TL: SCIENCE PROGRAMME - GREENPEACE POLAR MELTDOWN TOUR, JANUARY
1997
SO: GREENPEACE INTERNATIONAL, (GP)
DT: JANUARY, 1997
 
During the Antarctic Tour, Greenpeace will be conducting a
science programme to contribute to research on the impacts
of climate change on the Antarctic region.  These projects
are being done collaboratively with research scientists from
Australia and Argentina by Greenpeace scientist Lic. Ricardo
Roura, who has been involved in Greenpeace's scientific work
in Antarctica (including the monitoring of the environmental
impact of World Park Base) since 1990.
 
 
1. RECENT PROCESSES OF MARINE SEDIMENTATION IN THE NW
WEDDELL SEA
 
Ice shelves are important in controlling and stabilizing the
discharge of ice from the Antarctic continent.  The northern
end of the Larsen Ice Shelf collapsed in 1995 exposing open
waters in an area of approximately 2,500km2.  Researchers
from the Argentine Antarctic Institute (IAA) have been
studying the Larsen Ice Shelf for the past 20 years,
including the part of the ice shelf that is now an open
expanse of water.  They believe that the recent warming of
the Antarctic Peninsula may be the cause of this collapse
(which has also occured recently in other smaller ice
shelves), and that other ice shelves may follow.
 
The research programme involves a study of the sea bed
morphology and recent processes of marine sedimentation in
the NW Weddell Sea, offshore the Larsen Ice Shelf.  The
marine biota of the water column (previously under ice) will
also be studied.  The new data will add to the body of
research preceeding the ice shelf collapse and contribute to
the understanding of the causes and consequences of the
collapse.
 
The field work will include a preliminary bathymetry (seabed
geography) survey of the area (which has not yet been
navigated and remains uncharted) and sampling of sediments
and plankton.  Shallow cores of sediments from the sea bed
surface will be extracted using a piston corer.  Plankton
samples will be taken concurrently.
 
The field work will be carried out jointly by researchers
from Greenpeace and the Argentine Antarctic Institute on
board the MV Arctic Sunrise.
 
2. ICE OBSERVATIONS
 
Icebergs
 
Monitoring the calving of icebergs provides information on
the thinning and fracturing of ice shelves and their
contribution to the mass balance of Antarctic ice.
Knowledge of the mass balance of Antarctica is important in
the determination of whether the Antarctic ice mass is
likely to contribute to sea level rise in the future.
 
Sea ice
 
The Antarctic sea ice cover is one of the most climatically
important features of the Southern Hemisphere, as it plays
an important role in oceanic heat flux and lower atmosphere
temperature.  Some climate models of greenhouse warming have
suggested that the warming would be greatest in polar
regions (others have suggested the opposite -- that warming
would be the least in the polar regions).  On a regional
basis, the correlation between temperatures and decreased
sea ice extent have been shown to be significant.
 
Sea ice concentration, extent and thickness are potential
indicators of climate change.  Systematic observations of
these parameters will be carried out throughout the trip.
The current sea ice database from similar observations
focuses on winter sea ice: there is less information
available on summer sea ice.
 
Throughout the trip, ship-based iceberg and sea ice
observations will be carried out to collect data for
researchers from Australia's Antarctic Cooperative Research
Centre.
 
Due to large regional and interannual variability, the
success of observation-based programmes depends on a large
database.  Greenpeace's observations will contribute to
research carried out in this field.
 
END