随着GPS全球定位系统的发展,已经有可能使用GPS掩星技术反演精确的大气温度,压强和湿度剖面.在概要地描述上海天文台(SHAO)开发的GPS掩星数据资料反演地球大气流程模块以后,分析了2002年8月1日至2002年8月17日期间2700多次CHAMP掩星数据资料的结果,并且与欧洲中尺度天气预报分析(ECMWF)资料进行比较和统计分析,讨论了CHAMP掩星数据的质量,并分析了CHAMP掩星数据的观测误差和ECMWF的分析模型误差.提出了一种优化的统计分析方法,它能更客观地反映GPS掩星技术的外部符合.统计分析结果表明GPS掩星数据将有可能成为数值天气预报和长期监测地球气候的非常有价值的数据资料.
With the development of the GPS satellite network, an opportunity now exists to acquire valuable precise temperature, pressure, and humidity data using radio occultation. It gives an overview of the Radio Occultation Data Processing in Shanghai Astronomical Observatory (SHAO). More than 2,700 CHAMP neutral atmosphere soundings were processed at SHAO in the period August 1st, 2002 to August 17th, 2002. The retrieved atmospheric profiles from CHAMP data were compared with the European Centre for Medium-range Weather Forecasts (ECMWF) analysis data. It also presents the statistic and analysis results by the comparisons among these datasets, and discusses the data quality of CHAMP radio occultation data. The computational results fairly indicate the potential of GPS occultation data which might become an extremely valuable data source for the numerical weather prediction (NWP) and long-term monitoring of the earth's climate.