Articles | Volume 21, issue 2
https://doi.org/10.5194/os-21-619-2025
© Author(s) 2025. 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-21-619-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
14 Mar 2025
Research article |
| 14 Mar 2025
| 14 Mar 2025
Alongshore sediment transport analysis for a semi-enclosed basin: a case study of the Gulf of Riga, the Baltic Sea
Department of Cybernetics, School of Science, Tallinn University of Technology, 19086 Tallinn, Estonia
Estonian Academy of Sciences, Kohtu 6, 10130 Tallinn, Estonia
Mikołaj Zbigniew Jankowski
Department of Cybernetics, School of Science, Tallinn University of Technology, 19086 Tallinn, Estonia
Maris Eelsalu
Department of Cybernetics, School of Science, Tallinn University of Technology, 19086 Tallinn, Estonia
Kevin Ellis Parnell
Department of Cybernetics, School of Science, Tallinn University of Technology, 19086 Tallinn, Estonia
Maija Viška
Department of Marine Monitoring, Latvian Institute of Aquatic Ecology, 1007 Riga, Latvia
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Marcus Reckermann, Anders Omstedt, Tarmo Soomere, Juris Aigars, Naveed Akhtar, Magdalena Bełdowska, Jacek Bełdowski, Tom Cronin, Michał Czub, Margit Eero, Kari Petri Hyytiäinen, Jukka-Pekka Jalkanen, Anders Kiessling, Erik Kjellström, Karol Kuliński, Xiaoli Guo Larsén, Michelle McCrackin, H. E. Markus Meier, Sonja Oberbeckmann, Kevin Parnell, Cristian Pons-Seres de Brauwer, Anneli Poska, Jarkko Saarinen, Beata Szymczycha, Emma Undeman, Anders Wörman, and Eduardo Zorita
Earth Syst. Dynam., 13, 1–80, https://doi.org/10.5194/esd-13-1-2022, https://doi.org/10.5194/esd-13-1-2022, 2022
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As part of the Baltic Earth Assessment Reports (BEAR), we present an inventory and discussion of different human-induced factors and processes affecting the environment of the Baltic Sea region and their interrelations. Some are naturally occurring and modified by human activities, others are completely human-induced, and they are all interrelated to different degrees. The findings from this study can largely be transferred to other comparable marginal and coastal seas in the world.
Ralf Weisse, Inga Dailidienė, Birgit Hünicke, Kimmo Kahma, Kristine Madsen, Anders Omstedt, Kevin Parnell, Tilo Schöne, Tarmo Soomere, Wenyan Zhang, and Eduardo Zorita
Earth Syst. Dynam., 12, 871–898, https://doi.org/10.5194/esd-12-871-2021, https://doi.org/10.5194/esd-12-871-2021, 2021
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The study is part of the thematic Baltic Earth Assessment Reports – a series of review papers summarizing the knowledge around major Baltic Earth science topics. It concentrates on sea level dynamics and coastal erosion (its variability and change). Many of the driving processes are relevant in the Baltic Sea. Contributions vary over short distances and across timescales. Progress and research gaps are described in both understanding details in the region and in extending general concepts.
Nadezhda Kudryavtseva, Tarmo Soomere, and Rain Männikus
Nat. Hazards Earth Syst. Sci., 21, 1279–1296, https://doi.org/10.5194/nhess-21-1279-2021, https://doi.org/10.5194/nhess-21-1279-2021, 2021
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We demonstrate a finding of a very sudden change in the nature of water level extremes in the Gulf of Riga which coincides with weakening of correlation with North Atlantic Oscillation. The shape of the distribution is variable with time; it abruptly changed for several years and was suddenly restored. If similar sudden changes happen in other places in the world, not taking into account the non-stationarity can lead to significant underestimation of future risks from extreme-water-level events.
