Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-28T15:20:24.922Z Has data issue: false hasContentIssue false

Salinity evolution and mechanical properties of snow-loaded multiyear sea ice near an ice shelf

Published online by Cambridge University Press:  19 April 2013

A.J. Gough*
Affiliation:
Department of Physics, University of Otago, PO Box 56, Dunedin 9054, New Zealand
A.R. Mahoney
Affiliation:
Department of Physics, University of Otago, PO Box 56, Dunedin 9054, New Zealand Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
P.J. Langhorne
Affiliation:
Department of Physics, University of Otago, PO Box 56, Dunedin 9054, New Zealand
T.G. Haskell
Affiliation:
Industrial Research Ltd, Lower Hutt, New Zealand

Abstract

Sea ice often forms attached to floating ice shelves. Accumulating snow can depress its freeboard, creating a flooded slush layer that may subsequently freeze to form snow ice, rejecting brine as it freezes. The resulting salinity profile determines the mechanical properties of the sea ice. We provide measurements of snow-loaded, multiyear sea ice from summer to winter. Brine from a slush layer is not completely expelled from the sea ice when the slush refreezes to form snow ice. Measurements of sea ice salinity and temperature indicate that the fate of this brine depends on the permeability of the sea ice below it. The sea ice in this study was also deformed by a nearby ice shelf over eleven years at a strain rate $$--><$> \dot{{\epsilon}} $$$ = (-8 ± 3) × 10-4 yr-1 (or 3 × 10-11 s-1). From transects of sea ice thickness and structure we estimate an effective Young's modulus at medium scales for sea ice mostly composed of snow ice of 0.1 GPa < E < 0.4 GPa, suggesting that this eleven year old sea ice cover has similar mechanical properties to warm first year sea ice. This is important for the parameterisations needed to simulate multiyear sea ice in the complex region near an ice shelf.

