Australian Antarctic Science Season 2009–10

Many scientific research projects will be conducted at Davis this season and during a marine science voyage between December and January. Casey station and Wilkins Runway will see significant infrastructure work in support of the Airlink, while a rabbit and rodent eradication program and long-term environmental monitoring will continue on Macquarie Island. This summary provides a snap-shot of some of the science activities this season. Other projects not mentioned here are listed on the map of Antarctic science projects 2009–10 [PDF].

Mawson

Adélie penguin monitoring: A long-term monitoring program of Adélie penguins is conducted on Béchervaise Island each summer to provide information required by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) for the sustainable management of the krill fishery.

Atmospheric research: A range of atmospheric research projects are conducted at Mawson each year and the results feed into climate research and models. Projects include looking at vertical mixing of the atmosphere above 100km altitude, which could play a role in coupling the upper atmosphere to Earth’s weather and climate; and observing small-scale upper-atmospheric wind and weather systems, and monitoring their response during auroral and magnetic storms.

Davis

The Amery Ice Shelf Ocean Research (AMISOR) project is the major field project at Davis this season. AMISOR is part of a broad umbrella study of the entire Lambert Glacier Basin–Amery Ice Shelf system, to understand both the climatic history of the region and its probable response to global warming. The project has been running since 2000 and involves hot water drilling of four boreholes through the ice shelf to measure ocean characteristics, ocean currents and basal melting and freezing processes. Freezing processes produce marine (jade) ice attached to the base of the ice shelf, which is permeable at depth and therefore vulnerable to changes in ocean properties beneath the shelf. The project is closely linked with a systematic seismic survey of the north-central shelf region and monitoring of the ‘Loose Tooth’ — a series of developing rifts at the front of the shelf that will lead to an iceberg calving event. Data from the research feeds into coupled ice shelf-ocean models that predict the patterns of melting and freezing at the base of the shelf, the modifications to water masses circulating below the shelf, and examine the way iceberg-forming rifts propagate into the body of the shelf. Previous research findings have been reported in Australian Antarctic Magazine 12: 32–33, 2007.

Atmospheric research: A new $270 000 laser for the Light Detection and Ranging (LIDAR) instrument will be installed at Davis this year. The new laser will enable the gathering of more detailed information on aerosol particles in the lower atmosphere. The LIDAR is used to measure atmospheric density, temperature, wind speed and aerosols from the ground to the edge of space. This season the LIDAR, in combination with radar, will be used to probe ice-aerosol cloud formations in the mesosphere (85km altitude). In the Arctic, these ice clouds are occurring more frequently and over a greater area than in the past. Australian scientists aim to determine whether similar changes are occurring over Antarctica and to examine the properties of these ice-aerosols. Changes in the properties of mesosphere ice-aerosol clouds may be linked to human activities or anthropogenic climate change.

Environmental monitoring of the Davis sewage outfall: Untreated, macerated sewage effluent is currently discharged to the sea at Davis, after the breakdown of the secondary wastewater treatment plant. This project will undertake environmental assessments in support of the planned installation of new sewage treatment facilities at Davis. A multitude of other marine ecology projects will feed into this work including:

  • Trophic ecology of the near-shore zone: ‘TRENZ’ aims to understand the structure and function of the food web in coastal, benthic (sea floor) communities in Antarctica, and their response to human activities and climate change, so as to better manage and protect them and the broader environment. Work this season will look at the effect of sewage on food webs (such as changes in the number or type of organisms in benthic communities) and uptake of sewage nutrients by marine organisms.
  • Developing sediment and water quality guidelines for Antarctica: It is generally thought that Antarctic organisms are highly sensitive to pollution, but there is little data to support or disprove this. This project will look at the effects of common contaminants, such as petroleum hydrocarbons, metals and sewage effluents, and their interactions with climate change variables, including temperature and salinity, on a range of Antarctic organisms; from micro-algae to macro-invertebrates. From this work, risk assessment techniques and environmental guidelines for the protection and remediation of sites will be developed.
  • Change in near-shore benthic communities: This project is investigating natural variability in coastal, benthic ecosystems; the impact of contaminants on them; and biological responses to human activity. The work will lead to improved bio-monitoring and development of an appropriate design system for near-shore marine protected areas.
  • Antibiotic resistance is common in bacteria associated with humans and is often used to identify sources of environmental contamination. This project will track the dissemination of antibiotic resistance genes in bacteria collected from sewage, sediment, ice and marine invertebrates around the Davis sewage outfall, and wider environment.
  • Contamination impacts on boulder communities: This project will look at the ecotoxicological effect of contaminated sediments on the growth, survival and recruitment of marine plants and animals living on hard substrates (particularly boulders) in the sediment at Davis. The work will contribute to the development of sediment quality guidelines for Antarctica.

