摘要
利用欧洲中期天气预报中心(ECMWF)第五代全球大气再分析资料ERA5,对2019年1月至2021年12月重庆沙坪坝TWP3型和酉阳TWP8-L(Ⅱ)型风廓线雷达风场数据进行评估分析。为了检验再分析资料ERA5在重庆的代表性,利用未被再分析资料同化的探空加密观测资料(2014—2016年每年6—8月)13时秒数据,对同时段的ERA5风场小时数据进行检验,发现两者平均偏差较小,表明ERA5再分析资料风场数据能够用于检验重庆风廓线雷达水平风的精度。同时,对比分析风廓线雷达与ERA5再分析资料。结果表明:低层水平风的相关系数低于中高层,但5000 m高度以下的差值为-1~1 m·s^(-1),且随着高度的上升,u分量差值表现出向负值增大,v分量差值向正值增大的分布趋势;高温少雨的夏季,风廓线测量的风场信息要优于冬季;降水天气会影响风廓线雷达的测风准确性。在低层,风廓线u分量在降水天气时的偏大幅度比无降水时稍强,而中高层上,降水天气对v分量的精度影响较为明显,v分量的偏小幅度比无降水时表现得要稍强;飑线天气过程中,在探测高度内,两种资料的风速大小较为接近,只是低层的u、v风场,风廓线较再分析资料略偏大。
The wind fields measured from the TWP3-type wind profile radar in Shapingba and the TWP8-L(Ⅱ)-type radar in Youyang of Chongqing,were assessed and analyzed towards the ERA5 reanalysis data.The dense radiosonde observations at 13:00 from June to August of 2014-2016,which have not been assimilated by the reanalysis,are firstly used to verify the representativeness of wind data from ERA5 reanalysis in Chongqing.It shows little deviation between them two,indicating the general reliability of the ERA5 reanalysis,which could further be employed to validate the accuracy of horizontal winds from Chongqing wind profile radars.The data from wind profile radar and ERA5 reanalysis were compared and analyzed.The results indicate that the correlation coefficient of horizontal winds at lower layers is lower than that at the middle and upper layers.However,the deviations mainly range from-1 to 1 m·s^(-1) at altitudes below 5000 m.With the increasing altitudes,the u-component deviations tend to increase negatively,while the v-component deviations increase positively.In the summer season with hotness and dryness,the wind field measured by wind profiles is more precise to that in winter.The accuracy of wind measurements from wind profile radars is affected by precipitation.At the lower layers,the stronger deviations of u-component from wind profiles tend to be slightly larger during precipitation processes than during non-precipitation periods.At the middle and upper layers,the accuracy of the v-component wind is significantly affected by precipitation,with its weaker deviations being slightly larger during precipitation processes than during non-precipitation periods.During squall line weather,the wind speeds detected by both datasets are relatively close,while the wind profile data show slightly larger u and v wind components at the lower layers compared to reanalysis data.
作者
赵美艳
朱君
余君
蒋镇
ZHAO Meiyan;ZHU Jun;YU Jun;JIANG Zhen(Chongqing Meteorological Information and Technical Support Center,Chongqing 401147,China;Fengdu Meteorological Service,Fengdu 408200,China;Yunyang Meteorological Service,Yunyang 404500,China)
出处
《气象与环境学报》
2024年第3期115-123,共9页
Journal of Meteorology and Environment
基金
重庆市气象部门业务技术攻关项目(YWJSGG-202215)资助。