Tarmo Soomere, Katri Pindsoo, Nadezhda Kudryavtseva, and Maris Eelsalu
Ocean Sci., 16, 1047–1065, https://doi.org/10.5194/os-16-1047-2020, https://doi.org/10.5194/os-16-1047-2020, 2020
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Extreme water levels are often created by several drivers with different properties. For example, the contribution from the water volume of the Baltic Sea follows a Gaussian distribution, but storm surges represent a Poisson process. We show that wave set-up heights (the third major component of high water levels) usually follow an exponential distribution and thus also represent a Poisson process. However, at some locations set-up heights better match an inverse Gaussian (Wald) distribution.
Oxana Kurkina, Tatyana Talipova, Tarmo Soomere, Ayrat Giniyatullin, and Andrey Kurkin
Nonlin. Processes Geophys., 24, 645–660, https://doi.org/10.5194/npg-24-645-2017, https://doi.org/10.5194/npg-24-645-2017, 2017
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Large internal waves may be a great danger to offshore structures. The breaking of such waves may strongly modify the seabed. Their core properties depend on how temperature and salinity vary in the water column. These variations are represented by three vertical locations and four coefficients of the relevant equation. We established how these seven quantities vary in the South China Sea for waves of the second mode (which create compressions or expansions of the intermediate water layer).
Nadezhda Kudryavtseva and Tarmo Soomere
Earth Syst. Dynam., 8, 697–706, https://doi.org/10.5194/esd-8-697-2017, https://doi.org/10.5194/esd-8-697-2017, 2017
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We discuss for the first time changes in the wave climate in the Baltic Sea over the last 2 decades derived from satellite altimetry data spanning over 26 years. We found in the study that there are variations in the wave climate of the Baltic Sea, which can be interpreted as being caused predominantly by a rotation of wind direction rather than increased wind speed, implying that associated variations in the airflow direction can be a dominant driver of regional climate changes.
Tarmo Soomere and Katri Pindsoo
Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2016-76, https://doi.org/10.5194/esd-2016-76, 2017
Revised manuscript not accepted
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Wave-induced set-up is a nonlinear phenomenon that results in a rise in the mean water level at the waterline and may contribute to the formation of coastal flooding. We study the shape of probability distribution of the wave set-up heights near Tallinn in the Baltic Sea. Resulted distribution deviates from the ones that usually reflect the wave heights, this signals that extreme set-up events are more probable that it could be expected from the probability of occurrence of severe seas.
O. E. Kurkina, A. A. Kurkin, E. A. Rouvinskaya, and T. Soomere
Nonlin. Processes Geophys., 22, 117–132, https://doi.org/10.5194/npg-22-117-2015, https://doi.org/10.5194/npg-22-117-2015, 2015
Short summary
Short summary
We have derived exact analytical expressions for the coefficients of evolution equations of long wave motion in the three-layer fluid with arbitrary parameters of the layers and established interrelations of these equations for different interfaces. To our understanding, the core advancement is the clarification and mapping of the regimes of soliton appearance and propagation in this environment that is much more realistic for the description of ocean internal waves.
T. Soomere, K. Pindsoo, S. R. Bishop, A. Käärd, and A. Valdmann
Nat. Hazards Earth Syst. Sci., 13, 3049–3061, https://doi.org/10.5194/nhess-13-3049-2013, https://doi.org/10.5194/nhess-13-3049-2013, 2013
Marcus Reckermann, Anders Omstedt, Tarmo Soomere, Juris Aigars, Naveed Akhtar, Magdalena Bełdowska, Jacek Bełdowski, Tom Cronin, Michał Czub, Margit Eero, Kari Petri Hyytiäinen, Jukka-Pekka Jalkanen, Anders Kiessling, Erik Kjellström, Karol Kuliński, Xiaoli Guo Larsén, Michelle McCrackin, H. E. Markus Meier, Sonja Oberbeckmann, Kevin Parnell, Cristian Pons-Seres de Brauwer, Anneli Poska, Jarkko Saarinen, Beata Szymczycha, Emma Undeman, Anders Wörman, and Eduardo Zorita
Earth Syst. Dynam., 13, 1–80, https://doi.org/10.5194/esd-13-1-2022, https://doi.org/10.5194/esd-13-1-2022, 2022
Short summary
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As part of the Baltic Earth Assessment Reports (BEAR), we present an inventory and discussion of different human-induced factors and processes affecting the environment of the Baltic Sea region and their interrelations. Some are naturally occurring and modified by human activities, others are completely human-induced, and they are all interrelated to different degrees. The findings from this study can largely be transferred to other comparable marginal and coastal seas in the world.
