GPS掩星观测的发展及其在气象业务中的应用现状

摘要

GPS无线电掩星探测技术已经发展成为一种强有力的、相对经济的观测全球大气的方法.多年对GPS/MET概念卫星、CHAMP和SAC-C等GPS掩星观测的研究表明,GPS掩星观测资料与其他卫星资料相比具有很高的观测精度和垂直分辨率等优点,并且GPS掩星观测不受天气状况的影响,因此对其在天气预报及气候的应用有独特的优势.GPS无线电掩星探测技术的发展,特别是COSMIC/FORMOSAT-3(简称COSMIC)的成功发射,标志着GPS大气遥感观测进入了一个崭新的时代.正是在这样的背景下,文中首先对整个GPS卫星的历史发展及其观测特点进行一个总体性的回顾,然后考察了GPS掩星观测资料在天气预报研究中的应用问题,进一步详细地讨论了在数值天气预报中COSMIC掩星的业务资料同化.%The Global Position System (GPS) radio occultation technique has emerged as a powerful and relatively inexpensive approach to sounding the global atmosphere in all weathers.As demonstrated by the proof-of-concept GPS meteorology (GPS/ MET) experiment and more recently by the CHAMP and SAC-C missions, the GPS radio occultation (RO) sounding data are shown to be of high precision, accuracy and vertical resolution.On 15 April 2006, as the joint U.S.-Taiwan COSMIC/FORMOSAT-3 (hereafter COSMIC) mission, a constellation of six microsatellites was successfully launched, marking the beginning of a new era of GPS atmospheric remote sensing.Under this background, we review the objectives and status of the GPS satellite missions and present highlights of the GPS RO data applications to weather research.Especially we describe in detail the operational assimilation of COSMIC data in the numerical weather prediction models.