FY-2C卫星大气运动矢量产品的高度指定误差分析  

Errors in height assignment for atmospheric motion vectors of FY-2C

作　　者：杨成荫[1] 陆其峰[2] 吴雪宝[2] 张鹏[2] 

机构地区：[1]解放军理工大学气象学院,江苏南京211101 [2]国家卫星气象中心,北京100081

出　　处：《红外与毫米波学报》2012年第1期73-79,共7页Journal of Infrared and Millimeter Waves

基　　金：国家自然科学基金项目(40705037)~~

摘　　要：统计分析了2009年FY-2C水汽通道反演的AMVs(大气运动矢量)误差分布特征,结果显示,AMVs反演偏差存在气候带、季节以及垂直分布不均匀的时空特征.根据风随高度变化原理,推断高度指定偏高是主要误差来源.利用NCEP/FNL风场作参考,对AMVs进行高度再指定,进一步验证高度指定偏差是否为AMVs主要误差来源,结果表明,AMVs纬向风的负偏差明显减小,由-9.73 ms-1减小到-1.1 ms-1,误差标准差由10.24 ms-1降低到4.5ms-1,改善幅度超过50%,经向风的质量也有明显改善,较好地消除了季节性误差,佐证了前述观点.初步建议了一种利用数值预报分析场作为参考将AMVs高度指定到合理高度的方法,也为AMVs产品生产者提供了一个检验算法的思路.The quality and error distribution of atmospheric motion vectors（AMVs） derived from the water vapor band of FY-2C meteorological satelite of China in 2009 were analysed.The results indicate that the errors of AMVs varies inhomogeneously in different climate zones,seasons,and vertical positions in space.Based on the thermal wind theory,we noticed that over estimation in the value of height may be the dominant origin of the AMVs errors.We verified the conjecture by reassigning the AMVs to new heights,with the NCEP/FNL reanalysis wind field as a reference.The quality of AMVs before and after reassignment was compared with the NCEP/FNL data and radiosonde observations of international exchange stations.It＇s found that the negative biases of the U-winds of AMVs decrease explicitly from-9.73 ms-1 to-1.1 ms-1,the standard deviations of errors from 10.24 ms-1 to 4.5 ms-1,the quality of which is improved over 50%.The V-winds are also improved obviously.The seasonal errors of AMVs are removed well.All of the improvements justify the aforementioned viewpoints.This paper suggests a preliminary method which assigns the AMVs to reasonable heights with the reanalysed wind field of a NWP model as a reference,and also supplies an idea of detecting algorithm for AMVs producers.

关 键 词：卫星气象学 高度指定误差 误差分析 大气运动矢量 高度再指定 质量控制 

分 类 号：P414.4[天文地球—大气科学及气象学]