Type
Physical Sciences
Copyright
Copyright © Antarctic Science Ltd 2013 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Amundson, J.M., Fahnestock, M., Truffer, M., Brown, J., Lthi, M.P. Motyka, R.J. 2010. Ice mélange dynamics and implications for terminus stability, Jakobshavn Isbrae, Greenland. Journal of Geophysical Research, 10.1029/2009JF001405.Google Scholar
Andreas, E.L. Ackley, S.F. 1981. On the differences in ablation seasons of Arctic and Antarctic sea ice. Journal of Atmospheric Science, 39, 440447.Google Scholar
Assur, A. 1958. Composition of sea ice and its tensile strength. In Arctic sea ice. Proceedings of the conference held at Easton, Maryland, 24–27 February 1958. Washington, DC: US National Academy of Sciences, National Research Council, Publication No. 598, 106–138.Google Scholar
Braun, M., Humbert, A. Moll, A. 2009. Changes of Wilkins Ice Shelf over the past 15 years and inferences on its stability. The Cryosphere, 3, 4156.Google Scholar
Brunt, K., Sergienko, O. MacAyeal, D. 2006. Observations of unusual fast-ice conditions in the southwest Ross Sea, Antarctica: preliminary analysis of iceberg and storminess effects. Annals of Glaciology, 44, 183187.Google Scholar
Connolley, W.M. Cattle, H. 1994. The Antarctic climate of the UKMO Unified Model. Antarctic Science, 6, 115122.CrossRefGoogle Scholar
Cox, G.F.N. Weeks, W.F. 1974. Salinity variations in sea ice. Journal of Glaciology, 13, 109120.Google Scholar
Cox, G.F.N. Weeks, W.F. 1983. Equations for determining the gas and brine volumes in sea ice samples. Journal of Glaciology, 29, 306316.CrossRefGoogle Scholar
Cuffey, K. Paterson, W.S.B. 2010. The physics of glaciers, 4th ed. Burlington, MA: Butterwort-Heinemann, 704 pp.Google Scholar
Edgeworth David, T.W. 1914. Antarctica and some of its problems. The Geographical Journal, 43, 605627.CrossRefGoogle Scholar
Eicken, H., Krouse, H.R., Kadko, D. Perovich, D.K. 2002. Tracer studies of pathways and rates of meltwater transport through Arctic summer sea ice. Journal of Geophysical Research, 10.1029/2000JC000583.Google Scholar
Eicken, H., Lensu, M., Leppranta, M., Tucker, W.B.I., Gow, A.J. Salmela, O. 1995. Thickness, structure, and properties of level summer multiyear ice in the Eurasian sector of the Arctic Ocean. Journal of Geophysical Research, 100, 22 69722 710.Google Scholar
Fetterer, F. Untersteiner, N. 1998. Observations of melt ponds on Arctic sea ice. Journal of Geophysical Research, 103, 24 82124 835.CrossRefGoogle Scholar
Fraser, A.D., Massom, R.A., Michael, K.J., Galton-Fenzi, B.K. Lieser, J.L. 2011. East Antarctic landfast sea ice distribution and variability, 2000–2008. Journal of Climate, 25, 11371156.CrossRefGoogle Scholar
Golden, K.M., Ackley, S.F. Lytle, V.I. 1998. The percolation phase transition in sea ice. Science, 282, 22382241.CrossRefGoogle ScholarPubMed
Gough, A.J., Mahoney, A.R., Langhorne, P.J., Williams, M.J.M. Haskell, T.G. In press. Multiyear sea ice near an ice shelf: mechanical properties and brine migration in snow ice. In Proceedings of the 21st IAHR International Symposium on Ice, Dalian, China, 11–15 June 2012. Dalian: Dalian University of Technology Press.Google Scholar
Gough, A.J., Mahoney, A.R., Langhorne, P.J., Williams, M.J.M., Robinson, N.J. Haskell, T.G. 2012. Signatures of supercooling: McMurdo Sound platelet ice. Journal of Glaciology, 58, 3850.Google Scholar
Gow, A.J. Williamson, T. 1976. Rheological implications of the internal structure and crystal fabrics of the West Antarctic ice sheet as revealed by deep core drilling at Byrd Station. Geological Society of America Bulletin, 87, 16651677.Google Scholar
Gow, A.J., Ackley, S., Weeks, W. Govoni, J. 1982. Physical and structural characteristics of Antarctic sea ice. Annals of Glaciology, 3, 113117.Google Scholar
Haas, C., Thomas, D. Bareiss, J. 2001. Surface properties and processes of perennial Antarctic sea ice in summer. Journal of Glaciology, 47, 613625.Google Scholar
Heine, A. 1963. Ice breakout around the southern end of Ross Island, Antarctica. New Zealand Journal of Geology and Geophysics, 6, 395401.CrossRefGoogle Scholar
Hudier, E.-J., Ingram, R. Shirasawa, K. 1995. Upward flushing of seawater through first year ice. Atmosphere-Ocean, 33, 569580.Google Scholar
Humbert, A. Steinhage, D. 2011. The evolution of the western rift area of the Fimbul Ice Shelf, Antarctica. The Cryosphere, 5, 931944.Google Scholar
Humbert, A., Kleiner, T., Mohrholz, C.-O., Oelke, C., Greve, R. Lange, M.A. 2009. A comparative modeling study of the Brunt Ice Shelf/Stancomb-Wills Ice Tongue system, East Antarctica. Journal of Glaciology, 55, 5365.Google Scholar
Jeffries, M.O. Adolphs, U. 1997. Early winter ice and snow thickness distribution, ice structure and development of the western Ross Sea pack ice between the ice-edge and the Ross Ice Shelf. Antarctic Science, 9, 188200.Google Scholar
Johnson, J.B. Metzner, R.C. 1990. Thermal expansion coefficients for sea ice. Journal of Glaciology, 36, 343349.CrossRefGoogle Scholar
