Evaluation of Water Level Estimation in the Upper Yangtze River from ICESat-2 Data

Abstract

The upper Yangtze River generally starts from the headwater region in the west and ends at Yichang (Hubei Province) in the east. Traditional techniques are difficult to monitor water level change in the upper Yangtze River at large scale. The Ice, Cloud and land Elevation Satellite-2 (ICESat-2) launched in September 2018, carrying a photon-counting laser altimeter, provides an opportunity for inland water level estimation. In this paper, the ATL13 global inland water data obtained from October 2018 to November 2020 were used to estimate the water level changes in the upper Yangtze River. The in-situ measurements of hydrometric stations were utilized to validate the estimated results. The results show that estimated the water levels from ICESat-2 are in good agreement with in-situ observations. The average water level estimation error is 0.27m, which shows that ICESat-2 laser altimetry data can monitor water level changes of the upper Yangtze River with a high accuracy.