For many people, the state of the atmosphere is a measure of the state of the environment, and in Australia the immediate impression is good. Because of its isolation, air quality in Australia is not substantially influenced from outside its borders and, apart from the effects of bushfires, dust storms and localised industrial pollution, outdoor air quality in Australia’s cities continues to improve and usually meets agreed national standards. The quality of indoor air is unknown due to a lack of data, but bans on smoking in public places by most jurisdictions hold promise.
Australia is meeting its global responsibilities in reducing its consumption of ozone-depleting substances. The benefits of this global action can be seen in the increase in the amount of ozone in the upper atmosphere in recent years. The size of the hole in the ozone layer over Antarctica appears to have stabilised.
Climate change is undoubtedly a threat to Australia’s environment. Although Australia’s climate is so variable that the extent of change is uncertain, there is clear evidence for some warming and changes to rainfall distribution. The so-called millennium drought of the last five years was not the driest period on record in all parts of Australia, but the combination of low rainfall and warm temperatures exacerbated its effects. In the same period, rainfall over central west Australia has been higher than average. These trends are consistent with overall rainfall trends for the last 100 years.
