ABSTRACT

Atmospheric sensing by Global Navigation Satellite System (GNSS) signals has been exclusively studied for over two decades. This study derives the real-time Precipitable Water Vapour (PWV) by taking 1 month GNSS observation data from 11 stations. A Country-wide Pressure and Temperature (CPT) model is applied to precisely determine PWV from Zenith Tropospheric Delay (ZTD). It shows that the computed ZTD RMSE obtained from most stations is less than 15 mm, meeting a threshold of 15 mm input to its Numerical Weather Prediction (NWP) equation while the average RMSE of PWV is less than 3 mm; suitable for weather nowcasting.

摘要

全球导航卫星系统 (GNSS) 信号的大气传感已被专门研究了二十多年。本研究通过从 11 个站点获取 1 个月的 GNSS 观测数据，得出实时可降水量 (PWV)。应用全国范围的压力和温度 (CPT) 模型从天顶对流层延迟 (ZTD) 精确确定 PWV。它表明，从大多数台站计算得到的 ZTD RMSE 小于 15 mm，满足其数值天气预报（NWP）方程输入 15 mm 的阈值，而 PWV 的平均 RMSE 小于 3 mm；适用于临近天气预报。