A Clean Air Plan for Sydney: An Overview of the Special Issue on Air Quality in New South Wales

Abstract

This paper presents a summary of the key findings of the special issue of Atmosphere on Air Quality in New South Wales and discusses the implications of the work for policy makers and individuals. This special edition presents new air quality research in Australia undertaken by (or in association with) the Clean Air and Urban Landscapes hub, which is funded by the National Environmental Science Program on behalf of the Australian Government’s Department of the Environment and Energy. Air pollution in Australian cities is generally low, with typical concentrations of key pollutants at much lower levels than experienced in comparable cities in many other parts of the world. Australian cities do experience occasional exceedances in ozone and PM2.5 (above air pollution guidelines), as well as extreme pollution events, often as a result of bushfires, dust storms, or heatwaves. Even in the absence of extreme events, natural emissions play a significant role in influencing the Australian urban environment, due to the remoteness from large regional anthropogenic emission sources. By studying air quality in Australia, we can gain a greater understanding of the underlying atmospheric chemistry and health risks in less polluted atmospheric environments, and the health benefits of continued reduction in air pollution. These conditions may be representative of future air quality scenarios for parts of the Northern Hemisphere, as legislation and cleaner technologies reduce anthropogenic air pollution in European, American, and Asian cities. However, in many instances, current legislation regarding emissions in Australia is significantly more lax than in other developed countries, making Australia vulnerable to worsening air pollution in association with future population growth. The need to avoid complacency is highlighted by recent epidemiological research, reporting associations between air pollution and adverse health outcomes even at air pollutant concentrations that are lower than Australia’s national air quality standards. Improving air quality is expected to improve health outcomes at any pollution level, with specific benefits projected for reductions in long-term exposure to average PM2.5 concentrations.

Temperature response measurements from eucalypts give insight into the impact of Australian isoprene emissions on air quality in 2050

“…Rather, their emissions must be accommodated via atmospheric NO X reductions. However new urban developments should consider the BVOC emission potential of prospective trees before planting (Paton-Walsh et al, 2019).…”

Temperature response measurements from eucalypts give insight into the impact of Australian isoprene emissions on air quality in 2050

“…Leaf temperature was controlled using the Walz cuvette and was programmed to increase leaf temperature in 5 K steps from 293 to 328 K in 7 min intervals to accommodate adjustment to new steadystate values of photosynthesis at each temperature. This time corresponds to the duration of intermediate-length sunflecks in plant canopies (Pearcy, 1990) and also results in a common, standardised heat dose for all the leaves (Niinemets and Sun, 2015). Basal emission rates are taken as the emission rate measured at 1000 µmol m −2 s −1 PAR and 303 K.…”

Effective reduction of roadside air pollution with botanical biofiltration

“…Emissions from motor vehicles are a major source of air pollution in Sydney (NSW Health 2014;Paton-Walsh et al 2019) and are the largest contributors of NOx (Cowie et al 2019) and PM2.5 pollution (Crawford et al 2017). Motor vehicles also emit VOCs, which are important precursors in the formation of ozone (NSW Health 2014).…”