HR: 14:55h
AN: C22A-06    [PDF]
TI: Outburst Flooding and Surge Initiation
AU: * Alley, R B
EM: ralley@essc.psu.edu
AF: Department of Geosciences and EMS Environment Institute, Pennsylvania State University, Deike Building, University Park, PA 16802 United States
AU: Dupont, T K
EM: dupont@essc.psu.edu
AF: Department of Geosciences and EMS Environment Institute, Pennsylvania State University, Deike Building, University Park, PA 16802 United States
AU: Parizek, B R
EM: parizek@essc.psu.edu
AF: Department of Geosciences and EMS Environment Institute, Pennsylvania State University, Deike Building, University Park, PA 16802 United States
AU: Anandakrishnan, S
EM: sak@essc.psu.edu
AF: Department of Geosciences and EMS Environment Institute, Pennsylvania State University, Deike Building, University Park, PA 16802 United States
AU: Lawson, D E
EM: dlawson@crrel.usace.army.mil
AF: Cold Regions Research and Engineering Laboratory, 72 Lyme Road, Hanover, NH 03755 United States
AU: Larson, G J
EM: larsong@pilot.msu.edu
AF: Department of Geological Sciences, Michigan State University, Geological Sciences Building, East Lansing, MI 48824 United States
AU: Evenson, E B
EM: ebe0@lehigh.edu
AF: Department of Earth and Environmental Sciences, Lehigh University, 31 Williams, Bethlehem, PA 18015 United States
AB: Antarctic subglacial lakes are well-known, and published geomorphic evidence from Pine Island Bay and from the Transantarctic Mountains suggests outburst flooding from subglacial lakes at different times in the past. Sedimentary evidence also indicates that abundant meltwater was involved in Heinrich events from Hudson Strait despite cold conditions, suggesting outburst flooding. Trapping of subglacial water is favored by development of a locally reversed ice-air surface slope, and by freeze-on; either may be sufficient singly, and both together should be sufficient. A cycle of ice-shelf grounding, freeze-on and development of slope reversal, thickening, thawing, and outburst flooding explains many observations, and is consistent with new modeling and with a range of observations from ice streams and ice shelves, although the ice-shelf step is not a necessary prerequisite.
DE: 1600 GLOBAL CHANGE (New category)
DE: 1827 Glaciology (1863)
DE: 1863 Snow and ice (1827)
DE: 3344 Paleoclimatology
SC: Cryosphere [C]
MN: 2003 Fall Meeting