15/03/2006
- Researchers returned to Australia this week after a comprehensive
10-week survey of the Southern Ocean, the Australian Minister
for the Environment and Heritage, Senator Ian Campbell, said
today.
The Baseline Research on Oceanography, Krill and the Environment
- or BROKE-West voyage - was led by the Australian Antarctic
Division (AAD) and the Antarctic Climate and Ecosystems Co-operative
Research Centre (ACE CRC) and covered more than a million
square kilometres of the Southern Ocean off Australia's Antarctic
Territory.
During the survey researchers found temperature and salinity
changes in some areas of the Southern Ocean as well as potential
new krill populations – the main food source for whales and
some seabirds.
"Researchers have found that deep
waters in part of the survey area were warmer and had higher
salinity levels than previously observed," Senator Campbell
said.
While most sectors of the survey area confirm earlier findings
of cooler Antarctic waters and less salinity, the easternmost
line of the survey showed an increase in both temperature
and salinity.
"This is possibly due to a convergence
of ocean fronts and a movement of currents south and our researchers
will undertake further analysis over the coming year to determine
why this has happened and what it means for ecosystems in
the region," Senator Campbell said.
"Researchers
on the voyage also confirmed the presence of a source of very
deep Antarctic waters – among the densest waters found on
earth.
"These waters, known as 'bottom waters', are
so named because they fill the abyssal ocean around Antarctica
and are important in carrying oxygen-rich waters and driving
global deep ocean circulation.
"A significant finding
of the survey was the potential discovery of a new population
of krill which is a very important food source for whales
and some seabirds," he said.
Researchers found that krill in the region was more widespread
when compared with other areas of East Antarctica, suggesting
there may be an oceanic population as well as a coastal population.
Senator Campbell said that BROKE-West had been one of the
most comprehensive surveys ever undertaken and would provide
answers on a whole range of issues and assist with future
planning initiatives for the Southern Ocean.
"This
has been a great effort by the Australian agencies and a marvellous
example of collaboration between 62 scientists from 14 countries,"
Senator Campbell said.
The completion of this survey is the culmination of a 10-year
project which means that most waters off the Australian Antarctic
Territory have now been investigated by the Australian Government's
$100 million a year Antarctic Programme. |
