Articles | Volume 10, issue 4
https://doi.org/10.5194/esurf-10-797-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esurf-10-797-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
02 Aug 2022
Research article |
| 02 Aug 2022
| 02 Aug 2022
Unraveling the hydrology and sediment balance of an ungauged lake in the Sudano-Sahelian region of West Africa using remote sensing
Silvan Ragettli
CORRESPONDING AUTHOR
hydrosolutions Ltd., Venusstrasse 29, 8050 Zurich, Switzerland
Tabea Donauer
hydrosolutions Ltd., Venusstrasse 29, 8050 Zurich, Switzerland
Institute of Environmental Engineering, ETH Zurich, Zurich, Switzerland
Peter Molnar
Institute of Environmental Engineering, ETH Zurich, Zurich, Switzerland
Ron Delnoije
Caritas Switzerland, Bamako, Mali
Tobias Siegfried
hydrosolutions Ltd., Venusstrasse 29, 8050 Zurich, Switzerland
Institute of Science, Technology and Policy, ETH Zurich, Zurich, Switzerland
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Landslides are a natural hazard that affects alpine regions. Here we focus on rainfall-induced shallow landslides and one of the most widely used approaches for their predictions: rainfall thresholds. We design several comparisons utilizing a landslide database and rainfall records in Switzerland. We find that using daily rather than hourly rainfall might be a better option in some circumstances, and mean annual precipitation and antecedent wetness can improve predictions at the regional scale.
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Short summary
This paper presents a novel methodology to identify and quantitatively analyze deposition and erosion patterns in ephemeral ponds or in perennial lakes with strong water level fluctuations. We apply this method to unravel the water and sediment balance of Lac Wégnia, a designated Ramsar site in Mali. The study can be a showcase for monitoring Sahelian lakes using remote sensing data, as it sheds light on the actual drivers of change in Sahelian lakes.
This paper presents a novel methodology to identify and quantitatively analyze deposition and...
