Abstract:
INDICATOR DEFINITION
The area of land occupied by buildings, tanks, other structures (eg cable trays, scientific apparatus, equipment housing, concrete pads and radomes), roads and aeronautical features at Australia's three Permanent Stations in Antarctica.
TYPE OF INDICATOR
There are three types of indicators used in this report:
1.Describes the CONDITION of important elements of a system;
... 2.Show the extent of the major PRESSURES exerted on a system;
3.Determine RESPONSES to either condition or changes in the condition of a system.
This indicator is one of: PRESSURE
RATIONALE FOR INDICATOR SELECTION
Changes of land use lead to changes in the condition of the environment. In Australia's Antarctic Territory much of the human activity is concentrated around the Stations and refuges which are bases for scientific research. Changes in the amount of infrastructure at these sites is a reflection of human activity. The area of land occupied by this infrastructure is one measure of the effect on the environment of human activity. The total area of land occupied by infrastructure at Casey, Davis and Mawson Stations is calculated for this indicator, as the major proportion of the infrastructure is located at these sites.
DESIGN AND STRATEGY FOR INDICATOR MONITORING PROGRAM
Surveying organised by the Australian Antarctic Division's Mapping Officer is carried out each summer in Australia's Antarctic Territory. This work enables regular updates to be made to the Australian Antarctic Data Centre's Permanent Stations GIS datasets. New features are added using ground survey data. Removed features are flagged and retained in the datasets but do not contribute to the area calculation.
Station Leaders are instructed to notify the Technical Contact for this Indicator if any of the following types of structure are erected, removed, moved or modified on station or in the local area of the station.
-buildings
-helipads
-road
-tanks (fuel, water) and bunding
-cable trays
-concrete pads
-radomes
-science (including meteorological) apparatus
-equipment housing external to the buildings
-wind power generators
-comms feeder lines
When such changes occur, Station Leaders are asked for the approximate dimensions of new structures or modifications, and these structures are marked for surveying at the next available opportunity.
RESEARCH ISSUES
It may be possible in the future to write a script to automate the calculation process.
LINKS TO OTHER INDICATORS
Determining areas from which structures in the AAT are visible is central to the indicator: Annual variations in the visibility 'footprint' of structures in the Australian Antarctic Territory. The areas occupied by the structures and the heights of the structures will influence their visibility. The Australian continental stations cover a significant portion of the area occupied by structures within the AAT and so the areas determined for this indicator will be influential. 
