Sökning: "ice sheet dynamics"

Visar resultat 1 - 5 av 24 avhandlingar innehållade orden ice sheet dynamics.

  1. 1. Computational Ice Sheet Dynamics : Error control and efficiency

    Författare :Josefin Ahlkrona; Per Lötstedt; Jesse Johnson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ice sheet modelling; stokes equations; shallow ice approximation; finite element method; perturbation expansions; non-newtonian fluids; free surface flow; Scientific Computing; Beräkningsvetenskap;

    Sammanfattning : Ice sheets, such as the Greenland Ice Sheet or Antarctic Ice Sheet, have a fundamental impact on landscape formation, the global climate system, and on sea level rise. The slow, creeping flow of ice can be represented by a non-linear version of the Stokes equations, which treat ice as a non-Newtonian, viscous fluid. LÄS MER

  3. 2. Palaeo-ice streams in the north-eastern Laurentide Ice Sheet

    Författare :Hernán De Angelis; Johan Kleman; Krister Jansson; Colm O'Cofaigh; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ice sheet; ice stream; palaeo-ice sheet; palaeo-ice stream; glaciology; palaeoglaciology; Laurentide Ice Sheet; Physical geography; Naturgeografi; geografi med naturgeografisk inriktning; Physical Geography;

    Sammanfattning : This thesis presents a palaeoglaciological study aimed to determine the location, geometry and temporal evolution of palaeo-ice streams of the north-easternmost Laurentide Ice Sheet. The work was accomplished through the geomorphological interpretation of satellite imagery over 3. LÄS MER

  4. 3. Hydrology and Bed Topography of the Greenland Ice Sheet : Last known surroundings

    Författare :Katrin Lindbäck; Rickard Pettersson; Francisco Navarro; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; climate change; Greenland Ice Sheet; radio-echo sounding; digital elevation models; ice thickness; bed topography; spectral analysis; roughness; subglacial hydrology; water piracy; englacial features; drainage catchments; meltwater runoff; ice dynamics; klimatförändringar; Grönlands inlandsis; markbaserad radar; digitala höjdmodeller; istjocklek; bottentopografi; spektralanalys; subglacial hydrologi; englaciala strukturer; avrinningsområden; isdynamik;

    Sammanfattning : The increased temperatures in the Arctic accelerate the loss of land based ice stored in glaciers. The Greenland Ice Sheet is the largest ice mass in the Northern Hemisphere and holds ~10% of all the freshwater on Earth, equivalent to ~7 metres of global sea level rise. LÄS MER

  5. 4. Numerical ice sheet modeling : Forward and inverse problems

    Författare :Gong Cheng; Lina von Sydow; Per Lötstedt; Nina Kirchner; Irina Tezaur; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; ice sheet modeling; finite element method; grounding line migration; inverse problems; adjoint method; Scientific Computing; Beräkningsvetenskap;

    Sammanfattning : Ice sheets have strong influence on the climate system. Numerical simulation provides a mathematical tool to study the ice dynamics in the past and to predict their contribution to climate change in the future. Large scale ice sheets behave as incompressible non-Newtonian fluid. LÄS MER

  7. 5. Late Quaternary ice sheet history and dynamics in central and southern Scandinavia

    Författare :Timothy Johnsen; Helena Alexanderson; James T. Teller; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Scandinavian ice sheet; ice sheet dynamics; luminescence dating; cosmogenic exposure dating; geochronology; moraine; interstadial; deglaciation; nunatak; Quaternary geology; Kvartärgeologi; kvartärgeologi; Quarternary Geology;

    Sammanfattning : Recent work suggests an emerging new paradigm for the Scandinavian ice sheet (SIS); one of a dynamically fluctuating ice sheet. This doctoral research project explicitly examines the history and dynamics of the SIS at four sites within Sweden and Norway, and provides results covering different time periods of glacial history. LÄS MER