Sökning: "Rickard Pettersson"

Hittade 5 avhandlingar innehållade orden Rickard Pettersson.

  1. 1. Dynamics of the cold surface layer of polythermal Storglaciären, Sweden

    Författare :Rickard Pettersson; Per Holmlund; Peter Janssson; Jens-Ove Näslund; Regine Hock; Helgi Björnsson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polythermal glacier; cold surface layer; ground-penetrating radar; spatial variability; water content; Storglaciären; Earth sciences; Geovetenskap;

    Sammanfattning : Polythermal glaciers, i.e. glaciers with a combination of ice at and below the freezing point, are widespread in arctic and subarctic environments. The polythermal structure has major implications for glacier hydrology, ice flow and glacial erosion. LÄS MER

  3. 2. Climatology and firn processes in the lower accumulation area of the Greenland ice sheet

    Författare :Charalampos Charalampidis; Veijo Pohjola; Dirk van As; Rickard Pettersson; Douglas Benn; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; climate change; Greenland ice sheet; accumulation area; automatic weather stations; surface energy balance; melt–albedo feedback; surface mass budget; snow; firn; meltwater; percolation; refreezing; runoff;

    Sammanfattning : The Greenland ice sheet is the largest Northern Hemisphere store of fresh water, and it is responding rapidly to the warming climate. In situ observations document the changing ice sheet properties in the lower accumulation area, Southwest Greenland. 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. Subsurface fluxes of mass and energy at the accumulation zone of Lomonosovfonna ice cap, Svalbard

    Författare :Sergey Marchenko; Veijo Pohjola; Rickard Pettersson; Carleen Reijmer; Thomas Schuler; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; glacier; ice sheet; sea level; runoff; ice; firn; snow; stratigraphy; density; core; radar; thermistor; temperature; preferential water flow; thermal conductivity; water content; Geovetenskap med inriktning mot naturgeografi; Earth Science with specialization in Physical Geography;

    Sammanfattning : Glaciers cover ca 10% of the Earth's land and are found in the high altitudes and latitudes. They are important components of environmental systems due to the multiple feedbacks linking them with the atmosphere, hydrosphere and periglacial landscapes. LÄS MER

  7. 5. Modelling calving and sliding of Svalbard outlet glaciers : Spatio-temporal changes and interactions

    Författare :Dorothée Vallot; Rickard Pettersson; Veijo Pohjola; Ken Mattsson; Tómas Jóhannesson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cryospheric science; glacier modelling; time-lapse imagery; undercutting; sliding inversion; discrete particle model; calving model; subglacial hydrology; sliding law; automatic detection method; calving events size and frequency; ocean interaction; melt water runoff; ice dynamics; ice flow model; Geovetenskap med inriktning mot naturgeografi; Earth Science with specialization in Physical Geography;

    Sammanfattning : Future sea level rise associated to global warming is one of the greatest societal and environmental challenges of tomorrow. A large part of the contribution comes from glaciers and ice sheets discharging ice and meltwater into the ocean and the recent worldwide increase is worrying. LÄS MER