Articles | Volume 18, issue 6
https://doi.org/10.5194/os-18-1725-2022
© 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/os-18-1725-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 Dec 2022
Research article |
| 12 Dec 2022
| 12 Dec 2022
Modelling the impact of anthropogenic measures on saltwater intrusion in the Weser estuary
Pia Kolb
CORRESPONDING AUTHOR
Federal Waterways Engineering and Research Institute, Wedeler
Landstraße 157, 22559 Hamburg, Germany
Anna Zorndt
Federal Waterways Engineering and Research Institute, Wedeler
Landstraße 157, 22559 Hamburg, Germany
Hans Burchard
Leibniz Institute for Baltic Sea Research Warnemünde,
Seestraße 15, 18119 Rostock, Germany
Ulf Gräwe
Leibniz Institute for Baltic Sea Research Warnemünde,
Seestraße 15, 18119 Rostock, Germany
Frank Kösters
Federal Waterways Engineering and Research Institute, Wedeler
Landstraße 157, 22559 Hamburg, Germany
Related authors
No articles found.
Robert Lepper, Leon Jänicke, Ingo Hache, Christian Jordan, and Frank Kösters
Ocean Sci., 20, 711–723, https://doi.org/10.5194/os-20-711-2024, https://doi.org/10.5194/os-20-711-2024, 2024
Short summary
Short summary
Most coastal environments are sheltered by tidal flats and salt marshes. These habitats are threatened from drowning under sea level rise. Contrary to expectation, recent analyses in the Wadden Sea showed that tidal flats can accrete faster than sea level rise. We found that this phenomenon was facilitated by the nonlinear link between tidal characteristics and coastal bathymetry evolution. This link caused local and regional tidal adaptation with sharp increase–decrease edges at the coast.
Torsten Kanzow, Angelika Humbert, Thomas Mölg, Mirko Scheinert, Matthias Braun, Hans Burchard, Francesca Doglioni, Philipp Hochreuther, Martin Horwath, Oliver Huhn, Jürgen Kusche, Erik Loebel, Katrina Lutz, Ben Marzeion, Rebecca McPherson, Mahdi Mohammadi-Aragh, Marco Möller, Carolyne Pickler, Markus Reinert, Monika Rhein, Martin Rückamp, Janin Schaffer, Muhammad Shafeeque, Sophie Stolzenberger, Ralph Timmermann, Jenny Turton, Claudia Wekerle, and Ole Zeising
EGUsphere, https://doi.org/10.5194/egusphere-2024-757, https://doi.org/10.5194/egusphere-2024-757, 2024
Short summary
Short summary
The Greenland Ice Sheet represents the second-largest contributor to global sea-level rise. We quantify atmosphere, ice and ocean-based processes related to the mass balance of glaciers in Northeast Greenland, focusing on Greenland’s largest floating ice tongue, the 79N Glacier. We find that together, the different in situ and remote sensing observations and model simulations to reveal a consistent picture of a coupled atmosphere-ice sheet-ocean system, that has entered a phase of major change.
Marvin Lorenz and Ulf Gräwe
Ocean Sci., 19, 1753–1771, https://doi.org/10.5194/os-19-1753-2023, https://doi.org/10.5194/os-19-1753-2023, 2023
Short summary
Short summary
We study the variability of extreme sea levels in a 13 member hindcast ensemble for the Baltic Sea. The ensemble mean shows good agreement with observations regarding return levels and trends. However, we find great variability and uncertainty within the ensemble. We argue that the variability of storms in the atmospheric data directly translates into the variability of the return levels. These results highlight the need for large regional ensembles to minimise uncertainties.
Joshua Kiesel, Marvin Lorenz, Marcel König, Ulf Gräwe, and Athanasios T. Vafeidis
Nat. Hazards Earth Syst. Sci., 23, 2961–2985, https://doi.org/10.5194/nhess-23-2961-2023, https://doi.org/10.5194/nhess-23-2961-2023, 2023
Short summary
Short summary
Among the Baltic Sea littoral states, Germany is anticipated to experience considerable damage as a result of increased coastal flooding due to sea-level rise (SLR). Here we apply a new modelling framework to simulate how flooding along the German Baltic Sea coast may change until 2100 if dikes are not upgraded. We find that the study region is highly exposed to flooding, and we emphasise the importance of current plans to update coastal protection in the future.
