Retrieval of Vertical Distribution of Tropospheric Refractivity through Ground-Based GPS Observation

作     者：WU Xue WANG Xin L Daren 

作者机构：Key Laboratory for Atmosphere and Global Environment ObservationInstitute of Atmospheric Physics Chinese Academy of Sciences University of the Chinese Academy of Sciences 

出 版 物：《Advances in Atmospheric Sciences》 (大气科学进展（英文版）)

年 卷 期：2014年第31卷第1期

页      面：37-47页

核心收录：

学科分类：07[理学] 070601[理学-气象学] 0706[理学-大气科学] 0816[工学-测绘科学与技术] 0825[工学-航空宇航科学与技术] 

基　　金：supported by the National Basic Research Program of China (973 Program) under Grant No. 2010CB428601 the Open Fund of the State Key Laboratory of Satellite Ocean Environment Dynamics under Contract No. SOED0705 the China Postdoctoral Science Foundation 

主　　题：Global Positioning System (GPS) refractivity atmospheric delay ray-tracing exhaustive search 

摘      要：In the present reported study, the vertical distributions of local atmospheric refractivity were retrieved from ground- based GPS observations at low elevation angles. An improved optimization method was implemented at altitudes of 0-10 km to search for a best-fit refractivity profile that resulted in atmospheric delays most similar to the delays calculated from the observations. A ray-tracing model was used to simulate neutral atmospheric delays corresponding to a given refractivity profile. We initially performed a ＂theoretical retrieval＂, in which no observation data were involved, to verify the optimization method. A statistical relative error of this ＂theoretical retrieval＂ （-2% to 2%） indicated that such a retrieval is effective. In a practical retrieval, observations were obtained using a dual-frequency GPS receiver, and its initial value was provided by CIRA86aQ_UoG data. The statistical relative errors of the practical retrieval range from -3% to 5% were compared with co-located radiosonde measurements, Results clearly revealed diurnal variations in local refractivity prc,files, The results also suggest that the general vertical distribution of refractivity can be derived with a high temporal resolution. However, further study is needed to describe the vertical refractivity gradient clearly.