Ralf Weisse, Inga Dailidienė, Birgit Hünicke, Kimmo Kahma, Kristine Madsen, Anders Omstedt, Kevin Parnell, Tilo Schöne, Tarmo Soomere, Wenyan Zhang, and Eduardo Zorita
Earth Syst. Dynam., 12, 871–898, https://doi.org/10.5194/esd-12-871-2021, https://doi.org/10.5194/esd-12-871-2021, 2021
Short summary
Short summary
The study is part of the thematic Baltic Earth Assessment Reports – a series of review papers summarizing the knowledge around major Baltic Earth science topics. It concentrates on sea level dynamics and coastal erosion (its variability and change). Many of the driving processes are relevant in the Baltic Sea. Contributions vary over short distances and across timescales. Progress and research gaps are described in both understanding details in the region and in extending general concepts.
Nadezhda Kudryavtseva, Tarmo Soomere, and Rain Männikus
Nat. Hazards Earth Syst. Sci., 21, 1279–1296, https://doi.org/10.5194/nhess-21-1279-2021, https://doi.org/10.5194/nhess-21-1279-2021, 2021
Short summary
Short summary
We demonstrate a finding of a very sudden change in the nature of water level extremes in the Gulf of Riga which coincides with weakening of correlation with North Atlantic Oscillation. The shape of the distribution is variable with time; it abruptly changed for several years and was suddenly restored. If similar sudden changes happen in other places in the world, not taking into account the non-stationarity can lead to significant underestimation of future risks from extreme-water-level events.
Tarmo Soomere, Katri Pindsoo, Nadezhda Kudryavtseva, and Maris Eelsalu
Ocean Sci., 16, 1047–1065, https://doi.org/10.5194/os-16-1047-2020, https://doi.org/10.5194/os-16-1047-2020, 2020
Short summary
Short summary
Extreme water levels are often created by several drivers with different properties. For example, the contribution from the water volume of the Baltic Sea follows a Gaussian distribution, but storm surges represent a Poisson process. We show that wave set-up heights (the third major component of high water levels) usually follow an exponential distribution and thus also represent a Poisson process. However, at some locations set-up heights better match an inverse Gaussian (Wald) distribution.
Oxana Kurkina, Tatyana Talipova, Tarmo Soomere, Ayrat Giniyatullin, and Andrey Kurkin
Nonlin. Processes Geophys., 24, 645–660, https://doi.org/10.5194/npg-24-645-2017, https://doi.org/10.5194/npg-24-645-2017, 2017
Short summary
Short summary
Large internal waves may be a great danger to offshore structures. The breaking of such waves may strongly modify the seabed. Their core properties depend on how temperature and salinity vary in the water column. These variations are represented by three vertical locations and four coefficients of the relevant equation. We established how these seven quantities vary in the South China Sea for waves of the second mode (which create compressions or expansions of the intermediate water layer).
Nadezhda Kudryavtseva and Tarmo Soomere
Earth Syst. Dynam., 8, 697–706, https://doi.org/10.5194/esd-8-697-2017, https://doi.org/10.5194/esd-8-697-2017, 2017
Short summary
Short summary
We discuss for the first time changes in the wave climate in the Baltic Sea over the last 2 decades derived from satellite altimetry data spanning over 26 years. We found in the study that there are variations in the wave climate of the Baltic Sea, which can be interpreted as being caused predominantly by a rotation of wind direction rather than increased wind speed, implying that associated variations in the airflow direction can be a dominant driver of regional climate changes.
