Advanced Search »
Newsletter
Unsubscribe »
National Science Foundation Award #0440899

Modeling the Dynamics of Surface-slope Reversals and their Role in the Formation and Stability of Subglacial Lakes

 
Investigator(s): Richard Alley (PI) ; Todd Dupont (Co-PI)
Sponsor: Pennsylvania State Univ University Park, PA 16802 8148654700
Start Date/Expiration Date 2005-01-01 to 2005-12-31 (amended 2004-12-08)
Awarded Amount to Date: $99,128
Abstract: This award supports a three-year modeling effort to understand the dynamics surrounding ice-air surface slope reversals on ice streams and ice shelves, with implications for the creation and stability of subglacial lakes. Local reversal of the ice-air surface slope may lead, through a reversal of the hydraulic gradient, to the trapping of basal and surface water, producing subglacial and supraglacial lakes, respectively. In the case of subglacial lakes, once such a sizable reservoir of pressurized water is created the potential exists for drainage, in the form of large outburst floods or as smaller, but sustained, periods of increased subglacial water flow. The research seeks to extend some initial work that has been done to include time-dependence and a wider array of parameters and geometries. The methods will involve the use of a suite of models, all of which will include longitudinal deviatoric and basal-shear stresses, with some also taking account of lateral drag and internal vertical shear. The intellectual merit of the proposed activity includes an improved understanding of the processes and parameters involved in the formation of surface-slope reversals in ice-stream/ice-shelf systems, as well as insight into the stability of subglacial lakes formed as a consequence of slope reversals. The broader impacts resulting from this activity include the provision of tools to study the dynamics of ice-stream/ice-shelf systems, an improved understanding of the physics behind outburst floods, and insights into the coupling of ice streams with their subglacial water systems. The research will support the studies of a beginning postdoctoral researcher. Results of the research will be incorporated into courses and public outreach serving anywhere from hundreds to thousands of people per year.
NSF Org: ANT - Antarctic Sciences Section
Award Number: 0440899
Award Instrument: Continuing grant
Program Manager: Julie Palais
ANT Antarctic Sciences Section
OPP Office of Polar Programs
NSF Program(s): ANTARCTIC GLACIOLOGY
Field Application(s): Polar Programs-Related
Program Reference Code(s): UNASSIGNED, 0000
Program Element Code(s): 5116