Emperor penguins: This season scientists will deploy satellite trackers on emperor penguin fledglings to monitor the birds’ location and diving activities, to see how they change over time (about four months). As mortality is very high in the first year of life only the fattest chicks, and therefore the most likely to survive, will be tracked. Previous tracking work has shown that fledgling emperor penguins travel enormous distances (Australian Antarctic Magazine 15: 11, 2008) and pass several other emperor penguin colonies. Scientists will collect genetic material from dead chicks for DNA analysis, to see whether different populations of penguins interbreed and how similar or dissimilar emperor penguins are in other parts of Antarctica.

Casey

Remediation projects: These include ongoing research into the cost-effective clean up of petroleum spills in the Antarctic and other cold regions, and development and application of technologies to clean up heavy metal contaminants from abandoned waste disposal sites.

Whale observations: Some aerial observations will be conducted from a base in the Bunger Hills, while other work will be undertaken on the RV Tangaroa through the Southern Ocean Research Partnership.

ICECAP: The second field season for ‘Investigating the Cryospheric Evolution of the Central Antarctic Plate’ (ICECAP) will see an instrumented aircraft flying survey lines to probe the structure of the ice and underlying geology of the Aurora Subglacial Basin and Law Dome and Totten Glaciers, near Casey. The aircraft will also fly survey lines from McMurdo Station and Dumont d'Urville.

Macquarie Island

Environmental change: A number of projects are looking at how subantarctic organisms and ecosystems respond to change caused by global warming, feral animals and weedy plant species. The work will contribute to the conservation and restoration of the island once the feral animals have been removed. Researchers are also investigating why an endemic cushion plant appears to be suffering from a rapid die back on the plateau of the island.

Rabbit and rodent eradication: Helicopter pilots and sharpshooters are being recruited for the aerial baiting program and on-ground hunting of rabbits and rodents, while dogs (springer spaniels and labradors) are being trained to detect and flush out remaining rabbit survivors. The Antarctic Division is providing logistic support to this Tasmanian Government-run program. Details are available through the Tasmanian Parks & Wildlife Service.

Fuel spill remediation: Low-risk, low-cost, on-site remediation techniques are being used to clean up fuel spills at three sites by 2014. Risk assessment guidelines and target hydrocarbon levels for remediation are also being developed. Full details are reported in Australian Antarctic Magazine 16: 21, 2009.

Fur seals: This project is providing key information on the status and trends of recovering fur seal populations in the Southern ocean, including information on the distribution of foraging effort, food and energy requirements and interactions with commercial fisheries.

Marine Science

Benthic trawls: Benthic (sea-bed) trawls will be conducted off the East Antarctic coast (near Davis) to understand the impact of bottom fishing gear (longline, trawl and traps) on different habitat types. This will include identifying the characteristics of benthic communities vulnerable to bottom fishing, for use in modelling the effects of fishing. Images taken by trawl-mounted video and still cameras will be used to develop habitat maps and capture footage of the trawl-benthos interactions. The work will assist both Australia and the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) to manage high latitude fisheries, including the development of mitigation strategies, such as avoidance of an area or gear modifications. The specially developed camera technology is designed for easy deployment during commercial fishing operations.

Sea ice research will be conducted by an international team from Australia, Canada and France. An airborne sea ice thickness survey, from the ice edge to the continent, will be undertaken using a helicopter (from the ship) equipped with: a scanning light detection and ranging (LIDAR) system, to measure sea ice ‘freeboard’ (height above the ocean surface); a medium format digital still camera to measure floe size and surface characteristics; and an infra-red pyrometer for ‘skin surface’ (snow, ice and open water) temperature measurements. The data will be used for satellite calibration and validation and will continue a record of airborne sea ice measurements in the East Antarctic.

A second project will test a safety feature for operation of the Memorial University of Newfoundland Explorer class Autonomous Underwater Vehicle (AUV), for its planned missions under the Antarctic sea ice. The ‘beacon system’ provides an acoustic ‘heartbeat’ during normal operation; warns of a major fault; and uses a range-meter for emergency location. During under-ice operations the AUV will carry an upward looking sonar, to map the underside of sea ice; a hyper-spectral radiometer for measuring light passing through the ice and snow cover (under-ice irradiance); and a fish echo sounder to detect the presence of fish.

Other marine science projects include: mapping of plankton biodiversity with a continuous plankton recorder; studying the response of zooplankton to ocean acidficiation; and measuring the westward recirculation of the subpolar gyre of the south-eastern Indian Ocean — to monitor changes in this important ocean current and determine their implications.

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