Bronwyn E. Cahill, Piotr Kowalczuk, Lena Kritten, Ulf Gräwe, John Wilkin, and Jürgen Fischer
Biogeosciences, 20, 2743–2768, https://doi.org/10.5194/bg-20-2743-2023, https://doi.org/10.5194/bg-20-2743-2023, 2023
Short summary
Short summary
We quantify the impact of optically significant water constituents on surface heating rates and thermal energy fluxes in the western Baltic Sea. During productive months in 2018 (April to September) we found that the combined effect of coloured
dissolved organic matter and particulate absorption contributes to sea surface heating of between 0.4 and 0.9 K m−1 d−1 and a mean loss of heat (ca. 5 W m−2) from the sea to the atmosphere. This may be important for regional heat balance budgets.
Matthias Gröger, Manja Placke, H. E. Markus Meier, Florian Börgel, Sandra-Esther Brunnabend, Cyril Dutheil, Ulf Gräwe, Magnus Hieronymus, Thomas Neumann, Hagen Radtke, Semjon Schimanke, Jian Su, and Germo Väli
Geosci. Model Dev., 15, 8613–8638, https://doi.org/10.5194/gmd-15-8613-2022, https://doi.org/10.5194/gmd-15-8613-2022, 2022
Short summary
Short summary
Comparisons of oceanographic climate data from different models often suffer from different model setups, forcing fields, and output of variables. This paper provides a protocol to harmonize these elements to set up multidecadal simulations for the Baltic Sea, a marginal sea in Europe. First results are shown from six different model simulations from four different model platforms. Topical studies for upwelling, marine heat waves, and stratification are also assessed.
Vera Fofonova, Tuomas Kärnä, Knut Klingbeil, Alexey Androsov, Ivan Kuznetsov, Dmitry Sidorenko, Sergey Danilov, Hans Burchard, and Karen Helen Wiltshire
Geosci. Model Dev., 14, 6945–6975, https://doi.org/10.5194/gmd-14-6945-2021, https://doi.org/10.5194/gmd-14-6945-2021, 2021
Short summary
Short summary
We present a test case of river plume spreading to evaluate coastal ocean models. Our test case reveals the level of numerical mixing (due to parameterizations used and numerical treatment of processes in the model) and the ability of models to reproduce complex dynamics. The major result of our comparative study is that accuracy in reproducing the analytical solution depends less on the type of applied model architecture or numerical grid than it does on the type of advection scheme.
Jens Daniel Müller, Bernd Schneider, Ulf Gräwe, Peer Fietzek, Marcus Bo Wallin, Anna Rutgersson, Norbert Wasmund, Siegfried Krüger, and Gregor Rehder
Biogeosciences, 18, 4889–4917, https://doi.org/10.5194/bg-18-4889-2021, https://doi.org/10.5194/bg-18-4889-2021, 2021
Short summary
Short summary
Based on profiling pCO2 measurements from a field campaign, we quantify the biomass production of a cyanobacteria bloom in the Baltic Sea, the export of which would foster deep water deoxygenation. We further demonstrate how this biomass production can be accurately reconstructed from long-term surface measurements made on cargo vessels in combination with modelled temperature profiles. This approach enables a better understanding of a severe concern for the Baltic’s good environmental status.
Qing Li, Jorn Bruggeman, Hans Burchard, Knut Klingbeil, Lars Umlauf, and Karsten Bolding
Geosci. Model Dev., 14, 4261–4282, https://doi.org/10.5194/gmd-14-4261-2021, https://doi.org/10.5194/gmd-14-4261-2021, 2021
Short summary
Short summary
Different ocean vertical mixing schemes are usually developed in different modeling framework, making the comparison across such schemes difficult. Here, we develop a consistent framework for testing, comparing, and applying different ocean mixing schemes by integrating CVMix into GOTM, which also extends the capability of GOTM towards including the effects of ocean surface waves. A suite of test cases and toolsets for developing and evaluating ocean mixing schemes is also described.
