GPS掩星与探空观测统计比较中配对标准的比较研究

Research on the Collocation Criteria in the Statistical Comparisons of GPS Radio Occultation and Radiosonde Observations

在利用无线电探空数据对GPS掩星廓线进行验证的工作中,对如何确定两类观测资料在观测时间和空间上配对标准的问题进行了探讨。在观测时间差限值分别取1h、2h、3h,观测距离差限值分别取100km、200km、300km时得到的9种不同配对标准下,分别获取了GPS掩星与探空观测的折射指数廓线对,并进行了统计比较。结果表明,随着时间差限值与距离差限值的增大,总折射指数平均相对偏差的变化趋势性不强,但总折射指数平均相对标准偏差都呈增加趋势,且距离差限值变化的影响大于时间差限值的变化。

When verifying the precision of atmospheric parameter profiles obtained with GPS radio occultation （RO） technology with radiosonde observations, the collocation criterion should reasonable. The impacts of different collocation criterias on the statistical compari sons of GPS RO and radiosonde observations were studied. The time difference between the two types of observations are set to be 1 h, 2 h, and 3 h. The distance differences are set to be 100 km, 200 km, and 300 km, respectively. Different combinations of time differences and distance differences lead to 9 collocation criteria in total. Collocated GPS RO and radiosonde refractivity profiles are got and statistically compared with the 9 different collocation criterias, respectively. The results show that the variation of time differences and distance differences have little impact on the total refractivity mean relative deviation.