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Publications archive - Annual reports

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Key departmental publications, e.g. annual reports, budget papers and program guidelines are available in our online archive.

Much of the material listed on these archived web pages has been superseded, or served a particular purpose at a particular time. It may contain references to activities or policies that have no current application. Many archived documents may link to web pages that have moved or no longer exist, or may refer to other documents that are no longer available.

Environment Australia Annual Report 2001-02

Environment Australia, 2002
ISSN 1441-9335

Review of Performance - Outcome Three: Antarctica (continued)
Understanding Antarctica's Role in the Global Climate System (Departmental Output 3.3)

Objective

The AAD seeks a better understanding of the role of Antarctica in the global climate system by contributing to knowledge of global climate through the study of ice, water and atmosphere, and contributing data to the world's climate research and meteorological communities.

Result


Atmospheric sciences

Lidar equipment and optical spectrophotometers and radars were operated at Davis station, measuring stratospheric and mesospheric properties to quantify temperature, wind and aerosol concentration to determine their role in the middle atmosphere climate.

Biology

Further work has confirmed that most bacteria in the Southern Ocean are dead or metabolically inactive. Trials of a new aquarium based experimental system at sea were an outstanding success. Primary production, bacterial production and the production of oxygen and reduced sulphur compounds were measured. This new approach will be critical in understanding marine microbial processes and the organisms involved.

Primary and bacterial production estimates were found to be closely coupled on a transect across the Southern Ocean, with the sub-Antarctic zone being much more productive than waters to the south. The sub-Antarctic front-polar front boundary is the oceanographic feature separating the regions of high and low productivity.

The melting sea ice in the Prydz Bay region was found to be a significant source of reduced sulphur compounds. Scientists found that ultra violet radiation causes a reduction in photosynthesis and growth of sea ice algae of 5 to 10 per cent. These algae are extremely shade adapted but adapt to changes in irradiance remarkably quickly.

Glaciology

The mass of different sectors of East Antarctica was assessed using field and remote sensing measurements and models. High- and low-resolution records of ice core chemistry covering the last 1000 years were produced. About 100 000-year stable isotope proxy record of climatic temperatures at Law Dome was dated by trapped gas and other measurements providing information on changes in past climates.

New remote sensing, field observational and model results have considerably narrowed the uncertainty about the stability of the Antarctic ice sheet, in particular of East Antarctica and of the Lambert Glacier drainage basin. This information enhances understanding of how ice and water in Antarctica interact. A second hot water drill hole was made through nearly 500 metres of the Amery Ice Shelf to investigate these processes in the ocean cavity beneath.

High resolution measurements of stable isotopes, trapped gas and ice chemistry on the Law Dome ice core have shown the independence of significant Southern Ocean cooling events from similar northern hemisphere (North Atlantic) events.

Oceanography

The Mertz Glacier polynya (open water) study was completed and the first manuscripts of results were published.