2016年伊犁河谷大气可降水量变化特征及其与降水的关系  

Temporal Variation Characteristics of Precipitable Water Vapor Based on GPS Data and Its Relation with Precipitation at Yili River Valley in 2016

作　　者：刘晶[1,2] 周雅蔓 杨莲梅 张迎新[4] LIU Jing;ZHOU Yaman;YANG Lianmei;ZHANG Yingxin(Institute of Desert Meteorology,China Meteorological Administration,Urumqi 830002,China;Center for Central Asia Atmosphere Science Research,Urumqi 830002,China;Xinjiang Meteorological Obeservatory,Urumqi 830002,China;Beijing Meteorological Obeservatory,Beijing 100048,China)

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐830002 [2]中亚大气科学研究中心,新疆乌鲁木齐830002 [3]新疆气象台,新疆乌鲁木齐830002 [4]北京市气象台,北京100048

出　　处：《干旱气象》2019年第4期565-576,共12页Journal of Arid Meteorology

基　　金：中央级公益性科研院所基本科研业务费专项资金项目(IDM2016001);国家重点研发计划(2018YFC1507104);国家自然科学基金项目(41661144024)共同资助

摘　　要：利用NCEP/NCAR0.25°×0.25°再分析资料,ERA-Interim0.5°×0.5°再分析资料,2016年3月至2017年2月伊犁河谷3个地面观测站逐时和逐日降水及地基GPS大气可降水量(简称“PWV”),对各测站PWV时间变化及其与降水关系进行分析,明确了各站不同降水情况下及不同季节PWV的演变特征。结果表明:(1)各站PWV月际变化呈单峰型分布,谷值出现在1月,7月达到峰值,其中伊宁站2—9月(除7月)PWV与同期降水量变化一致,10—12月呈反向。(2)各站春、夏季平均PWV日变化曲线呈双峰型,春季各站峰值出现在17:00和00:00前后,较夏季峰值出现时间晚2~4h;秋季新源站PWV日变化曲线呈单峰型,其他两站PWV呈双峰型分布;冬季各站PWV日变化曲线均呈单峰型特征。随着测站海拔高度的增加,PWV日变化幅度逐渐增大。(3)PWV与降水有密切关系,PWV最大值出现时间超前降水0~3h、5h和7~9h发生频次最高,春、夏、秋、冬各季节降水分别主要发生在PWV最大值出现后0~3h、0~2h和5~7h、0~3h和7~9h及0~1h。不同降水情况下各站PWV值存在显著差异,海拔越高的测站差异越不显著。(4)降水发生前PWV增大与对流层低层水汽输送和水汽流入有关;降水期间不同影响系统、不同水汽输送造成的PWV增大时间和峰值有所不同,降水开始时间与PWV峰值有较好的对应关系。降水期间暴雨区水汽垂直输送明显,对流层中、高层云形成云冰水聚集区,PWV有明显跃变,存在水汽的快速聚集过程,造成测站短时强降水天气。Based on the NCEP/NCAR 0.25°×0.25°reanalysis data,ERA-Interim 0.5°×0.5°reanalysis data,hourly and daily precipitation data,ground-based GPS precipitable water vapor data(P WV)from March 2016 to February 2017 at three stations in the Yili River Valley,temporal variation characteristics of P WV and its relationship with precipitation at three stations were analyzed.The evolution characteristics of P WV at different stations under different precipitation conditions and in different seasons were clarified.The results were as follows:(1)P WV had an obvious monthly variation,and it presented single-peak distribution at each station with the lowest value in January and the peak in July.The variation of P WV at Yining station was in consistent with the precipitation change from February to September(except July)but it was opposite from October to December.(2)The diurnal variation of P WV at each station presented double-peak distribution in spring and summer,the maximum P WV appeared at 17:00 BST and 00:00 BST in spring,and it was 2-4 h later than that in summer.In autumn,the diurnal variation of P WV presented single peak distribution at Xinyuan station but it presented double peak distribution at other two stations,while diurnal variation of P WV at three stations presented single-peak distribution in winter.As the altitude of the station increased,the variation of daily P WV increased gradually.(3)The maximum P WV was 0-3 h,5 h,and 7-9 h ahead of precipitation,which was the highest frequency.The occurrence time of precipitation in four seasons mainly was 0-3 h,0-2 h and 5-7 h,0-3 h and 7-9 h,and 0-1 h later than that of the maximum P WV,respectively.There were significant differences for P WV values in three stations under different precipitation conditions,and the higher the altitude,the less significant the difference was.(4)Humidification of P WV was related to the transport and inflow of water vapor in the lower troposphere before rainfall occurrence.During the precipitation period,the peak value of P WV and

关 键 词：伊犁河谷 地基GPS 降水 大气可降水量 

分 类 号：P458.121.1[天文地球—大气科学及气象学]