Robert Hagen, Andreas Plüß, Romina Ihde, Janina Freund, Norman Dreier, Edgar Nehlsen, Nico Schrage, Peter Fröhle, and Frank Kösters
Earth Syst. Sci. Data, 13, 2573–2594, https://doi.org/10.5194/essd-13-2573-2021, https://doi.org/10.5194/essd-13-2573-2021, 2021
Short summary
Short summary
We established an open-access, integrated marine data collection for 1996 to 2015 in the German Bight as a database of scientific, economic, and governmental interest. This paper presents data for tidal elevation, depth-averaged current velocity, bottom shear stress, depth-averaged salinity, and wave parameters and spectra at a high temporal and spatial resolution. Data are additionally processed into meaningful parameters (i.e., tidal characteristic values, e.g., tidal range) for accessibility.
Erik Jacobs, Henry C. Bittig, Ulf Gräwe, Carolyn A. Graves, Michael Glockzin, Jens D. Müller, Bernd Schneider, and Gregor Rehder
Biogeosciences, 18, 2679–2709, https://doi.org/10.5194/bg-18-2679-2021, https://doi.org/10.5194/bg-18-2679-2021, 2021
Short summary
Short summary
We use a unique data set of 8 years of continuous carbon dioxide (CO2) and methane (CH4) surface water measurements from a commercial ferry to study upwelling in the Baltic Sea. Its seasonality and regional and interannual variability are examined. Strong upwelling events drastically increase local surface CO2 and CH4 levels and are mostly detected in late summer after long periods of impaired mixing. We introduce an extrapolation method to estimate regional upwelling-induced trace gas fluxes.
Robert Daniel Osinski, Kristina Enders, Ulf Gräwe, Knut Klingbeil, and Hagen Radtke
Ocean Sci., 16, 1491–1507, https://doi.org/10.5194/os-16-1491-2020, https://doi.org/10.5194/os-16-1491-2020, 2020
Short summary
Short summary
This study investigates the impact of the uncertainty in atmospheric data of a storm event on the transport of microplastics and sediments. The model chain includes the WRF atmospheric model, the WAVEWATCH III® wave model, and the GETM regional ocean model as well as a sediment transport model based on the FABM framework. An ensemble approach based on stochastic perturbations of the WRF model is used. We found a strong impact of atmospheric uncertainty on the amount of transported material.
Hagen Radtke, Sandra-Esther Brunnabend, Ulf Gräwe, and H. E. Markus Meier
Clim. Past, 16, 1617–1642, https://doi.org/10.5194/cp-16-1617-2020, https://doi.org/10.5194/cp-16-1617-2020, 2020
Short summary
Short summary
During the last century, salinity in the Baltic Sea showed a multidecadal oscillation with a period of 30 years. Using a numerical circulation model and wavelet coherence analysis, we demonstrate that this variation has at least two possible causes. One driver is river runoff which shows a 30-year variation. The second one is a variation in the frequency of strong inflows of saline water across Darss Sill which also contains a pronounced 30-year period.
Marvin Lorenz, Knut Klingbeil, Parker MacCready, and Hans Burchard
Ocean Sci., 15, 601–614, https://doi.org/10.5194/os-15-601-2019, https://doi.org/10.5194/os-15-601-2019, 2019
Short summary
Short summary
Estuaries are areas where riverine and oceanic waters meet and mix. The exchange flow of an estuary describes the water properties of the inflowing and outflowing water. These can be described by simple bulk values for volume fluxes and salinities. This work focuses on the numerics of one computational method for these values, the Total Exchange Flow. We show that only the so-called dividing salinity method is able to reliably calculate the correct values, even for complex situations.
Beate Stawiarski, Stefan Otto, Volker Thiel, Ulf Gräwe, Natalie Loick-Wilde, Anna K. Wittenborn, Stefan Schloemer, Janine Wäge, Gregor Rehder, Matthias Labrenz, Norbert Wasmund, and Oliver Schmale
Biogeosciences, 16, 1–16, https://doi.org/10.5194/bg-16-1-2019, https://doi.org/10.5194/bg-16-1-2019, 2019
Short summary
Short summary
The understanding of surface water methane production in the world oceans is still poor. By combining field studies and incubation experiments, our investigations suggest that zooplankton contributes to subthermocline methane enrichments in the central Baltic Sea by methane production within the digestive tract of copepods and/or by methane production through release of methane precursor substances into the surrounding water, followed by microbial degradation to methane.
