiaomin;GONG Jiandong;HAN Wei;TIAN Weihong(National Meteorological Centre,Beijing 100081)

机构地区：[1]国家气象中心,北京100081

出　　处：《气象》2019年第4期458-468,共11页Meteorological Monthly

基　　金：GRAPES专项(GRAPES-FZZX-2018-05);公益性行业(气象)科研专项(GYHY201506002和GYHY201506022);国家气象中心青年基金(Q201705)共同资助

摘　　要：云导风资料具有较高的时空分辨率特性,是数值天气预报中重要的非常规观测资料之一。2016年12月我国第二代静止气象卫星风云四号首颗试验卫星(FY-4A)成功发射。依据国家卫星气象中心提供的2017年8月FY-4A卫星红外和高空、低空水汽通道云导风测试数据,选用美国国家环境预报中心的FNL全球分析资料为参考场,对比分析云导风资料观测分布及偏差特征。评估结果表明,FY-4A云导风测试数据分布稳定,水汽通道云导风资料观测数明显多于红外通道;红外通道云导风资料偏差和均方根误差最小,水汽通道云导风资料在高层偏差较大。基于GRAPES_RAFS系统,选取2017年第13号台风天鸽做24 h预报试验。个例试验结果表明,同化FY-4A云导风资料对模式高度场和风场分析有一定调整作用,特别是同化FY-4A水汽通道云导风资料,对强降水落区和强度预报有所改善。Atmospheric motion vectors(AMVs) can supply plenty of useful information for numerical weather prediction. With the launch of the Chinese next generation geostationary meteorological satellite FY-4 A in December 2016, it is necessary to evaluate the quality of FY-4 A AMVs for the analysis field and precipitation forecast by GRAPES of CM A. In this study, by comparing with the background field based on NCEP FNL data, the qualities of FY-4 A AMVs were assessed, and the results suggested that the distribution of FY-4 A is stable and the quality of FY-4 A infrared AMVs is better than FY-4 A water vapor AMVs. Based on GRAPES_RAFS, three numerical experiments were conducted to examine the impact on analysis and forecast for severe Typhoon Hato at 0000 UTC 23 August 2017. The findings showed that assimilating FY-4 A AMVs, especially FY-4 A water vapor AMVs, has certain adjusting effect on wind and height analysis fields. Furthermore,due to the improvement of the initial fields for the model prediction,the performance of the precipitaion forecast was improved. Conclusively, the FY-4 A AMVs have positive impact on analysis field and precipitation forecast of GRAPES.

关 键 词：FY-4A云导风资料 GRAPES数值模式 质量评估 资料同化 

分 类 号：P456[天文地球—大气科学及气象学] P413