In the formerly frozen regions, today's sea level change essentially reflects the post-glacial uplift movement, i.e. the deformation of the earth's surface, resulting in a lowering of local sea level. In the surrounding areas, such as the Netherlands, on the other hand, the sea level rises.
Ice sheets store large quantities of fresh water. Any change in the mass balance of an ice sheet therefore leads to a change in global sea level. During the last glacial maximum, when large ice sheets covered the North American continent and Scandinavia, the globally averaged sea level was almost 120 m below its current level. But even during this time, the resulting changes in ocean load and rotational fluctuations led to temporally and spatially changes in sea level. Reconstructions of the sea level with the help of geological samples, so-called sea level indicators, are an important source of information to quantify the ice mass changes during the glacial cycle as well as to estimate the viscosity distribution in the Earth's interior.
These sea level changes also have an impact on other global processes. During the last glaciation period, large areas of the continental shelves dried up and the ocean tides changed significantly due to the altered current conditions. The latter led, for example, to so-called mega-tide levels in the polar regions.
References:
Sulzbach, R., M. Bagge, M. Schindelegger, and V. Klemann, 2025: The amplified glacial Arctic tide regime—sensitivities and feedback on the Atlantic Ocean. Journal Physical Oceanography, 55, 435–449, doi:10.1175/JPO-D-24-0122.1.
Blanchet, C. L., Ramisch, A., Tjallingii, R., Ionita, M., Laruelle, L., Bagge, M., Klemann, V., Brauer, A. (2024): Climatic pacing of extreme Nile floods during the North African Humid Period. - Nature Geoscience, 17, 638-644. doi:10.1038/s41561-024-01471-9
Sulzbach, R., Klemann, V., Knorr, G., Dobslaw, H., Dümpelmann, H., Lohmann, G., Thomas, M. (2023): Evolution of global ocean tide levels since the Last Glacial Maximum. - Paleoceanography and Paleoclimatology, 38, e2022PA004556. doi:10.1029/2022PA004556
Schachtschneider, R., Saynisch-Wagner, J., Klemann, V., Bagge, M., Thomas, M. (2022): An approach for constraining mantle viscosities through assimilation of palaeo sea level data into a glacial isostatic adjustment model. - Nonlinear Processes in Geophysics, 29, 53-75. doi:10.5194/npg-29-53-2022
Bagge, M., Klemann, V., Steinberger, B., Latinovic, M., Thomas, M. (2021): Glacial-isostatic adjustment models using geodynamically constrained 3D Earth structures. - Geochemistry Geophysics Geosystems (G3), 22, e2021GC009853. doi:10.1029/2021GC009853
Rosentau, A., Klemann, V., Bennike, O., Steffen, H., Wehr, J., Latinovic, M., Bagge, M., Ojala, A., Berglund, M., Becher, G. P., Schoning, K., Hansson, A., Nielsen, L., Clemmensen, L. B., Hede, M. U., Kroon, A., Pejrup, M., Sander, L., Stattegger, K., Schwarzer, K., Lampe, R., Lampe, M., Uścinowicz, S., Bitinas, A., Grudzinska, I., Vassiljev, J., Nirgi, T., Kublitskiy, Y., Subetto, D. (2021): A Holocene relative sea-level database for the Baltic Sea. - Quaternary Science Reviews, 266, 107071. doi:10.1016/j.quascirev.2021.107071
Dobslaw, H., Dill, R., Bagge, M., Klemann, V., Boergens, E., Thomas, M., Dahle, C., Flechtner, F. (2020): Gravitationally consistent mean barystatic sea‐level rise from leakage‐corrected monthly GRACE data. - Journal of Geophysical Research: Solid Earth, 125, e2020JB020923. doi:10.1029/2020JB020923
Palmer, M. D., Gregory, J. M., Bagge, M., Calvert, D., Hagedoorn, J. M., Howard, T., Klemann, V., Lowe, J. A., Roberts, C. D., Slangen, A. B. A., Spada, G. (2020): Exploring the drivers of global and local sea‐level change over the 21st century and beyond. - Earth's Future, 8, e2019EF001413. doi:10.1029/2019EF001413
Latinovic, M., Klemann, V., Irrgang, C., Bagge, M., von Specht, S., Thomas, M. (2018): A statistical method to validate reconstructions of late-glacial relative sea level – Application to shallow water shells rated as low-grade sea-level indicators. - Climate of the Past Discussions. doi:10.5194/cp-2018-50
Martinec, Z., Klemann, V., van der Wal, W., Riva, R. E. M., Spada, G., Sun, Y., Melini, D., Kachuck, S. B., Barletta, V., Simon, K., James, T. S., G A (2018): A benchmark study of numerical implementations of the sea level equation in GIA modelling. - Geophysical Journal International, 215, 389-414. doi:10.1093/gji/ggy280
Düsterhus, A., Rovere, A., Carlson, A. E., Barlow, N. L. M., Bradwell, T., Dutton, A., Gehrels, R., Hibbert, F. D., Hijma, M. P., Horton, B. P., Klemann, V., Kopp, R. E., Sivan, D., Tarasov, L., Törnqvist, T. E. (2016): Palaeo-sea-level and palaeo-ice-sheet databases: problems, strategies, and perspectives. - Climate of the Past, 12, 911-921. doi:10.5194/cp-12-911-2016
Klemann, V., Heim, B., Bauch, H. A., Wetterich, S., Opel, T. (2015): Sea-level evolution of the Laptev Sea and the East Siberian Sea since the last glacial maximum. - arktos, 1, 1, p. 1-8. doi:10.1007/s41063-015-0004-x
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