Blar i forfatter "Pettersson, Rickard"

Viser treff 1-3 av 3

    • Cascading lake drainage on the Greenland Ice Sheet triggered by tensile shock and fracture 

      Christoffersen, Poul; Bougamont, Marion; Hubbard, Alun; Doyle, Samuel H.; Grigsby, Shane; Pettersson, Rickard (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-14)
      Supraglacial lakes on the Greenland Ice Sheet are expanding inland, but the impact on ice flow is equivocal because interior surface conditions may preclude the transfer of surface water to the bed. Here we use a well-constrained 3D model to demonstrate that supraglacial lakes in Greenland drain when tensile-stress perturbations propagate fractures in areas where fractures are normally absent or ...

    • Extraordinary runoff from the Greenland ice sheet in 2012 amplified by hypsometry and depleted firn retention 

      Mikkelsen, A.B.; Hubbard, Alun Lloyd; MacFerrin, Mike; Box, Jason Eric; Doyle, Sam H.; Fitzpatrick, Andrew; Hasholt, Bent; Bailey, Hannah L.; Lindbäck, Katrin; Pettersson, Rickard (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-05-30)
      It has been argued that the infiltration and retention of meltwater within firn across the percolation zone of the Greenland ice sheet has the potential to buffer up to  ∼  3.6 mm of global sea-level rise (Harper et al., 2012). Despite evidence confirming active refreezing processes above the equilibrium line, their impact on runoff and proglacial discharge has yet to be assessed. Here, we compare ...

    • Seismic evidence for complex sedimentary control of Greenland Ice Sheet flow 

      Kulessa, Bernd; Hubbard, Alun Lloyd; Booth, Adam D.; Bougamont, Marion; Dow, Christine F.; Doyle, Samuel H.; Christoffersen, Poul; Lindbäck, Katrin; Pettersson, Rickard; Fitzpatrick, Andrew A.W.; Jones, Glenn A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-16)
      The land-terminating margin of the Greenland Ice Sheet has slowed down in recent decades, although the causes and implications for future ice flow are unclear. Explained originally by a self-regulating mechanism where basal slip reduces as drainage evolves from low to high efficiency, recent numerical modeling invokes a sedimentary control of ice sheet flow as an alternative hypothesis. Although ...