HR: 14:55h
AN: C33A-06    [Abstracts]
TI: Changes in Pine Island Glacier and Thwaites Glacier from GLAS (2003), ATM (2002) and ERS-1 (1995) Elevation Models and Questions of Stability of the West-Antarctic Ice Sheet
AU: * Herzfeld, U C
EM: herzfeld@iceberg.colorado.edu
AF: Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO 80309-0449 United States
AU: Thomas, R
C33A-06 AF: NASA Goddard Space Flight Center, Wallops Flight Facility, Wallops Island, VA 23337 United States
AU: Krabill, W
C33A-06 AF: NASA Goddard Space Flight Center, Wallops Flight Facility, Wallops Island, VA 23337 United States
AU: Zwally, J
C33A-06 AF: NASA Goddard Space Flight Center, Code 614.1, Greenbelt, MD 20771 United States
AU: DiMarzio, J
C33A-06 AF: NASA Goddard Space Flight Center, Code 614.1, Greenbelt, MD 20771 United States
AU: Manizade, S
C33A-06 AF: NASA Goddard Space Flight Center, Wallops Flight Facility, Wallops Island, VA 23337 United States
AU: McBride, P
C33A-06 AF: Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO 80309-0449 United States
AU: Casassa, G
C33A-06 AF: Centro de Estudios Cientificos, Avenida Arturo Prat, Valdivia, CO 99999 Chile
AU: Rivera, A
C33A-06 AF: Centro de Estudios Cientificos, Avenida Arturo Prat, Valdivia, CO 99999 Chile
AB: Pine Island Glacier and Thwaites Glacier are the two largest and fastest-flowing ice streams that drain the northern margin of the West Antarctic Ice Sheet in Ellsworth Land and Marie Byrd Land. Pine Island and Thwaites Glaciers are glaciologically important, because they play a significant role in scenarios of a possible break-up of the West Antarctic Ice Sheet. In recent years, Pine Island Glacier has undergone rapid changes, indicating that collapse may already be underway. Neighboring Thwaites Glacier moves even faster than Pine Island Glacier but exhibits only moderate changes. Time series of high-resolution elevation models, derived from satellite and airborne altimeter data using multivariate geostatistical methods, reveal new glaciologic insight in this rapidly changing part of the cryosphere and provide a greatly improved basis for modeling. Satellite laser altimeter data from ICESat provide new points in spatial time series for Pine Island Glacier, Thwaites Glacier, and Walgreen Coast, and are compared to and integrated with Airborne Topographic Mapper (ATM) data collected in 2002 and ERS-1/2 altimeter data collected in the last decade. The spatial distribution of surface lowering in Pine Island Glacier suggests an attribution of the changes to an internally forced process in the glacier. Thinning rates are larger than previously reported, which indicates an increase in the magnitude of changes in Pine Island Glacier.
DE: 0700 CRYOSPHERE (4540)
DE: 0728 Ice shelves
DE: 0758 Remote sensing
DE: 0774 Dynamics
DE: 0776 Glaciology (1621, 1827, 1863)
SC: Cryosphere [C]
MN: Fall Meeting 2005