Carsten Lemmen, Richard Hofmeister, Knut Klingbeil, M. Hassan Nasermoaddeli, Onur Kerimoglu, Hans Burchard, Frank Kösters, and Kai W. Wirtz
Geosci. Model Dev., 11, 915–935, https://doi.org/10.5194/gmd-11-915-2018, https://doi.org/10.5194/gmd-11-915-2018, 2018
Short summary
Short summary
To describe coasts in a computer model, many processes have to be represented, from the air to the water to the ocean floor, from different scientific disciplines. No existing computer model adequately addresses this complexity. We present the Modular System for Shelves and Coasts (MOSSCO), which embraces this diversity and flexibly connects several tens of individual process models. MOSSCO also makes it easier to bring local knowledge to the Earth system level.
Joeran Maerz, Richard Hofmeister, Eefke M. van der Lee, Ulf Gräwe, Rolf Riethmüller, and Kai W. Wirtz
Biogeosciences, 13, 4863–4876, https://doi.org/10.5194/bg-13-4863-2016, https://doi.org/10.5194/bg-13-4863-2016, 2016
Short summary
Short summary
We investigated sinking velocity (ws) of suspended particulate matter (SPM) in the German Bight. By inferring ws indirectly from an extensive turbidity data set and hydrodynamic model results, we found enhanced ws in a coastal transition zone. Combined with known residual circulation patterns, this led to a new conceptual understanding of the retention of fine minerals and nutrients in shallow coastal areas. The retention is likely modulated by algal excretions enhancing flocculation of SPM.
Rahel Vortmeyer-Kley, Ulf Gräwe, and Ulrike Feudel
Nonlin. Processes Geophys., 23, 159–173, https://doi.org/10.5194/npg-23-159-2016, https://doi.org/10.5194/npg-23-159-2016, 2016
Short summary
Short summary
Since eddies play a major role in the dynamics of oceanic flows, it is of great interest to gain information about their tracks, lifetimes and shapes. We develop an eddy tracking tool based on structures in the flow with collecting (attracting) or separating (repelling) properties. In test cases mimicking oceanic flows it yields eddy lifetimes close to the analytical ones. It even provides a detailed view of the dynamics that can be useful to gain more insight into eddy dynamics in oceanic flows.
M. Duran-Matute, T. Gerkema, G. J. de Boer, J. J. Nauw, and U. Gräwe
Ocean Sci., 10, 611–632, https://doi.org/10.5194/os-10-611-2014, https://doi.org/10.5194/os-10-611-2014, 2014
A. Plüß and F. Kösters
Adv. Geosci., 39, 61–68, https://doi.org/10.5194/adgeo-39-61-2014, https://doi.org/10.5194/adgeo-39-61-2014, 2014
Related subject area
Approach: Numerical Models | Properties and processes: Tides | Depth range: Estuaries | Geographical range: Shelf Seas | Challenges: Other
A tidally driven fjord-like strait close to an amphidromic region
Sissal Vágsheyg Erenbjerg, Jon Albretsen, Knud Simonsen, Erna Lava Olsen, Eigil Kaas, and Bogi Hansen
Ocean Sci., 17, 1639–1655, https://doi.org/10.5194/os-17-1639-2021, https://doi.org/10.5194/os-17-1639-2021, 2021
Short summary
Short summary
Here, we describe a strait that has narrow and shallow sills in both ends and is close to an amphidromic region. This generates tidally driven flows into and out of the strait, but with very different exchange rates across the entrances in both ends so that it behaves like a mixture between a strait and a fjord. Using a numerical model, we find a fortnightly signal in the net transport through the strait, generated by long-period tides. Our findings are verified by observations.
Cited articles
Andrews, S. W., Gross, E. S., and Hutton, P. H.: Modeling salt intrusion in
the San Francisco Estuary prior to anthropogenic influence, Cont.
Shelf Res., 146, 58–81, https://doi.org/10.1016/j.csr.2017.07.010,
2017.
BAW: Mathematical Module SediMorph: Validation Document Version 1.1,
Hamburg, https://wiki.baw.de/de/index.php/Mathematisches_Verfahren_SEDIMORPH (last access: 2 December 2022), 2005.
BAW: Historical digital terrain model data of the Weser Estuary (HIWEST),
B3955.02.04.70168-6, Federal Waterways Engineering and Research Institute [data set],
https://doi.org/10.48437/02.2020.K2.5200.0001, 2020.
BAW: Historical digital terrain models of the Weser Estuary (HIWEST).
