Show simple item record

dc.contributor.authorvan der Veen, Cornelis J.
dc.contributor.authorPlummer, J. C.
dc.contributor.authorStearns, Leigh A.
dc.date.accessioned2015-04-02T16:57:53Z
dc.date.available2015-04-02T16:57:53Z
dc.date.issued2011-02-05
dc.identifier.citationVanderveen, C. J., Plummer, J. C., Stearns, L. A. "Controls on the recent speed-up of Jakobshavn Isbrae, West Greenland." (2011) Journal of Glaciology. 57, 204. pp 770 - 782. http://dx.doi.org/10.3189/002214311797409776.en_US
dc.identifier.urihttp://hdl.handle.net/1808/17291
dc.descriptionThis is the published version, also available here: http://dx.doi.org/10.3189/002214311797409776.en_US
dc.description.abstractJakobshavn Isbrae, West Greenland, underwent a large, rapid and not well understood change in flow dynamics in 1998, leading to a doubling of its ice discharge rates. We calculate the width-averaged forces controlling flow of Jakobshavn Isbrae in 1995, 2000 and 2005 to elucidate processes responsible for this change in flow speed. In contrast to earlier suggestions, we conclude that the observed acceleration was not caused by the loss of back-stress due to weakening and subsequent break-up of the floating ice tongue alone. Gradients in longitudinal stress are small at all times considered (∼3% of the driving stress) and basal and lateral drag provide resistance to flow. Over the 10 year period considered, the average driving stress increased by 20 kPa, which was balanced by a comparable increase in lateral drag. We surmise that the velocity changes resulted from weakening of the ice in the lateral shear margins and perhaps a change in properties at the bed. Possible mechanisms for weakening of ice in the lateral shear margins include cryo-hydrologic warming of subsurface ice in the ablation zone and hydraulic weakening due to higher water content of ice in the shear margins.en_US
dc.publisherInternational Glaciological Societyen_US
dc.titleControls on the recent speed-up of Jakobshavn Isbrae, West Greenlanden_US
dc.typeArticle
kusw.kuauthorvan der Veen, Cornelis J.
kusw.kudepartmentGeographyen_US
dc.identifier.doi10.3189/002214311797409776
kusw.oaversionScholarly/refereed, publisher version
kusw.oapolicyThis item meets KU Open Access policy criteria.
dc.rights.accessrightsopenAccess


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record