利用多模多频GNSS-IR信号反演沿海台风风暴潮

Abstract

台风风暴潮每年给沿海城市造成了极大的损失, 近年来利用GNSS反射信号的地基遥感方法可以用于潮位监测, 称为GNSS-IR（global navigation satellite system-interferometric reflectometry）, 对风暴潮期间验潮站资料进行补充。由于风暴潮发生时间短且破坏性强, 单系统GPS的时间分辨率难以满足海洋灾害的监测需求。本文基于中国香港站（HKQT）和巴哈马群岛站（BHMA）的多模多频GNSS卫星观测数据反演了3次沿海风暴潮事件。先对多模多频数据的质量进行分析, 随后分别对2019年飓风“多里安”、2018年台风“山竹”和2017年台风“天鸽”引起的3次风暴潮, 利用基于滑动窗口的最小二乘法对多模多频GNSS-IR反演结果进行改正并与验潮站实测值对比分析。试验结果表明, 利用多模多频GNSS-IR反演“多里安”风暴潮的精度优于14 cm, 反演“天鸽”和“山竹”风暴潮的精度优于9 cm。相比GPS单系统, 多模多频GNSS-IR能够提高监测的精度和时间分辨率, 有效提取风暴潮中异常潮位的涨潮、峰值和落潮的全过程, 对海洋灾害的研究监测发挥重要作用。

Alternate abstract:

Typhoon storm surges cause great losses to coastal cities every year. In recent years, a ground-based remote sensing technology using GNSS reflected signal has been proved to be able to monitor tidal level, called global navigation satellite system interferometric reflectometry (GNSS-IR), which can supplement the data of tide gauge. However, storm surges have strong destructiveness and occur quickly, the time resolution of GPS cannot meet the requirement to monitor this marine disaster. In this paper, three coastal storm surge events were monitored using the multi-mode and multi-frequency GNSS data of HKQT site in Hong Kong, China and BHMA site in Bahamas Islands. Firstly, we analyzed the quality of multiple system data. Then, multi-mode and multi-frequency GNSS-IR was used for monitoring three storm surges caused by hurricane "Dorian" in 2019, typhoon "Mangkhut" in 2018 and typhoon "Hato" in 2017.The sliding window least squares method was used to correct the results and compared with tide gauge observations. The experimental results showed that the accuracy of "Dorian" is better than 14 cm, and the accuracy of "Hato" and "Mangkhut" are both better than 9 cm. Compared with GPS, it could improve the accuracy and the time resolution of the results, which is helpful to record the whole process of tide rising, peak and falling in storm surge. And it can play an important role in the study of marine disasters.