18/10/2005
- Australia's summer of science in Antarctica gets underway
today as the research vessel Aurora Australis leaves on
the first voyage south.
The Minister for the Environment and Heritage, Senator
Ian Campbell, said two key projects on the voyage this
season were the Impact of Human Activities in Antarctica
near Casey station and the Amery Ice Shelf Ocean Research
(AMISOR) project inland from Davis station.
Senator Campbell said this would be the last year in which
Australia will be solely dependent on moving expeditioners
by sea to Antarctica. From next summer, Australia will
be trialling its new intercontinental air transport link
between Hobart and Antarctica. Scheduled flights are planned
to commence in late 2007.
Impact of Human Activities in Antarctica:
Senator Campbell said Australia would
use innovative new techniques to attempt the first full-scale
on-site oil spill clean-up in Antarctica - a significant
step towards cleaning up the poor practices of more than
two decades.
"It is estimated that throughout Antarctica there
are between one and 10 million cubic metres of contaminated
soil and waste. We can't be more exact because nobody
is entirely sure of the extent of the contamination,"
Senator Campbell said.
"What we do know is that in the past there was scant
regard for the effects on the environment of pollutants
such as fuel and other contaminants, and all types of
rubbish generated on Antarctic stations were simply tossed
away - sometimes onto the sea ice in the hope of it being
carried away. All countries with a presence in Antarctica
were equally guilty. However, since 1986, we have brought
our rubbish back from all the Australian Antarctic stations.
"In 1991 Australia led the world in providing comprehensive
protection to the Antarctic environment through the Madrid
Protocol - Australia now leads the way in cleaning up
Antarctica.
The Australian Antarctic Division's Head of the Impact
of Human Activities in Antarctica Programme, Dr Martin
Riddle, will lead the six-month project at Australia's
Casey station.
"There are two parts to this project - terrestrial
and marine," Dr Riddle said.
"On land we will test a new approach to remediating
the sites of past oil spills. The sheer volume of contaminated
material in Antarctica means it will never be possible
to return it all to the country of origin. We need to
be innovative if we are really to make a dent in this
problem.
"In the sea we will revisit sites as part of on-going
monitoring to ensure the success of the removal of 1000
cubic metres of waste material from Thala Valley tip near
Casey in 2004. The monitoring should confirm that removal
did not cause additional spread of contaminants. On the
contrary, we hope to document the start of recovery of
marine communities adjacent to the old tip.
"Most of our old tip sites were located on the foreshore
meaning there has been run-off into the surrounding waters.
So we are looking not only at cleaning up on-land contamination
but how that might also benefit the health of the marine
environment," Dr Riddle said.
Amery Ice Shelf Ocean Research:
Senator Campbell said six scientists would spend 12 weeks
on the Amery Ice Shelf where they will drill boreholes
through the ice to gain access to the seabed and the ocean
cavity beneath the floating shelf to gain a greater understanding
of global climate processes.
"The Amery Ice Shelf - the third largest ice shelf
in Antarctica - has been studied by the Australian Antarctic
programme in several campaigns over the past 50 years.
The current Amery Ice Shelf Ocean Research (AMISOR) project
was established in 1999 when the importance of ice-ocean
interaction became fully apparent," Senator Campbell
said.
Australian Antarctic Division glaciologist and leader
of the AMISOR project, Mike Craven, said that work was
continuing towards gaining a greater understanding of
the role of the Amery Ice Shelf in the ice sheet mass
budget and in driving ocean circulation.
"As much as 50 per cent of the total ice draining
from the Lambert Glacier system - the continent's largest
glacier system - melts at the base of the Amery within
the first hundred kilometres of becoming afloat. Some
of this later refreezes to the base of the shelf where
it is thinner further north," Mr Craven said.
"The modification of ocean water properties that
results from melting and freezing processes under ice
shelves may be important in the formation of Antarctic
Bottom Water and critical in global ocean circulation.
"We will use a hot water drill to bore two holes
through the ice shelf, one to a depth approaching 800
metres of ice thickness, several hundred metres deeper
than we have previously drilled.
"A range of instruments will be used to take short
ice cores at various levels, sediment samples, and to
collect data that will help in analysing ice-flow dynamics,
temperature, salinity, circulation beneath the shelf and
sea floor history. A video camera will also be lowered
through the bore holes to inspect ice characteristics
and the possibility of biological communities on the seabed."
Aurora Australis is scheduled to depart Hobart at 5pm
today. |