Advertisement

Investigations of Sea Ice Dynamics in the Baltic Sea

  • Matti Leppäranta
Part of the Solid Mechanics and Its Applications book series (SMIA, volume 94)

Abstract

The Baltic Sea is a semi-enclosed basin in the seasonal sea ice zone. This ice dynamics problem offers its own particular regime of spatial scales below the large polar seas: the horizontal size of the basins is 100–300 km, the thickness of undeformed ice is up to 1 m, and ice ridges are typically 5–15 m thick. A series of experiments has been performed including drifting stations and coastal bases. The motion of the ice ranges between zero and the free drift state depending on the forcing and ice thickness. Compact, thick ice fields may remain stationary or when drifting the geometry of the fast ice boundary has a strong aligning influence on the ice motion. The compressive strength of such drift ice is 10 to 100 kPa and the shear strength is significant. Mathematical models have been developed for the ice dynamics in the Baltic Sea; the grid size has been 5 to 20 km, an order of magnitude larger than a typical floe size. The time scales of interest have been short term in ice forecasting and seasonal and interannual in the research of regional climate questions. The linear dimensions of the Baltic ice morphology scale with the Central Arctic by about 1:5 but the models work well with essentially the same parameterization schemes and parameter ranges.

Keywords

Drag Coefficient Synthetic Aperture Radar Geostrophic Wind Free Drift Coastal Basis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Askne, J., Leppäranta, M. and Thompson, T., 1992. Bothnian Experiment in Preparation for ERS-1, 1988 (BEPERS-88) — An Overview. International Journal of Remote Sensing 13: 2377–2398.ADSCrossRefGoogle Scholar
  2. Brown, R.A., 1980. Boundary-layer modeling for A1DJEX. In Sea Ice Processes and Models, pp. 387–401. Ed. R.S. Pritchard. University of Washington Press, Seattle.Google Scholar
  3. Dammert, P.G., Leppäranta, M. and Askne, J., 1998. SAR interferometry over Baltic sea ice. International Journal of Remote Sensing 19: 3017–3037.CrossRefGoogle Scholar
  4. Doronin, Yu.P., 1970. On a method of calculating the compactness and drift of ice floes. Tr. Arkt. Antarkt. Inst., 291, 5–17. [English transl. 1970, AIDJEX Bull., 3, 22–39]Google Scholar
  5. Haapala, J., 2000. Modelling of the seasonal ice cover of the Baltic Sea. Report Series in Geophysics No. 42. Department of Geophysics, University of Helsinki.Google Scholar
  6. Haapala, J. and Leppäranta, M., 1996. Simulations of the Baltic Sea ice season with a coupled ice-ocean model. Tellus 48A: 622–643.CrossRefGoogle Scholar
  7. Haapala, J. and Leppäranta, M., 1997. ZIP-97 data report. Report Series of Geophysics 37, pp. 3–25. Department of Geophysics, University of Helsinki.Google Scholar
  8. Hibler III, W.D., 1979. A dynamic-thermodynamic sea ice model. J. Phys. Oceanogr., 9: 815–846.ADSCrossRefGoogle Scholar
  9. Hibler III, W. D., 1986. Ice Dynamics. In Geophysics of Sea Ice, pp. 577–640. Ed. N. Untersteiner. Plenum Press.Google Scholar
  10. Kankaanpää, P., 1997. Distribution, morphology and structure of sea ice pressure ridges in the Baltic Sea. Fennia 175: 139–240.Google Scholar
  11. Leppäranta, M., 1981a. An ice drift model for the Baltic Sea. Tellus 33: 583–596.ADSCrossRefGoogle Scholar
  12. Leppäranta, M., 1981b. On the structure and mechanics of pack ice in the Bothnian Bay. Finnish Marine Research 248: 3–86.Google Scholar
  13. Leppäranta, M., 1998. The dynamics of sea ice. In Physics of Ice-Covered Seas, Vol. 1, pp. 305–342. Ed. M. Leppäranta. Helsinki University Press.Google Scholar
  14. Leppäranta, M. and Hakala, R., 1992. Structure and strength of first-year sea ice ridges in the Baltic Sea. Cold Regions Research and Technology 20: 295–311.CrossRefGoogle Scholar
  15. Leppäranta, M. and Omstedt, A., 1990. Dynamic coupling of sea ice and water for an ice field with free boundaries. Tellus 42A: 482–495.CrossRefGoogle Scholar
  16. Leppäranta, M. and Zhang, Z., 1992. A viscous-plastic ice dynamics test model for the Baltic Sea. Finnish Institute of Marine Research Internal Report 1992(3), 14 p.Google Scholar
  17. Leppäranta, M., Zhang, Z., Haapala, J. and Stipa, T., 2001. Sea ice kinematics measured with GPS drifters. Annals of Glaciology 33, in press.Google Scholar
  18. Lewis, J.E., Leppäranta, M. and Granberg, H.B., 1993. Statistical features of the sea ice surface topography in the Baltic Sea. Tellus 45A: 127–142.Google Scholar
  19. McPhee, M.G., 1980. An analysis of pack ice drift in summer. In Sea Ice Processes and Models, pp. 62–75. Ed. R.S. Pritchard. University of Washington, Seattle.Google Scholar
  20. McPhee, M.G., 1982. Sea ice drag laws and simple boundary layer concepts, including application to rapid melting. Rep. 82–4. U.S. Army Cold Regions Research and Engineering Laboratory, Hanover, N.H.Google Scholar
  21. Palosuo, E., 1975. Formation and structure of the ice ridges in the Baltic, Winter Navigation Research Board. Res. Rep. No. 12. Finnish Board of Navigation, Helsinki.Google Scholar
  22. Sun, Y., 1996. Automatic ice motion retrieval from ERS-1 SAR images using the optical flow method. International Journal of Remote Sensing 17: 2059–2087.ADSCrossRefGoogle Scholar
  23. Thorndike, A.S. and Colony, R., 1982. Sea ice response to geostrophic winds. J. Geophys. Res. 87: 5845–5852.ADSCrossRefGoogle Scholar
  24. Thorndike, A.S., Rothrock, D.A.. Maykut G.A. and Colony, R., 1975. The thickness distribution of sea ice. J. Geophys. Res. 80: 4501–4513.ADSCrossRefGoogle Scholar
  25. Zhang, Z., 2000. Comparisons between observed and simulated ice motion in the Northern Baltic Sea. Geophysica 36: 111–126.Google Scholar
  26. Zhang, Z. and Leppäranta, M., 1995. Modeling the influence of ice on sea level variations in the Baltic Sea. Geophysica 31: 31–46.zbMATHGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2001

Authors and Affiliations

  • Matti Leppäranta
    • 1
  1. 1.Department of GeophysicsUniversity of HelsinkiHelsinkiFinland

Personalised recommendations