United States - International Trans Antarctic Scientific Expedition
From its original formulation in 1990, the International Trans Antarctic
Scientific Expedition (ITASE) has had as its primary aim the collection and
interpretation of a continental- wide array of environmental parameters
assembled through the coordinated efforts of scientists from several nations.
The primary planned product of this cooperative endeavor is the description and
understanding of environmental change in Antarctica over the last ~200 years.
As a demonstration of the importance of the original scientific objectives
posed by ITASE, they were adopted as a key science initiative by both the
International Geosphere-Biosphere Program (IGBP) and the Scientific Committee
on Antarctic Research (SCAR).
In May 1996 a workshop sponsored by the National Science Foundation was held to
develop a Science and Implementation Plan for the United States contribution to
ITASE (called "US ITASE"). Because of the long-standing US research effort in
West Antarctica, US ITASE chose to focus its activities in this region. At the
US ITASE Workshop, participants developed a multi-disciplinary research plan
that integrates meteorology, remote sensing, ice coring and surface glaciology,
and geophysics through a four-phase approach. In Phase 1 meteorological
modeling and remote sensing will be used to plan sampling strategies conducive
to the major objectives of US ITASE. Phase 2 will involve ground-based sampling
over four study areas (corridors). Although a broad spatial sampling of West
Antarctica is proposed during Phase 2, it is expected that the logistic
requirements for this sampling will be modest and highly efficient. Phase 3
allows for the continuation of ground-based sampling at a limited number of key
sites where monitoring is required. Phase 4 is interpretation and modeling.
In its entirety, ITASE incorporates a wide range of general scientific
objectives. Those which are specific to US ITASE address the following
1. What is the current rate of change in mass balance over West Antarctica?
2. What is the influence of major atmospheric circulation systems (e.g., ENSO)
and oceanic circulation on the moisture flux over West Antarctica?
3. How does climate (eg., temperature, accumulation rate, atmospheric
circulation) vary over West Antarctica on seasonal, interannual, decadal and
centennial scales, and what are the controls on this variability?
4. What is the frequency, magnitude and effect (local to global) of any extreme
climate events recorded in West Antarctica?
5. What is the impact of anthropogenic activity (e.g., ozone depletion,
pollutants) on the climate and atmospheric chemistry of West Antarctica?
6. How much has biogeochemical cycling of S, N and C, as recorded in West
Antarctica, varied over the last 200+ years?
US ITASE provides an important spatial perspective for the shared research
goals of a variety of research programs funded by the NSF, NASA and NOAA.
Notably, questions 1-4 parallel closely themes identified by NSF's WAIS (West
Antarctic Ice Sheet) intiative. It is expected that these overlaps of
scientific purposes will make possible an efficient utilization of logistic
resources in the execution of these linked research programs.
A series of specific US ITASE products is proposed for the tentatively
scheduled 1997-2007 duration of this research effort. These products will
provide direct benefit to national scientific efforts as noted as well as
internationally based science programs developed through SCAR and IGBP. In
order to further this goal, this report was presented to the international
representatives attending the jointly sponsored GLOCHANT (SCAR) and PAGES
(IGBP) ITASE Workshop in Cambridge, England in August 1996. It is expected that
by the integration of US ITASE with the ITASE activities of other countries,
major contributions will be made to our understanding of Antarctica's role in