Sentinel-3 radar altimetry for river monitoring – a catchment-scale evaluation of satellite water surface elevation from Sentinel-3A and Sentinel-3B
| Autor: | Liguang Jiang, Christian Tøttrup, Cecile Marie Margaretha Kittel, Peter Bauer-Gottwein |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Synthetic aperture radar
010504 meteorology & atmospheric sciences 0208 environmental biotechnology Drainage basin 02 engineering and technology Structural basin 01 natural sciences lcsh:Technology lcsh:TD1-1066 SDG 13 - Climate Action Altimeter lcsh:Environmental technology. Sanitary engineering lcsh:Environmental sciences 0105 earth and related environmental sciences Remote sensing SDG 15 - Life on Land lcsh:GE1-350 geography geography.geographical_feature_category lcsh:T Mode (statistics) Elevation lcsh:Geography. Anthropology. Recreation 020801 environmental engineering lcsh:G Temporal resolution Environmental science Satellite |
| Zdroj: | Kittel, C M M, Jiang, L, Tøttrup, C & Bauer-Gottwein, P 2021, ' Sentinel-3 radar altimetry for river monitoring-A catchment-scale evaluation of satellite water surface elevation from Sentinel-3A and Sentinel-3B ', Hydrology and Earth System Sciences, vol. 25, no. 1, pp. 333-357 . https://doi.org/10.5194/hess-25-333-2021 Hydrology and Earth System Sciences, Vol 25, Pp 333-357 (2021) |
| ISSN: | 1607-7938 |
| DOI: | 10.5194/hess-25-333-2021 |
| Popis: | Sentinel-3 is the first satellite altimeter to operate in Synthetic Aperture Radar (SAR) mode and in open-loop tracking mode nearly globally. Both features are expected to improve the ability of the altimeters to observe inland water bodies. In this study we evaluate the possibility to extract river water surface elevation (WSE) at catchment level from Sentinel-3A and Sentinel-3B radar altimetry, using Level-1b and Level-2 data from two public platforms. The objectives of the study are to evaluate the density of valuable observations and establish a WSE monitoring network. Additionally, we demonstrate the potential application of Sentinel-3 for monitoring river interactions with wetlands and floodplains. In the Zambezi basin, 175 virtual stations (VS) contain useful WSE information in both datasets, far exceeding the number of VS available in standard databases. The RMSD is between 2.7 cm and 31.2 cm at six in-situ stations and the VS reflect the observed WSE climatology throughout the basin. Additional VS are available in both the Copernicus Open Access Hub and GPOD (Grid Processing on Demand), highlighting the value of considering multiple processing options. In particular, we show that the processing options available on GPOD strongly affect the number of useful VS; in particular, extending the size of the receiving window, considerably improved data at 13 Sentinel-3 VS. The number of VS delivering usable data increased after the Open-Loop Tracking Command (OLTC) on-board Sentinel-3A was updated. However, the open-loop tracking mode poses two new challenges: correct on-board elevation information is crucial, and steep changes in the receiving window position can have detrimental effects on the WSE observations. Finally, we extract Sentinel-3 observations over key wetlands in the Zambezi basin. We show that clear seasonal patterns are captured in the Sentinel-3 WSE, reflecting flooding events in the floodplains. These results highlight the potential of using Sentinel-3 as a SWOT (Surface Water and Ocean Topography) surrogate while awaiting the mission launch. The results show the benefit of the high-resolution Synthetic Aperture Radar (SAR) altimeter, as well as the benefits and disadvantages of the open-loop tracking mode. |
| Databáze: | OpenAIRE |
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