应用地基GPS技术遥感大气柱水汽量的试验研究
TEST AND STUDY OF THE EARTH-BASED GPS TECHNIQUE FOR REMOTE SENSING OF ATMOSPHERIC PRECIPITABLE WATER
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摘要: 从理论上分析了AN (Aske and Nordius) 大气柱总水汽量 (W) 计算模型的偏差, 探空试验结果证实了理论分析的结论.作者经过推导, 建立了新的W计算模型, 与探空方法获得的W值具有很好的一致性. 1998年进行了一次“GPS暴雨观测试验”.试验结果发现:可降雨量的高值时段与降雨过程高度相关; 大的降雨过程, 在降雨前, 可降雨量一般都有一段递增过程, 在降雨结束过程中, 可降雨量一般都有一个递减过程, 在突发暴雨事件发生前往往发生可降雨量突然大幅度递增现象; 在大暴雨事件发生前, 存在一个长时间的十分明显的孕育阶段.Abstract: The deviation of AN (Askne and Nordius) model for calculating PW value has been analyzed theoretically and the conclusion drawn from the theoretical analysis has been confirmed by the results from the sounding test. Through the derivation, a new precipitable Water (PW) calculation model has been established and the calculated results are well consists with the PW values obtained by the sounding method. In 1998, a "GPS Storm Observation Test" was car ried out. It has been discovered from the test results that the high-value time interval of PW generally has an increasing period before the rainfall and a decreasing period in the process when the rainfall is ended; before the occurrence of a sudden storm event, unexpected large-scale increase of PW often occurs; before the occurrence of a large storm event, there is a very clear pregnancy period lasting for a long time.
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Key words:
- Water vapor remote sensing;
- Ground-based GPS;
- Rainfall experiment;
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表 1 可降雨量计算结果统计
表 2 1998年5~6月份W值统计表
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[1] Askne J, Nordius H.Estimation of tropospheric delay for microwaves from surface weather data.Radio Sci., 1987, 22:379~386. doi: 10.1029/RS022i003p00379 [2] Bevis M S, Businger T, Anther A, et al.GPS meteorology:Remote sensing of atmospheric water vapor using the global positioning system.J.Geophys.Res., 1992, 97:15787~15801. doi: 10.1029/92JD01517 [3] Boudouris G.The index of refraction of air, absorption and dispersion of centimeter waves by gases.J.Res.Natl.Bur.Stand., 67D, 1963, 631~684. [4] Davis J L, Herring T A, Shapiro I I, et al.Geodesy by radio interferometry:Effects of atmospheric modeling errors on estimates of bas eline length.Radio Sci., 1985, 20:1593~1607. doi: 10.1029/RS020i006p01593