Tarmo Soomere and Katri Pindsoo
Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2016-76, https://doi.org/10.5194/esd-2016-76, 2017
Revised manuscript not accepted
Short summary
Short summary
Wave-induced set-up is a nonlinear phenomenon that results in a rise in the mean water level at the waterline and may contribute to the formation of coastal flooding. We study the shape of probability distribution of the wave set-up heights near Tallinn in the Baltic Sea. Resulted distribution deviates from the ones that usually reflect the wave heights, this signals that extreme set-up events are more probable that it could be expected from the probability of occurrence of severe seas.
O. E. Kurkina, A. A. Kurkin, E. A. Rouvinskaya, and T. Soomere
Nonlin. Processes Geophys., 22, 117–132, https://doi.org/10.5194/npg-22-117-2015, https://doi.org/10.5194/npg-22-117-2015, 2015
Short summary
Short summary
We have derived exact analytical expressions for the coefficients of evolution equations of long wave motion in the three-layer fluid with arbitrary parameters of the layers and established interrelations of these equations for different interfaces. To our understanding, the core advancement is the clarification and mapping of the regimes of soliton appearance and propagation in this environment that is much more realistic for the description of ocean internal waves.
T. Soomere, K. Pindsoo, S. R. Bishop, A. Käärd, and A. Valdmann
Nat. Hazards Earth Syst. Sci., 13, 3049–3061, https://doi.org/10.5194/nhess-13-3049-2013, https://doi.org/10.5194/nhess-13-3049-2013, 2013
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Zhongyuan Lin, Guang Zhang, Huazhi Zou, and Wenping Gong
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Elina Miettunen, Laura Tuomi, Antti Westerlund, Hedi Kanarik, and Kai Myrberg
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Julio Salcedo-Castro, Antonio Olita, Freddy Saavedra, Gonzalo S. Saldías, Raúl C. Cruz-Gómez, and Cristian D. De la Torre Martínez
Ocean Sci., 19, 1687–1703, https://doi.org/10.5194/os-19-1687-2023, https://doi.org/10.5194/os-19-1687-2023, 2023
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Considering the relevance and impact of river discharges on the coastal environment, it is necessary to understand the processes associated with river plume dynamics in different regions and at different scales. Modeling studies focused on the eastern Pacific coast under the influence of the Humboldt Current are scarce. Here, we conduct for the first time an interannual modeling study of two river plumes off central Chile and discuss their characteristics.
Qiyan Ji, Lei Han, Lifang Jiang, Yuting Zhang, Minghong Xie, and Yu Liu
Ocean Sci., 19, 1561–1578, https://doi.org/10.5194/os-19-1561-2023, https://doi.org/10.5194/os-19-1561-2023, 2023
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Accurate wave forecasts are essential to marine engineering safety. The research designs a model with combined signal decomposition and multiple neural network algorithms to predict wave parameters. The hybrid wave prediction model has good robustness and generalization ability. The contribution of the various algorithms to the model prediction skill was analyzed by the ablation experiments. This work provides a neoteric view of marine element forecasting based on artificial intelligence.
Cited articles
Aagaard, T., Brinkkemper, J., Christensen, D. F., Hughes, M. G., and Ruessink, G.: Surf zone turbulence and suspended sediment dynamics – A review, J. Mar. Sci. Eng., 9, 1300, https://doi.org/10.3390/jmse9111300, 2021.
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Eelsalu, M., Parnell, K. E., and Soomere, T.: Sandy beach evolution in the low-energy microtidal Baltic Sea: attribution of changes to hydrometeorological forcing, Geomorphology, 414, 108383, https://doi.org/10.1016/j.geomorph.2022.108383, 2022.
Eelsalu, M., Viigand, K., and Soomere, T.: Quantification of sediment budget in extensively developed urban areas: a case study of Tallinn Bay, the Baltic Sea, Regional Studies in Marine Science, 67, 103199, https://doi.org/10.1016/j.rsma.2023.103199, 2023.
Eelsalu, M., Soomere, T., and Jankowski, M. Z.: Climate change driven alongshore variations of directional forcing of sediment transport on the eastern Baltic Sea coast, J. Coastal Res., 113, 256–260, https://doi.org/10.2112/JCR-SI113-051.1, 2024a.
