This chapter presents information on matters that affect the Antarctic environment and that describe the current state of the environment. The focus is on the AAT, because this is where Australia's activities are centred-although certain trends in the environment may relate to East Antarctica in general, or Antarctica as a whole. Also discussed are Australia's subantarctic island groups-Macquarie Island, and Heard Island and McDonald Islands-and the Southern Ocean.
Discussing every aspect of the Antarctic environment comprehensively is beyond the scope of this chapter. Instead, it reports on a number of selected indicators, some of which have long-term (more than one decade) data, and offer the best representation of current change in high-priority areas. The discussion identifies and considers environmental variables that are currently subject to pressures that are likely to become influential in the foreseeable future. This chapter aims to set a benchmark for future monitoring of environmental change and the outcomes of management actions by summarising indicators discussed in recently published scientific literature, as well as offering information on operational indicators that are relevant to running Australia's Antarctic program. Although only a limited number of sites are monitored regularly in the AAT, some results are representative of other areas in East Antarctica with similar ecological characteristics. Where appropriate, comparisons are made with events occurring in West Antarctica, where environmental change is proceeding at a faster rate than in the eastern part of the continent.