Technical Report B3955.02.04.70168-6, Federal Waterways Engineering and
Research Institute, https://hdl.handle.net/20.500.11970/107521 (last access: 2 December 2022), 2021.
Becherer, J., Flöser, G., Umlauf, L., and Burchard, H.: Estuarine
circulation versus tidal pumping: Sediment transport in a well-mixed tidal
inlet, J. Geophys. Res.-Oceans, 121, 6251–6270,
https://doi.org/10.1002/2016JC011640, 2016.
Burchard, H., Hetland, R. D., Schulz, E., and Schuttelaars, H. M.: Drivers
of Residual Estuarine Circulation in Tidally Energetic Estuaries: Straight
and Irrotational Channels with Parabolic Cross Section, J. Phys. Oceanogr.,
41, 548–570, https://doi.org/10.1175/2010JPO4453.1, 2011.
Burchard, H., Schulz, E., and Schuttelaars, H. M.: Impact of estuarine
convergence on residual circulation in tidally energetic estuaries and
inlets, Geophys. Res. Lett., 41, 913–919,
https://doi.org/10.1002/2013GL058494, 2014.
Burchard, H., Schuttelaars, H. M., and Ralston, D. K.: Sediment Trapping in
Estuaries, Annu. Rev. Mar. Sci., 10, 371–395,
https://doi.org/10.1146/annurev-marine-010816-060535, 2018.
Casulli, V.: A high-resolution wetting and drying algorithm for free-surface
hydrodynamics, Int. J. Numer. Meth. Fl., 60, 391–408,
https://doi.org/10.1002/fld.1896, 2008.
Casulli, V. and Walters, R. A.: An unstructured grid, three-dimensional
model based on the shallow water equations, Int. J.
Numer. Meth. Fl., 32, 331–348, https://doi.org/10.1002/(SICI)1097-0363(20000215)32:3<331::AID-FLD941>3.0.CO;2-C, 2000.
Dijkstra, Y. M., Schuttelaars, H. M., and Burchard, H.: Generation of
exchange flows in estuaries by tidal and gravitational eddy viscosity-shear
covariance (ESCO), J. Geophys. Res.-Oceans, 122, 4217–4237,
https://doi.org/10.1002/2016JC012379, 2017.
DIN 4049-1:1992-12: Hydrologie, Grundbegriffe, https://www.din.de/de/wdc-beuth:din21:1987523 (last access: 2 December 2022), 1992.
Dronkers, J. and van de Kreeke, J.: Experimental determination of salt
intrusion mechanisms in the Volkerak estuary, Neth. J. Sea
Res., 20, 1–19, https://doi.org/10.1016/0077-7579(86)90056-6, 1986.
Dyer, K. R.: The salt balance in stratified estuaries, Estuar. Coast.
Mar. Sci., 2, 273–281, https://doi.org/10.1016/0302-3524(74)90017-6,
1974.
Geyer, W. R. and MacCready, P.: The Estuarine Circulation, Annu. Rev.
Fluid Mech., 46, 175–197, https://doi.org/10.1146/annurev-fluid-010313-141302, 2014.
Grabemann, I., Krause, G., and Siedler, G.: Langzeitige Änderung des
Salzgehaltes in der Unterweser, Deutsche Hydrographische Zeitschrift, 36,
61–77, https://doi.org/10.1007/BF02313285, 1983.
Grasso, F. and Le Hir, P.: Influence of morphological changes on suspended
sediment dynamics in a macrotidal estuary: Diachronic analysis in the Seine
Estuary (France) from 1960 to 2010, Ocean Dynam., 69, 83–100,
https://doi.org/10.1007/s10236-018-1233-x, 2019.
Gundlach, J., Zorndt, A., van Prooijen, B. C., and Wang, Z. B.: Two-Channel
System Dynamics of the Outer Weser Estuary – A Modeling Study, J. Mar. Sci. Eng., 9, 448,
https://doi.org/10.3390/jmse9040448, 2021.
Hagen, R., Plüß, A., Ihde, R., Freund, J., Dreier, N., Nehlsen, E., Schrage, N., Fröhle, P., and Kösters, F.: An integrated marine data collection for the German Bight – Part 2: Tides, salinity, and waves (1996–2015), Earth Syst. Sci. Data, 13, 2573–2594, https://doi.org/10.5194/essd-13-2573-2021, 2021a.
