Numerical simulations of major ice streams in western Dronning Maud Land, Antarctica, under wet and dry basal conditions

• Published in: Journal of Glaciology
• Main Authors: Kleiner, Thomas, Humbert, Angelika
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: INT GLACIOL SOC 2014
• Subjects: Dronning Maud Land; Weertman; Antarc*; Antarctica; Journal of Glaciology
• Online Access: https://epic.awi.de/id/eprint/35753/; https://epic.awi.de/id/eprint/35753/1/s2.pdf; http://www.igsoc.org/journal/60/220/t13J006.html; https://hdl.handle.net/10013/epic.43683; https://hdl.handle.net/10013/epic.43683.d001

We study the presence and effect of subglacial water on the motion of the inland ice in western Dronning Maud Land. A full-Stokes model including three routing schemes for a thin film of subglacial water and a modification of a Weertman-type sliding relation to account for higher sliding velocities under wet basal conditions were used to perform 200 ka spin-up simulations on a 2.5 km grid. Subsequent 30 ka simulations with wet and dry basal conditions were analysed for the effects of sliding on the thermal regime and velocities. The occurrence of the major ice streams in this area is mainly controlled by the ice and bedrock geometry. Smaller glaciers only appear as pronounced individual glaciers, when subglacial water is taken into account. The thermal regime is affected by creep instabilities produced by an ice rheology including a microscopic water content, leading to a cyclic behaviour on millennial time scales of the ice flow and occurrence of temperate ice at the base.