Reference : Enhanced basal lubrication and the contribution of the Greenland ice sheet to future ...
Scientific journals : Article
Physical, chemical, mathematical & earth Sciences : Earth sciences & physical geography
Enhanced basal lubrication and the contribution of the Greenland ice sheet to future sea-level rise
Shannon, S. []
Payne, A. []
Bartholomew, I. []
van den Broeke, M. []
Edwards, T. []
Fettweis, Xavier mailto [Université de Liège - ULiège > Département de géographie > Topoclimatologie >]
Gagliardini, O. []
Gillet-Chaulet, F. []
Goelzer, H. []
Hoffman, M. []
Huybrechts, Ph. []
Mair, D. []
Nienow, P. []
Perego, M. []
Price, S. []
Smeets, P. []
Sole, A. []
van de Wa, R. []
Zwinger, T. []
Proceedings of the National Academy of Sciences of the United States of America
National Academy of Sciences
Yes (verified by ORBi)
[en] We assess the effect of enhanced basal sliding on the flow and mass budget of the Greenland ice sheet, using a newly developed parameterization of the relation between meltwater runoff and ice flow. A wide range of observations suggest that water generated by melt at the surface of the ice sheet reaches its bed by both fracture and drainage through moulins. Once at the bed, this water is likely to affect lubrication, although current observations are insufficient to determine whether changes in subglacial hydraulics will limit the potential for the speedup of flow. An uncertainty analysis based on our best-fit parameterization admits both possibilities: continuously increasing or bounded lubrication. We apply the parameterization to four higher-order ice-sheet models in a series of experiments forced by changes in both lubrication and surface mass budget and determine the additional mass loss brought about by lubrication in comparison with experiments forced only by changes in surface mass balance. We use forcing from a regional climate model, itself forced by output from the European Centre Hamburg Model (ECHAM5) global climate model run under scenario A1B. Although changes in lubrication generate widespread effects on the flow and form of the ice sheet, they do not affect substantial net mass loss; increase in the ice sheet’s contribution to sea-level rise from basal lubrication is projected by all models to be no more than 5% of the contribution from surface mass budget forcing alone.
Researchers ; Students ; General public
FP7 ; 226375 - ICE2SEA - Ice2sea - estimating the future contribution of continental ice to sea-level rise

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