SMuK 2023 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
UP: Fachverband Umweltphysik
UP 4: Aerosols & Hydrological Cycle
UP 4.5: Vortrag
Mittwoch, 22. März 2023, 15:00–15:15, MOL/0213
Sediment transport in Indian rivers high enough to impact satellite gravimetry — •Alexandra Klemme1, Thorsten Warneke1, Heinrich Bovensmann1, Matthias Weigelt2, Jürgen Müller2, Tim Rixen3, Justus Notholt1, and Claus Lämmerzahl4 — 1Institute of Environmental Physics, University of Bremen, Germany — 2Institute of Geodesy, Leibniz Universität Hannover, Germany — 3Leibniz Center for Tropical Marine Research, Bremen, Germany — 4Centre of Applied Space Technology and Microgravity, University of Bremen, Germany
Satellite gravimetry is used to study the global hydrological cycle. It is a key component in the investigation of groundwater depletion on the Indian subcontinent. Mass loss by sediment transport in rivers is assumed to be below the detection limit of current gravimetric satellites like GRACE-FO. Thus, it is not considered in the calculation of terrestrial water budgets from gravimetric data. However, the Indian subcontinent is drained by some of the world’s most sediment rich rivers and mass loss by sediment transport will impact long term gravimetric anomalies. We estimate the impact of sediment mass loss within different river catchments on gravimetric estimates of trends in terrestrial water storage. For the Ganges-Brahmaputra-Meghna catchment, our results indicate that sediment transport could account for (6±3) % of the gravity anomalies attributed to groundwater depletion. For erosion-prone Himalaya regions, we find an average sediment mass loss of 2 kg m−2 yr−1 which is almost 20 % of the observed gravity anomaly.