HR: 0830h
AN: C31C-0413 [PDF]
TI: Giant Tabular Icebergs as Surrogate Ice Shelves in Field Studies of Antarctica's Response to
Environmental Warming.
AU: * MacAyeal, D R
EM: drm7@midway.uchicago.edu
AF: Department of Geophysical, University of Chicago
5734 S. Ellis Ave., Chicago, IL 60637 United States
AU: Thom, J
EM: jonathan.thom@ssec.wisc.edu
AF: AMRC, Space Science and Engineering Center, University of Wisconsin
1225 W. Dayton St., Madison, WI 53706 United States
AU: Bliss, A
EM: abliss@seismo.berkeley.edu
AF: Department of Geography, University of California, Berkeley
507 McCone Hall, Berkeley, CA 94720 United States
AB:
The past 3 years have witnessed approximately 6000 km$^3$ of ice calved from the Antarctic ice sheet as a handful of
extremely large tabular icebergs in the Ross and Weddell Seas. Several of these icebergs are comparable to many of the
smaller, fringing ice shelves that surround the continent, and which have become the subject of concern since the recent
sudden break-up of Larsen B ice shelf on the Antarctic Peninsula. While the drift and melting of these giant icebergs over
the coming decades will undoubtedly have some impact on oceanic conditions beyond the Antarctic, the principal interest in
these great wandering ice masses is motivated by the "natural experiments" their evolution in response to northward drift
entails. In particular, the melting (both surficial and basal) and fragmentation of these icebergs in response to warmer
conditions encountered in the Southern Ocean beyond Antarctica may closely resemble the effects future climate change may
have on the stationary ice shelves along the coast of Antarctica.
In recognition of this opportunity, we have been maintaining a suite of instruments, including GPS, automatic weather
stations, ice-sounding sonars and seismometers on two icebergs in the Ross Sea (B15a and C16), and intend to place such a
suite on the Drygalski Ice Tongue in anticipation of it's future calving (to be performed in October, 2003). Our poster
summarizes the observations made so far, and discusses the potential for deploying new sensors and undertaking additional
field campaigns to examine how these icebergs will ultimately disintegrate.
DE: 1827 Glaciology (1863)
DE: 4540 Ice mechanics and air/sea/ice exchange processes
SC: Cryosphere [C]
MN: 2003 Fall Meeting