广西地区加权平均温度模型建立及其精度评估

Establishment and Accuracy Evaluation of Weighted Average Temperature Model in Guangxi

加权平均温度(T_(m))是GNSS反演大气水汽中一个非常重要的转换参数。利用广西地区百色、桂林、梧州、南宁4个探空站连续15 a(2003-2017年)的实测数据,以数值积分法计算的T_(m)作为参考值,分析T_(m)与地面温度T_(s)、水气压e_(s)、纬度φ以及海拔高H之间的相关性,并基于最小二乘原理建立广西地区加权平均模型GXT_(m)。结果表明:T_(m)与地面温度T_(s)、水气压e_(s)呈正相关,与纬度φ、海拔高H呈负相关;加权平均温度模型GXT_(m)整体预测效果优于谢邵峰广西模型、姚宜斌模型以及Bevis全球模型,其精度比谢邵峰广西模型提高了8.4%,比姚宜斌模型提高了25.7%,比Bevis全球模型提高了28.4%。

Weighted average temperature(T_(m))is a very important conversion parameter in atmospheric water vapor retrieval by GNSS.Based on the measured data of Baise,Guilin,Wuzhou and Nanning sounding stations in Guangxi for 15 years(2003-2017),the correlation between T_(m) and surface temperature T_(s),water vapor pressure e_(s),latitude φ and elevation H is analyzed with the T_(m) calculated by numerical integration method as the reference value,and the weighted average model GXT_(m) in Guangxi is established based on the least square principle.The results show that:T_(m) is positively correlated with surface temperature T_(s),water vapor pressure e_(s),and negatively correlated with latitude φ and elevation H;the overall prediction effect of weighted average temperature model GXT_(m) is better than XIE Shaofeng Guangxi model,YAO Yibin model and Bevis global model,and its accuracy is 8.4% higher than XIE Shaofeng Guangxi model,25.7% higher than YAO Yibin model,and 28.4% higher than Bevis global model.