Issues

• Values: what do we need to sustain?
• Constraints
• SoE and Limits to Knowledge

• Atmosphere
• Land
• Inland Waters and Wetlands
• Biodiversity
• Settlements
• Cultural Heritage
• Coastal, Estuarine and Marine

• Response Instruments
• Summary of Report Recommendations
• Strategic Recommendations
• Conclusion

This sustainability review of the Atmosphere Chapter summarises the chapter content and provides an overview from a 'sustainability' perspective. A similar framework is used for all chapters within the 'Sustainability Review'. This provides a consistent way of comparing the major findings across the SoE Report within this final chapter. The 'Sustainability Review' provides the highest-level summary of each of the chapters. More detailed information is provided within each of the major theme chapters. Links are provided to the issue reports referred to in the 'conditions and trends' section below.

The content is organised under five major headings from a higher-level summary in the section entitled 'objective' to comparatively more detail in the section on 'conditions and trends' and 'what has been achieved'.

1. Objective: Presents an objective for air quality in Tasmania.
    
2. Integrating concepts or indicators: Reports on any integrating concepts or indicators provided in the chapter.
    
3. Capacity to assess and measure: Reports on capacity to assess conditions and trends for this chapter theme.
    
4. Conditions and trends: Presents a summary of the key findings of the chapter, with links back to the related Issue Reports for further detail.
    
5. What has been achieved, 1998-2003: Presents a summary of key initiatives over the five year review period for the Second SoE Report.
    

Air quality objective

This objective reflects the vision established by Tasmania Together and the key findings of the Atmosphere Chapter. Applicable Tasmania Together goals and standards include: 'To reduce air and water pollution' (Goal 24); and 'To mitigate the effects of greenhouse gases and ozone-depleting substances and where possible, reduce their emissions' (Goal 24) (see also Tasmania Together Goals applicable to the Atmosphere Chapter).

Reducing total exposure to air pollution from indoor and ambient sources through: enhanced monitoring capacity and networks for a wider range of pollutants; improved understanding of meteorological conditions that exacerbate air quality problems; improved understanding of indoor air quality issues; implementation of best-practice emission control; and, continuous improvement programs to reduce emissions of airborne contaminants.

Integrating concepts or indicators

The best available overview measure for air quality in Tasmania is particulate pollution as it is recognised as the major air quality issue for Tasmania. The concentration of particles is used as an indicator of urban ambient air quality. Smoke emissions from wood heaters are considered the primary source of particulate pollution, although other less well-documented sources include transportation, industrial and burning/wildfire sources. Large and small particles transported through the air can affect human health, cause damage to property and contaminate soil and water. As indicated above, there has been a significant improvement in the air quality of Launceston since the last SoE Report. However, little is known at present about population centres other than Hobart and Launceston, or about PM_2.5. Indicators included in the Issue Report are: Exceedences of NEPM Air Quality Standards for Particulate Concentrations and Emission of Air Pollutants. The latter is based on National Pollutant Inventory (NPI) data.

Capacity to assess and measure

Information used in the chapter relies on sources including: specific local research on indoor air quality; national and global monitoring networks; and State Government monitoring of ambient air quality by the Department of Primary Industries, Water and Environment. The trace gas data from the Cape Grim Baseline Air Pollution Station are provided courtesy of CSIRO Atmospheric Research. The Cape Grim Station is operated by the Bureau of Meteorology, and its scientific program managed jointly with CSIRO Atmospheric Research. Overall, there has been an improvement in capacity to report on air quality conditions and trends in Tasmania.

Conditions and trends

The Atmosphere Chapter reviews conditions and trends under three broad topics: variability and change; ambient air quality; and indoor air quality.

Climate Variability: The seasonal graphs for 13 Bureau of Meteorology sites hint at the complex changes that have occurred in the rainfall distribution. For example, the sites such as Sorell, Swan Island and Ormley have seen relatively high summer rainfall and relatively low winter rainfall over the last 10 to 20 years, but at Queenstown the reverse is true, at least for some of the period.

