Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.rsma.2024.103476
Licence creative commons licence
Title (Primary) Impacts of extreme river discharge on coastal dynamics and eEnvironment: Insights from high-resolution modeling in the German Bight
Author Nguyen, T.T.; Staneva, J.; Grayek, S.; Bonaduce, A.; Hagemann, S.; Pham, N.T.; Kumar, R. ORCID logo ; Rakovec, O. ORCID logo
Source Titel Regional Studies in Marine Science
Year 2024
Department CHS
Volume 73
Page From art. 103476
Language englisch
Topic T5 Future Landscapes
Supplements https://ars.els-cdn.com/content/image/1-s2.0-S2352485524001099-mmc1.docx
Keywords river freshwater discharge; sea surface salinity; German Bight; NEMO model; WAM model; GCOAST model; HD model; mHM model; coupled model
Abstract The intricate relationship between extreme river discharge and its consequential effects on coastal basins’ environment and dynamics remains a subject of profound significance. The impact of extreme river discharge on coastal basin dynamics and environment is a complex phenomenon, particularly relevant in the context of the German Bight. The inflow of freshwater from rivers into the German Bight plays a crucial role in driving the complex thermohaline circulation. Addressing the challenges posed by local hydro-meteorological extremes, compounded by strong wind waves, currents and tides is vital for comprehensive impact assessment. Utilizing the Geesthacht Coupled cOAstal model SysTem (GCOAST) with high-resolution configuration, we investigate the sensitivity of the thermohaline properties to the river forcings. By incorporating river discharge as lateral land forcing in a coupled hydrodynamic and wave model, we conducted five sensitivity experiments. Our findings reveal that the simulated temperatures closely match measurements in all experiments. The salinity, however, is remarkably sensitive to the variation of freshwater from the rivers Elbe and Ems in the German Bight, causing the haline stratification. The statistical evaluation, as demonstrated by the Taylor diagram at the Marnet DB station, underscores the skill of the Mesoscale Hydrologic Model (mHM) in generating the freshwater discharge that drives the thermohaline characteristics of the German Bight, especially during events like the June 2013 flooding. Significantly, the use of climatological runoff proves to be ineffective in simulating stratification during extreme flooding events. In essence, this investigation enhances our understanding of the pivotal role played by high-frequency river freshwater buoyancy. It emerges as a driving force behind salinity fluctuations during extreme floods, providing valuable insights into coastal dynamics within the German Bight.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=28926
Nguyen, T.T., Staneva, J., Grayek, S., Bonaduce, A., Hagemann, S., Pham, N.T., Kumar, R., Rakovec, O. (2024):
Impacts of extreme river discharge on coastal dynamics and eEnvironment: Insights from high-resolution modeling in the German Bight
Reg. Stud. Mar. Sci. 73 , art. 103476 10.1016/j.rsma.2024.103476