4613.0 - Australia's Environment: Issues and Trends, 2006
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 10/11/2006
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AIR QUALITY PARTICULATE CONCENTRATIONS, DAILY 24-HOUR PM2.5 Source: State environmental protection agencies, 2006. PARTICULATE CONCENTRATIONS, DAILY 24-HOUR PM10, SELECTED CITIES Particles may be solid matter or liquid droplets. PM10 (particles of 10 micrometres in diameter) and smaller particles are small enough to penetrate deeply into the lungs. Particles can aggravate existing respiratory and cardiovascular disease. Particles are emitted from industrial processes, motor vehicles, domestic fuel burning and industrial and domestic incineration. Particles result from all sorts of combustion including bushfires and volcanoes. The current one-day standard for PM10 is 50 µg/m3 (micrograms per cubic metre) with a maximum allowable exceedence of five days a year. Overall, air quality in Australia is relatively good. Traditionally many cities, such as Canberra, have PM10 exceedences due to emissions from domestic wood heaters. Between 1997 and 2001, the level of exceedence for fine particle health standards in selected urban areas on average was acceptable. There was a rise in 2002 and 2003, mainly due to severe forest fires and dust storms around the Sydney, Canberra and Melbourne areas which caused the National Environment Protection Measure (NEPM) goal to be exceeded on 13 days in Sydney in 2002, 13 days in Canberra in 2003 and 10 days in Melbourne in 2003. It was also exceeded on eight days in Brisbane in 2002. PARTICULATE CONCENTRATIONS, DAILY 24-HOUR PM10, SELECTED CITIES Source: State environmental protection agencies, 2006. DAILY PEAK 4-HOUR OZONE (PHOTOCHEMICAL SMOG) Ozone or photochemical smog is a problem in most large cities. It is caused by emissions from industry, motor vehicles, domestic wood combustion and other sources, accumulating under certain meteorological conditions. Ozone is produced photochemically in air by reactions between hydrocarbons and nitrogen oxides. Some hours of strong sunlight are required to allow high levels of oxidant to form. Light wind conditions are also required to minimise its dispersion. Ozone affects the linings of the throat and lungs, restricting the air passages and making breathing difficult. It also increases the risk of respiratory infections and eye irritation. The current four-hour standard level for oxidant is 0.08 parts per million (ppm). The maximum allowable exceedence should be one day a year. Ozone has been monitored in most cities since the late 1970s. Ozone levels have declined significantly over that period although in recent years the trends are not as apparent. There is significant year-to-year variability in peak ozone levels due to weather variability. In Sydney, exceedences are partly due to the topography of the Sydney Basin. DAILY PEAK 4-HOUR OZONE (PHOTOCHEMICAL SMOG) Source: State environmental protection agencies, 2006. SULPHUR DIOXIDE, DAYS OF EXCEEDENCE, SELECTED REGIONAL CENTRES Sulphur dioxide (SO2) is a colourless, irritating and reactive gas with a strong odour. In Australia, emissions of sulphur dioxide are primarily from industrial operations that burn fuels such as coal, oil, petroleum and gas and from wood pulping and paper manufacturing. It is also emitted by vehicles. It irritates the eyes, nose and throat, and people with impaired lungs or hearts and asthmatics are particularly at risk of exacerbating existing health problems. Ambient SO2 concentrations are generally low. Levels of SO2 vary between regions due to varied geographical distribution of major sources and different topographical and meteorological conditions. Sulphur dioxide levels in Australian cities are low compared to the USA and Europe because of the limited number of major SO2 emitting industries and low sulphur fuels. Sulphur dioxide pollution has been an issue in some mining areas, but is generally improving. Due to improvements in mineral extraction and processing activities at Kalgoorlie in Western Australia, SO2 levels have been reduced dramatically over the last 12 years. In the Illawarra district of New South Wales the copper smelting operations at Port Kembla have recently ceased and SO2 levels are expected to reduce. In recent years, one hour SO2 levels have been below the National Environment Protection Measure (NEPM) standard levels at Gladstone, the Lower Hunter and La Trobe Valley (power generation areas using coal), however levels remain high at Port Pirie and Mt Isa. SULPHUR DIOXIDE, DAYS OF EXCEEDENCE, SELECTED REGIONAL CENTRES Note: The National Environment Protection Measure guideline for SO2 concentrations of 0.2 parts per million is maximum allowable exceedences should be one day a year for one hour standard limit of sulphur dioxide. Source: State environmental protection agencies, 2006. MOTOR VEHICLE USAGE, MILLION VEHICLE KILOMETRES The pollutants emitted by road transport contribute greatly to poor air quality that damages human and ecosystem health. Motor vehicle emissions also contain carbon monoxide and other greenhouse gases (GHGs). Changes in the volume of road traffic impact on GHG emissions and concentrations of atmospheric pollutants. There has been less and less lead in Australia's air since the introduction of unleaded petrol in 1986 and the eventual phase out of leaded petrol nationally by 1 January 2002. Australians drive an estimated 206 billion kilometres (km) each year. The amount of vehicle kilometres travelled has increased by 8.5% between 2001 and 2005. Cars account for about three-quarters of all road traffic. In 2005, Australia's eleven million registered passenger vehicles travelled an estimated 155 billion km, each averaging 14,100 km per year. Just over 421,500 motor cycles travelled 1.5 billion km, while the fleet of just over 62,000 buses travelled 1.9 billion km (ABS cat. no. 9208.0). Motor vehicles in total travelled an estimated total distance of 206,383 million km in 2005, at an average of 14,800 km per vehicle. Business use accounted for about one-third of aggregate distance travelled, and private use for two-thirds (67%). Of total private use travel, 35% consisted of travel to and from work, and 65% for personal and other use travel (ABS cat. no. 9208.0). Personal travel occurs for many reasons, including school, business, recreation and travel to and from work. While road transport accounts for the majority of domestic passenger trips undertaken, rail services are used by a considerable number of urban commuters. Air services provide for a large proportion of long distance passenger travel. Only 5% of total distance travelled represented interstate trips, while 53% of trips were within the capital city of the state or territory in which the vehicle was registered (ABS cat. no. 9208.0). There have been positive changes in vehicle design and fuel standards, resulting in a reduction of ambient air concentration of CO (carbon monoxide) in high traffic areas throughout the major cities of Australia.
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