Enhanced Greenhouse Effect: There are significant variations through time of the average height of the sea that make the identification of long-term trends in sea level very difficult. Data series of many decades is probably necessary to properly identify long-term trends in sea-level. Current estimates of global sea-level rise due to the enhanced greenhouse effect are about 1 to 2 mm per year (Church et al. 2001). Robust estimates of such trends will require observations over several decades. Fort Denison in Sydney and Fremantle are viewed as important sites in global evaluations of sea-level (Lambert 2002). The average corrected sea-level rise is 1.4 mm/year from these sites (Lambert 2002 and Mitchell et al. 2001). In Hobart, the trend has been 0.62 mm/year (Mitchell et al. 2001), although the total duration of this data was less than 40 years, which is generally considered inadequate for deriving an estimate of long-term sea level change. The Port Arthur baseline, set in 1841, provides an important benchmarks for sea-level changes in Australia, and for the southern hemisphere as a whole. Analysis indicates that there has been a relative rise in sea-level of about 13 cm in the area since 1841. Once adjusted for vertical movements of the land, the rate of change is between 0.8 and 1 mm/year. Global predictions are for the rate of change to increase, such that by 2100 sea level will be between 9 and 88 cm above the 1990 global average sea-level.

Ozone Depletion: Concentrations of most ozone-depleting substances in the stratosphere are declining. Nevertheless, Tasmania will experience minimum ozone levels for the next 10 to 15 years. Although the ozone hole was greatly reduced in 2002, there is no conclusive evidence of long-term ozone recovery. Indications are that the 2003 ozone hole will be larger due to colder atmospheric conditions. Collection of CFC and HCFC data for Tasmania is lacking.

Meteorological Conditions: Temperature inversions are the most common meteorological condition that can exacerbate air quality problems by trapping pollutants near the ground, and these occur regularly in Tasmania with the amount of fog often indicating the severity.

Particulate Pollution: Between 1997 and 2002, the annual average PM₁₀ concentration, measured at Ti Tree Bend in Launceston, has decreased from 34 to 19 µg/m³ (a 44% reduction). While there are still exceedences of the Air Quality National Environment Protection Measure (NEPM), the number of days exceeding the 24-hour standard has reduced from 51 to 14. There has been a marked improvement in the severity of poor air quality incidents, and the target of no more than five exceedences a year is much closer to being achieved. Preliminary results for 2003 suggest that there were 23 exceedences of the Air NEPM standard, reflecting the colder and wetter winter in comparison with recent years, and the 5 exceedences associated with either bushfires or planned burns. It is acknowledged that air quality in Hobart may vary due to changes in topography and micro-climate and there is some preliminary evidence to suggest that some parts of Hobart have poorer air quality than that recorded at the Prince of Wales Bay monitoring station. Little is known at present about population centres other than Hobart and Launceston, or about smaller particle concentrations.

Air Toxics: There are few data on the magnitude and location of any potential air toxics issues for Tasmania. Some information is available from the National Pollutant Inventory. It is likely that some limited measurements will be made in Launceston during 2004.

Carbon Monoxide: Historical data for Hobart suggests that there was a significant improvement of carbon monoxide concentration during the mid-1980s. A two month study in 1991 suggested that levels had gone up again. Current monitoring in Hobart has not shown any exceedences of the NEPM standard, however these measurements are aimed at characterising carbon monoxide concentrations from woodsmoke sources rather than from motor vehicles within the Hobart CBD as in the previous studies. Improvements in monitoring should allow conditions and trends to be reported in the future.

Transport Emissions: There has been virtually no direct monitoring of transport emissions in Tasmania. However, there is anecdotal information that the State's vehicle fleet is not likely to compare well to other jurisdictions in the areas of fuel efficiency and vehicle maintenance.

Commercial and Residential Indoor Air Quality: In 1997, the Australian Bureau of Statistics estimated that less than 4% of time was spent outdoors. Many common indoor air pollutants have also been shown to cause adverse health effects even at low concentrations. However, there is no trend information available on indoor air quality.

What has been achieved, 1998-2003

The following are some of the key initiatives in relation to atmosphere and air quality. Further information is provided in the Atmosphere Chapter.

• The development of the draft EPP for Air Quality 2001 and the Air Quality Monitoring Plan.
   
• The education and wood heater replacement program is a key initiative to address particulate pollution in Launceston. By September 2003 this program had resulted in 1,500 wood heater replacements and distribution of 700 cards warning of excessively smoky chimneys.
   
• Banning of smoking in many public places
   
• Improved reporting and regulation of industrial air emissions.
   
• The 1999 Tasmanian Greenhouse Statement highlights a number of areas where Tasmania can assist Australia meet the requirements of the Kyoto Protocol.
   
• A program has been in place in Australia to collect and destroy the halons in use around the country. The Halon Bank has taken over 1.3 thousand tonnes of Halon-1211, and over 600 tonnes of Halon-1301 since 1993. Tasmania contributed to 4% and 5% of these totals respectively.