Eelsalu, M., Viigand, K., Soomere, T., and Parnell, K. E.: Systematic analysis of alongshore sediment transport patterns in varying sea level conditions for evaluating stability of the coastal areas in the microtidal Baltic Sea, J. Coastal Res., 113, 53–57, https://doi.org/10.2112/JCR-SI113-011.1, 2024b.
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Eelsalu, M., Soomere, T., Parnell, K. E., and Viška, M.: Attribution of alterations in coastal processes in the southern and eastern Baltic Sea to climate change driven modifications of coastal drivers, Oceanologia, 67, 67103, https://doi.org/10.5697/LXTZ5389, 2025b.
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Giudici, A., Jankowski, M. Z., Männikus, R., Najafzadeh, F., Suursaar, Ü., and Soomere, T.: A comparison of Baltic Sea wave properties simulated using two modelled wind data sets, Estuar. Coast. Shelf S., 290, 108401, https://doi.org/10.1016/j.ecss.2023.108401, 2023.
Harff, J., Deng, J. J., Dudzinska-Nowak, J., Fröhle, P., Groh, A., Hünicke, B., Soomere, T., and Zhang, W. Y.: What determines the change of coastlines in the Baltic Sea?, in: Coastline Changes of the Baltic Sea from South to East: Past and Future Projection, Coastal Research Library, vol. 19, edited by: Harff, J., Furmańczyk, K., and von Storch, H., Springer, 15–35, https://doi.org/10.1007/978-3-319-49894-2_2, 2017.
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Hünicke, B., Zorita, E., Soomere, T., Madsen, K. S., Johansson, M., and Suursaar, Ü.: Recent change – Sea level and wind waves, in: Second Assessment of Climate Change for the Baltic Sea Basin, Regional Climate Studies, edited by: The BACC II Author Team, Springer, 155–185, https://doi.org/10.1007/978-3-319-16006-1_9, 2015.
Jankowski, M. Z., Soomere, T., Parnell, K. E., and Eelsalu, M.: Alongshore sediment transport in the eastern Baltic Sea, J. Coastal Res., 113, 261–265, https://doi.org/10.2112/JCR-SI113-052.1, 2024.
Karpin, V., Heinsalu, A., Ojala, A. E. K., and Virtasalo, J.: Offshore murtoos indicate warm-based Fennoscandian ice-sheet conditions during the Bølling warming in the northern Gulf of Riga, Baltic Sea, Geomorphology, 430, 108655, https://doi.org/10.1016/j.geomorph.2023.108655, 2023.
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Männikus, R. and Soomere, T.: Directional variation of return periods of water level extremes in Moonsund and in the Gulf of Riga. Baltic Sea, Reg. Stud. Mar. Sci., 57, 102741, https://doi.org/10.1016/j.rsma.2022.102741, 2023.
Männikus, R., Soomere, T., and Kudryavtseva, N.: Identification of mechanisms that drive water level extremes from in situ measurements in the Gulf of Riga during 1961–2017, Cont. Shelf Res., 182, 22–36, https://doi.org/10.1016/j.csr.2019.05.014, 2019.
Männikus, R., Soomere, T., and Suursaar, Ü.: How do simple wave models perform compared with sophisticated models and measurements in the Gulf of Finland?, Est. J. Earth Sci., 73, 98–111, https://doi.org/10.3176/earth.2024.10, 2024.
Najafzadeh, F. and Soomere, T.: Impact of changes in sea ice cover on wave climate of semi-enclosed seasonally ice-covered water bodies on temperate latitudes: a case study in the Gulf of Riga, Est. J. Earth Sci., 73, 26–36, https://doi.org/10.3176/earth.2024.03, 2024.
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Short summary
Seemingly interconnected beaches are often separated by human-made obstacles and natural divergence areas of sediment flux. We decompose the sedimentary shores of the Gulf of Riga into five naturally almost isolated compartments based on the analysis of wave-driven sediment flux. The western, southern, and eastern shores have quite different and fragmented sediment transport regimes. The transport rates along different shore segments show extensive interannual variations but no explicit trends.
Seemingly interconnected beaches are often separated by human-made obstacles and natural...