Lange, M.A. 1988. Basic properties of Antarctic sea ice as revealed by textural analysis of ice cores. Annals of Glaciology, 10, 95101.CrossRefGoogle Scholar
Langway, C.C. 1958. Ice fabrics and the universal stage. CRREL Technical Report, No. 62, 16 pp.Google Scholar
Leonard, G.H., Purdie, C.R., Langhorne, P.J., Haskell, T.G., Williams, M.J.M. Frew, R.D. 2006. Observations of platelet ice growth and oceanographic conditions during the winter of 2003 in McMurdo Sound, Antarctica. Journal of Geophysical Research, 10.1029/2005JC002952.Google Scholar
Lytle, V.I. Ackley, S.F. 1996. Heat flux through sea ice in the western Weddell Sea: convective and conductive transfer processes. Journal of Geophysical Research, 101, 88538868.CrossRefGoogle Scholar
Mahoney, A., Eicken, H., Shapiro, L. Grenfell, T.C. 2004. Ice motion and driving forces during a spring ice shove on the Alaskan Chukchi coast. Journal of Glaciology, 50, 195207.Google Scholar
Mahoney, A., Gearheard, S., Oshima, T. Qillaq, T. 2009. Sea ice thickness measurements from a community based observing network. Bulletin of the American Meteorological Society, 90, 370377.Google Scholar
Mahoney, A.R., Gough, A.J., Langhorne, P.J., Robinson, N.J., Stevens, C.L., Williams, M.M.J. Haskell, T.G. 2011. The seasonal appearance of ice shelf water in coastal Antarctica and its effect on sea ice growth. Journal of Geophysical Research, 10.1029/2011JC007060.Google Scholar
Maksym, T. Jeffries, M.O. 2000. A one-dimensional percolation model of flooding and snow ice formation on Antarctic sea ice. Journal of Geophysical Research, 105, 26 31326 331.CrossRefGoogle Scholar
Maksym, T. Jeffries, M.O. 2001. Phase and compositional evolution of the flooded layer during snow-ice formation on Antarctic sea ice. Annals of Glaciology, 33, 3744.CrossRefGoogle Scholar
Massom, R.A., Lytle, V.I., Worby, A.P. Allison, I. 1998. Winter snow cover variability on East Antarctic sea ice. Journal of Geophysical Research, 103, 24 83724 855.Google Scholar
Massom, R.A., Giles, A.B., Fricker, H.A., Warner, R.C., Legrésy, B., Hyland, G., Young, N. Fraser, A.D. 2010. Examining the interaction between multi-year landfast sea ice and the Mertz Glacier Tongue, East Antarctica: another factor in ice sheet stability? Journal of Geophysical Research, 115, 1055.Google Scholar
Maykut, G.A. Untersteiner, N. 1971. Some results from a time-dependent thermodynamic model of sea ice. Journal of Geophysical Research, 76, 24.CrossRefGoogle Scholar
Paige, R.A. 1966. Crystallographic studies of sea ice in McMurdo Sound, Antarctica. U.S. Naval Civil Engineering Laboratory, Technical Report R494, 31 pp.Google Scholar
Remy, J.-P., Becquevort, S., Haskell, T.G. Tison, J.-L. 2008. Impact of the B-15 iceberg “stranding event” on the physical and biological properties of sea ice in McMurdo Sound, Ross Sea, Antarctica. Antarctic Science, 20, 593604.Google Scholar
Rigsby, G. 1968. The complexities of the three-dimensional shape of individual crystals in glacier ice. Journal of Glaciology, 7, 233251.Google Scholar
Robinson, N.J. Williams, M.J.M. 2012. Iceberg-induced changes to polynya operation and regional oceanography in the southern Ross Sea, Antarctica, from in situ observations. Antarctic Science, 24, 514526.Google Scholar
Saenz, B.T. Arrigo, K.R. 2012. Simulation of a sea ice ecosystem using a hybrid model for slush layer desalination. Journal of Geophysical Research, 10.1029/2011JC007544.Google Scholar
Sanderson, T.J.O. 1988. Ice mechanics: risks to offshore structures. London: Graham & Trotman, 253 pp.Google Scholar
Sjölind, S.-G. 1985. Visco-elastic buckling analysis of floating ice sheets. Cold Regions Science and Technology, 11, 241246.Google Scholar
Stuart, A.W. Bull, C. 1963. Glaciological observations on the Ross Ice Shelf near Scott Base, Antarctica. Journal of Glaciology, 4, 399414.Google Scholar
Sturm, M., Morris, K. Massom, R. 1998. The winter snow cover of the west Antarctic pack ice: its spatial and temporal variability. Antarctic Research Series, 74, 118.Google Scholar
Tabata, T., Fujino, K. Aota, M. 1967. Studies of the mechanical properties of sea ice: the flexural strength of sea ice in situ . In Ôura, H., ed. Physics of snow and ice. Sapporo: Institute of Low Temperature Science, Hokkaido University, 539550.Google Scholar
Timco, G. Weeks, W. 2010. A review of the engineering properties of sea ice. Cold Regions Science and Technology, 60, 107129.Google Scholar
Tison, J.-L. Verbeke, V. 2001. Chlorinity/salinity distribution patterns in experimental granular sea ice. Annals of Glaciology, 33, 1320.Google Scholar
Treverrow, A., Budd, W.F., Jacka, T.H. Warner, R.C. 2012. The tertiary creep of polycrystalline ice: experimental evidence for stress-dependent levels of strain-rate enhancement. Journal of Glaciology, 58, 301314.Google Scholar
Weeks, W.F. 2010. On sea ice. Fairbanks, AK: University of Alaska Press, 664 pp.Google Scholar
Worster, M.G. Wettlaufer, J.S. 1997. Natural convection, solute trapping, and channel formation during solidification of saltwater. Journal of Physical Chemistry, B101, 61326136.Google Scholar