HR: 10:35h
AN: C22A-02    [Abstracts]
TI: Combining ICESat and Aircraft Laser Altimetry Observations to Examine Recent Changes in Canadian Ice Caps
AU: * Abdalati, W
EM: waleed@icesat2.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Oceans and Ice Branch, Greenbelt, MD 20771 United States
AU: Krabill, W
EM: krabill@osb.wff.nasa.gov
AF: NASA Wallops Flight Facility, Observational Science Branch, Wallops Island, VA 23337 United States
AU: Thomas, R
EM: robert.thomas@hotmail.com
AF: EG&G, NASA Wallops Flight Facility Code 972, Wallops Island, VA 23337 United States
AU: Golder, J
EM: golder@pop500.gsfc.nasa.gov
AF: SIGMA, NASA Goddard Space Flight Center Code 971, Greenbelt, MD 20771 United States
AU: Frederick, E
EM: earlb@osb1.wff.nasa.gov
AF: EG&G, NASA Wallops Flight Facility Code 972, Wallops Island, VA 23337 United States
AU: Manizade, S
EM: manizade@osb.wff.nasa.gov
AF: EG&G, NASA Wallops Flight Facility Code 972, Wallops Island, VA 23337 United States
AU: Martin, C
EM: martin@osb.wff.nasa.gov
AF: EG&G, NASA Wallops Flight Facility Code 972, Wallops Island, VA 23337 United States
AB: Precise repeat airborne laser surveys were conducted over the major ice caps in the Canadian Arctic Archipelago during the spring of 1995 and 2000 to measure elevation changes in the region. Our observations reveal thinning at lower elevations (below 1600 m) on most of the ice caps and glaciers, but either very little change or thickening at higher elevations in the ice cap accumulation zones. The behavior of the ice caps in the north on the Queen Elizabeth Islands can be explained by recent temperature and precipitation anomalies, but this is not the case for the more southern ice caps on Baffin Island, which appear to be still shrinking in response to the Little Ice Age. The regional characteristics of elevation change as a function of elevation enables an assessment of the Canadian ice caps' contribution to sea level during the 1995-2000 time period. Our estimates place them among the more significant sources of eustatic sea level rise, though they are not as substantial as Greenland ice sheet, Alaskan glaciers, or the Patagonian ice fields. The spring 2004 campaign of the Ice Cloud and land Elevation Satellite (ICESat) mission provides a means of examining the character of changes since 2000. Comparisons between the ICESat data and the earlier aircraft campaigns where the ICESat ground tracks intersect the aircraft flight lines reveal significant changes in ice cap behavior between the late 1990s and the last four years. The results of these comparisons will be discussed along with the differences in the 1995-2000 and 2000-2004 climate conditions that affect the mass balance and elevation characteristics in those time periods.
DE: 1699 General or miscellaneous
DE: 1827 Glaciology (1863)
DE: 1863 Snow and ice (1827)
DE: 1640 Remote sensing
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting