长三角地区GNSS可降水量直接转换模型研究

为简化GNSS大气可降水量(PWV)的计算过程，提高GNSS-PWV实时解算效率，利用2017~2018年长三角地区7个GNSS测站数据，分析GNSS-PWV与对流层延迟(ZTD)、地面气温(T)、地面气压(P)之间的线性关系，通过线性拟合建立PWV直接转换区域模型。实验结果表明：1）PWV与ZTD、P和T之间具有良好的相关性，相关系数分别为0.99、-0.74和0.73；2）基于ZTD的全年单因子PWV模型的RMS为3.07 mm，基于ZTD和T的全年双因子PWV模型RMS为2.35 mm，基于ZTD和P的全年双因子PWV模型RMS为1.18 mm，基于ZTD、T和P的全年多因子PWV模型RMS为0.47 mm，基于ZTD、T和P的分季节多因子PWV模型的平均RMS为0.28 mm，后者预测精度略优。

Research on Direct Conversion Model of GNSS Precipitable Water Vapor in Yangtze River Delta Region

In order to simplify the calculation of GNSS precipitable water vapor(PWV) and improve its real-time calculating efficiency, we analyze the linear relationship between GNSS-PWV and tropospheric delay(ZTD), surface temperature(T) and atmospheric pressure(P) using the GNSS data from 7stations in the Yangtze River Delta during 2017-2018. The general PWV direct transformation regional model for the Yangtze River Delta is established using the linear fitting. The experimental results show that PWV has a good correlation with ZTD, P and T, and their correlation coefficients are 0.99, -0.74 and 0.73 respectively. The RMS of the yearly single-factor PWV model based on ZTD is 3.07 mm, the RMS of the yearly double-factor PWV model based on ZTD and T is 2.35 mm, the RMS of the yearly double-factor PWV model based on ZTD and P is 1.18 mm and the RMS of the yearly multi-factor PWV model based on ZTD, T and P is 0.47 mm. The average RMS of the seasonal multi-factor PWV models based on ZTD, T and P is 0.28 mm, which is slightly better than that of the yearly multi-factor PWV model.