par Hubbard, Bryn;Philippe, Morgane ;Tison, Jean-Louis ; [et al.]
Référence Nature communications, 7, page (11897)
Publication Publié, 2016-06-10
Article révisé par les pairs
Résumé : Surface melt ponds form intermittently on several Antarctic ice shelves. Although implicatedin ice-shelf break up, the consequences of such ponding for ice formation and ice-shelfstructure have not been evaluated. Here we report the discovery of a massive subsurface icelayer, at least 16 km across, several kilometres long and tens of metres deep, located in anarea of intense melting and intermittent ponding on Larsen C Ice Shelf, Antarctica. Wecombine borehole optical televiewer logging and radar measurements with remote sensingand firn modelling to investigate the layer, found to be ~10°C warmer and ~170 kg/m³ denser than anticipated in the absence of ponding and hitherto used in models of ice-shelffracture and flow. Surface ponding and ice layers such as the one we report are likely to formon a wider range of Antarctic ice shelves in response to climatic warming in forthcomingdecades.