Hagen, R., Plüß, A., Jänicke, L., Freund, J., Jensen, J., and
Kösters, F.: A Combined Modeling and Measurement Approach to Assess the
Nodal Tide Modulation in the North Sea, J. Geophys. Res.-Oceans, 126, 637,
https://doi.org/10.1029/2020JC016364, 2021b.
Hubert, K., Wurpts, A., and Berkenbrink, C.: Interaction of Estuarine
Morphology and adjacent Coastal Water Tidal Dynamics (ALADYN-C), Die
Küste, 89, 193–217, https://doi.org/10.18171/1.089108, 2021.
Hughes, F. W. and Rattray, M.: Salt flux and mixing in the Columbia River Estuary, Estuar. Coast. Mar. Sci., 10, 479–493, https://doi.org/10.1016/S0302-3524(80)80070-3, 1980.
Ianniello, J. P.: Tidally Induced Residual Currents in Estuaries of Variable
Breadth and Depth, J. Phys. Oceanogr., 9, 962–974,
https://doi.org/10.1175/1520-0485(1979)009<0962:TIRCIE>2.0.CO;2, 1979.
Jay, D. A. and Musiak, J. D.: Particle trapping in estuarine tidal flows, J.
Geophys. Res., 99, 20445, https://doi.org/10.1029/94JC00971, 1994.
Jay, D. A., Leffler, K., and Degens, S.: Long-Term Evolution of Columbia
River Tides, J. Waterway, Port, Coastal, Ocean Eng., 137, 182–191,
https://doi.org/10.1061/(ASCE)WW.1943-5460.0000082, 2011.
Kösters, F., Grabemann, I., and Schubert, R.: On SPM Dynamics in the
Turbidity Maximum Zone of the Weser Estuary, Die Küste, 81, 393–408, https://hdl.handle.net/20.500.11970/101702 (last access: 2 December 2022),
2014.
Krause, G.: Grundlagen zur Trendermittlung des Salzgehalts in
Tide-Ästuarien, Deutsche Hydrographische Zeitschrift, 32, 233–247,
https://doi.org/10.1007/BF02226051, 1979.
Lang, G.: Analyse von HN-Modell-Ergebnissen im Tidegebiet, Mitteilungsblatt
der Bundesanstalt für Wasserbau, 86, 101–108, https://wiki.baw.de/de/index.php/Analyse_der_Berechnungsergebnisse (last access: 2 December 2022), 2003.
Lange, D., Müller, H., Piechotta, F., and Schubert, R.: The Weser
Estuary, Die Küste, 74, 275–287, https://hdl.handle.net/20.500.11970/101611 (last access: 2 December 2022), 2008.
Liu, W.-C., Ke, M.-H., and Liu, H.-M.: Response of Salt Transport and
Residence Time to Geomorphologic Changes in an Estuarine System, Water, 12,
1091, https://doi.org/10.3390/w12041091, 2020.
Malcherek, A.: Gezeiten und Wellen: Die Hydromechanik der
Küstengewässer, PRAXIS, edited by: Harms, R. and Koch, S., Vieweg
+Teubner, ISBN 9783834807878, 2010.
Milbradt, P., Valerius, J., and Zeiler, M.: Das Funktionale Bodenmodell:
Aufbereitung einer konsistenten Datenbasis für die Morphologie und
Sedimentologie, Die Küste, 83, 39–63, https://hdl.handle.net/20.500.11970/101736 (last access: 2 December 2022), 2015.
Murphy, A. H.: Skill Scores Based on the Mean Square Error and Their
Relationships to the Correlation Coefficient, Mon. Weather Rev., 116,
2417–2424, https://doi.org/10.1175/1520-0493(1988)116<2417:SSBOTM>2.0.CO;2, 1988.
NLWKN: Deutsches Gewässerkundliches Jahrbuch: Weser- und Emsgebiet 2015,
Hildesheim, https://www.nlwkn.niedersachsen.de/startseite/wasserwirtschaft/publikationen/deutsches_gewasserkundliches_jahrbuch/deutsches-gewaesserkundliches-jahrbuch-weser-und-emsgebiet-43607.html (last access: 2 December 2022), 2018.
Park, J. K. and James, A.: Mass flux estimation and mass transport mechanism
in estuaries, Limnol. Oceanogr., 35, 1301–1313,
https://doi.org/10.4319/lo.1990.35.6.1301, 1990.
