结合激光雷达评估常规探空资料反演青藏高原混合层高度的适用性  

An Assessment with Lidar on the Applicability of Radiosonde Data in Retrieving the Mixing Height in Tibetan Plateau

作　　者：王存贵[1,2] 李成才[1] 贺千山[3] 檀望舒 初奕琦 李建[1] WANG Cungui;LI Chengcai;HE Qianshan;TAN Wangshu;CHU Yiqi;LI Jian(Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871;92914 PLA Troops, Lingao 571820;Shanghai Meteorological Service, Shanghai 201100)

机构地区：[1]北京大学物理学院大气与海洋科学系 [2]中国人民解放军92914部队 [3]上海市气象局

出　　处：《北京大学学报（自然科学版）》2017年第3期579-587,共9页Acta Scientiarum Naturalium Universitatis Pekinensis

基　　金：中国科学院战略性先导科技专项(XDA05040000);863计划(SQ2010AA1221583001);国家公益性行业(气象)科研专项(GYHY201406001;GYHY201106023);国家自然科学基金(41175020;41375008)资助

摘　　要：利用微脉冲激光雷达探测资料,采用梯度法获取那曲地区夏季的混合层高度序列及日最大混合层高度;利用每日两次(08:00和20:00)的探空资料结合地面最大位温,采用气块法得到雷达探测对应日期的日最大混合层高度(MMH)。通过对比从不同资料得到的MMH,发现08:00探空反演结果与激光雷达结果有较好的一致性(相关系数R为0.85,均方根误差RMSE为0.30 km,平均绝对误差MAE为0.25 km,并通过显著性水平为0.95的t检验);20:00探空反演结果则与激光雷达结果偏差相对较大(R为0.84,RMSE为0.67 km,MAE为0.54 km,未通过t检验)。分析产生偏差的原因发现,探空时刻的残余层、前期的天气变化过程以及对流泡活动或强卷夹过程引起的混合层高度时空变化等都可能是导致20:00高度结果与激光雷达结果不一致的原因,使得20:00探空资料不适合进行最大混合高度的反演。位温廓线的日变化特征也会影响反演结果的准确性,导致08:00探空结果偏高,但可以通过统计订正做修正。With micro-pulse lidar(MPL)data,the max mixing height(MMH)in the summer of Naqu is retrievedby gradient method.With radiosonde data(twice daily at08:00and20:00)and max potential temperature of Naquin the corresponding date,MMH is retrieved by parcel method.The intercomparison between MMHs from thedifferent data shows that the result from08:00radiosonde data consists well with MPL results,with correlationcoefficient0.85,root-mean-square error(RMSE)0.30km,mean absolute error(MAE)0.25km,and the t-test(0.95)passed.But the result from20:00radiosonde data has larger deviation from MPL results,with the correlationcoefficient0.84,RMSE0.67km,MAE0.54km and failed in the t-test.Deviation analysis shows that some factorssuch as the residual mixing layer in20:00soundings,some local weather process before the20:00launch time andthe temporal-spatial variation of the mixing height induced by the thermal convective bubbles or/and theentrainment process may cause the inconsistency in the results.All above lead to the non-availability of the20:00radiosonde data in retrieving the mixing height.The character of the diurnal variation of the potential temperatureprofile will also affect the accuracy of retrieval result,which would produce a higher height from08:00data,and some statistical corrections should be used to improve the result.

关 键 词：青藏高原 最大混合高度 微脉冲激光雷达 常规探空 

分 类 号：P407[天文地球—大气科学及气象学]