Record Details

Record 1 of 1
Ice-Shelf Tidal Flexure and Subglacial Pressure Variations
NTRS Full-Text: Click to View  [PDF Size: 165 KB]
External Online Source: doi:10.1016/j.epsl.2012.11.008
Author and Affiliation:
Walker, Ryan T.(Pennsylvania State Univ., Dept. of Geosciences, University Park, PA, United States);
Parizek, Byron R.(Pennsylvania State Univ. at DuBois, Mathematics and Geoscience, DuBois, PA, United States);
Alley, Richard B.(Pennsylvania State Univ., Dept. of Geosciences, University Park, PA, United States);
Anandakrishnan, Sridhar(Pennsylvania State Univ., Dept. of Geosciences, University Park, PA, United States);
Riverman, Kiya L.(Pennsylvania State Univ., Dept. of Geosciences, University Park, PA, United States);
Christianson, Knut(Saint Olaf Coll., Dept. of Physics, Northfield, MN, United States)
Abstract: We develop a model of an ice shelf-ice stream system as a viscoelastic beam partially supported by an elastic foundation. When bed rock near the grounding line acts as a fulcrum, leverage from the ice shelf dropping at low tide can cause significant (approx 1 cm) uplift in the first few kilometers of grounded ice.This uplift and the corresponding depression at high tide lead to basal pressure variations of sufficient magnitude to influence subglacial hydrology.Tidal flexure may thus affect basal lubrication, sediment flow, and till strength, all of which are significant factors in ice-stream dynamics and grounding-line stability. Under certain circumstances, our results suggest the possibility of seawater being drawn into the subglacial water system. The presence of sea water beneath grounded ice would significantly change the radar reflectivity of the grounding zone and complicate the interpretation of grounded versus floating ice based on ice-penetrating radar observations.
Publication Date: Jan 01, 2013
Document ID:
20140009626
(Acquired Aug 12, 2014)
Subject Category: GEOSCIENCES (GENERAL)
Report/Patent Number: GSFC-E-DAA-TN9990
Document Type: Journal Article
Publication Information: Earth and Planetary Science Letters; Volume 361; 422-428
Publisher Information: Elsevier
Contract/Grant/Task Num: NNX12AD03A; NNX00AV94G; NNX10AD04G; NSF 0424589; NSF 0909335; NSF 0758274
Financial Sponsor: NASA Goddard Space Flight Center; Greenbelt, MD United States
Organization Source: NASA Goddard Space Flight Center; Greenbelt, MD United States
Description: 7p; In English; Original contains black and white illustrations
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright; Distribution under U.S. Government purpose rights; under NASA Cooperative Agreement NNX12AD03A
NASA Terms: VISCOELASTICITY; HYDROLOGY MODELS; FLEXING; LAND ICE; TIDAL FLATS
Other Descriptors: ICE-SHELF; SUBGLACIAL; TIDAL
› Back to Top
Facebook icon, External Link to NASA STI page on Facebook Twitter icon, External Link to NASA STI on Twitter YouTube icon, External Link to NASA STI Channel on YouTube RSS icon, External Link to New NASA STI RSS Feed
Find Similar Records
 
NASA Logo, External Link

NASA Official: Gerald Steeman

Sponsored By: NASA Scientific and Technical Information Program

Site Curator: STI Support Services

Last Modified: October 18, 2014

Privacy Policy & Important Notices Disclaimers, Copyright, Terms of Use Freedom of Information Act USA.gov NASA.gov NASA OCIO Free Adobe PDF Reader Free MS Word Viewer