Ralston, D. K. and Geyer, W. R.: Response to Channel Deepening of the
Salinity Intrusion, Estuarine Circulation, and Stratification in an
Urbanized Estuary, J. Geophys. Res.-Oceans, 124, 4784–4802,
https://doi.org/10.1029/2019JC015006, 2019.
Ralston, D. K., Geyer, W. R., and Lerczak, J. A.: Structure, variability,
and salt flux in a strongly forced salt wedge estuary, J.
Geophys. Res.-Earth, 115, C06005,
https://doi.org/10.1029/2009JC005806, 2010.
Ralston, D. K., Talke, S., Geyer, W. R., Al-Zubaidi, H. A. M., and
Sommerfield, C. K.: Bigger Tides, Less Flooding: Effects of Dredging on
Barotropic Dynamics in a Highly Modified Estuary, J. Geophys. Res.-Oceans,
124, 196–211, https://doi.org/10.1029/2018JC014313, 2019.
Rasquin, C., Seiffert, R., Wachler, B., and Winkel, N.: The significance of coastal bathymetry representation for modelling the tidal response to mean sea level rise in the German Bight, Ocean Sci., 16, 31–44, https://doi.org/10.5194/os-16-31-2020, 2020.
Simpson, J. H., Brown, J., Matthews, J., and Allen, G.: Tidal Straining,
Density Currents, and Stirring in the Control of Estuarine Stratification,
Estuaries, 13, 125, https://doi.org/10.2307/1351581, 1990.
van Maren, D. S., Winterwerp, J. C., and Vroom, J.: Fine sediment transport
into the hyper-turbid lower Ems River: The role of channel deepening and
sediment-induced drag reduction, Ocean Dynam., 65, 589–605,
https://doi.org/10.1007/s10236-015-0821-2, 2015.
van Rijn, L. C.: Unified View of Sediment Transport by Currents and Waves: I
Initiation of Motion, Bed Roughness, and Bed-Load Transport, J.
Hydraul. Eng., 133, 649–667,
https://doi.org/10.1061/(ASCE)0733-9429(2007)133:6(649), 2007.
Wahl, T., Haigh, I. D., Woodworth, P. L., Albrecht, F., Dillingh, D.,
Jensen, J., Nicholls, R. J., Weisse, R., and Wöppelmann, G.: Observed
mean sea level changes around the North Sea coastline from 1800 to present,
Earth-Sci. Rev., 124, 51–67,
https://doi.org/10.1016/j.earscirev.2013.05.003, 2013.
Wei, X., Williams, M. E., Brown, J. M., Thorne, P. D., and Amoudry, L. O.:
Salt Intrusion as a Function of Estuary Length in Periodically Weakly
Stratified Estuaries, Geophys. Res. Lett., 49,
https://doi.org/10.1029/2022GL099082, 2022.
Wiltshire, K. H., Malzahn, A. M., Wirtz, K., Greve, W., Janisch, S.,
Mangelsdorf, P., Manly, B. F. J., and Boersma, M.: Resilience of North Sea
phytoplankton spring bloom dynamics: An analysis of long-term data at
Helgoland Roads, Limnol. Oceanogr., 53, 1294–1302,
https://doi.org/10.4319/lo.2008.53.4.1294, 2008.
Winterwerp, J. C., Wang, Z. B., Braeckel, A., Holland, G., and Kösters,
F.: Man-induced regime shifts in small estuaries – II: a comparison of
rivers, Ocean Dynam., 63, 1293–1306, https://doi.org/10.1007/s10236-013-0663-8, 2013.
WSV: Water level, salinity, and temperature measurement data of the Weser estuary, Federal Waterways and Shipping Administration [data set], https://www.kuestendaten.de/DE/Services/Messreihen_Dateien_Download/Download_Zeitreihen_node.html, last access: 5 December 2022.
Short summary
River engineering measures greatly changed tidal dynamics in the Weser estuary. We studied the effect on saltwater intrusion with numerical models. Our analysis shows that a deepening of the navigation channel causes saltwater to intrude further into the Weser estuary. This effect is mostly masked by the natural variability of river discharge. In our study, it proved essential to recalibrate individual hindcast models due to differences in sediments, bed forms, and underlying bathymetric data.
River engineering measures greatly changed tidal dynamics in the Weser estuary. We studied the...
