Impact of the 2019/2020 Australian Megafires on Air Quality and Health

Ailish M Graham; Kirsty J Pringle; Richard J Pope; Stephen R Arnold; Luke A Conibear; Helen Burns; Richard Rigby; Nicolás Borchers-Arriagada; Edward W Butt; Laura Kiely; Carly Reddington; Dominick V Spracklen; Matthew T Woodhouse; Christoph Knote; James B McQuaid

doi:10.1029/2021GH000454

Impact of the 2019/2020 Australian Megafires on Air Quality and Health

Geohealth. 2021 Oct 1;5(10):e2021GH000454. doi: 10.1029/2021GH000454. eCollection 2021 Oct.

Authors

Ailish M Graham¹, Kirsty J Pringle¹, Richard J Pope^{1

2}, Stephen R Arnold¹, Luke A Conibear¹, Helen Burns^{1

3}, Richard Rigby^{1

3}, Nicolás Borchers-Arriagada⁴, Edward W Butt¹, Laura Kiely¹, Carly Reddington¹, Dominick V Spracklen¹, Matthew T Woodhouse⁵, Christoph Knote⁶, James B McQuaid¹

Affiliations

¹ School of Earth and Environment University of Leeds Leeds UK.
² National Centre for Earth Observation University of Leeds Leeds UK.
³ Centre for Environmental Modelling and Computation University of Leeds Leeds UK.
⁴ Menzies Institute for Medical Research University of Tasmania Hobart TAS Australia.
⁵ Commonwealth Scientific and Industrial Research Organisation Aspendale VIC Australia.
⁶ Model-Based Environmental Exposure Science, Faculty of Medicine University of Augsburg Germany Augsburg Germany.

Abstract

The Australian 2019/2020 bushfires were unprecedented in their extent and intensity, causing a catastrophic loss of habitat, human and animal life across eastern-Australia. We use a regional air quality model to assess the impact of the bushfires on particulate matter with a diameter less than 2.5 μm (PM_2.5) concentrations and the associated health impact from short-term population exposure to bushfire PM_2.5. The mean population Air Quality Index (AQI) exposure between September and February in the fires and no fires simulations indicates an additional ∼437,000 people were exposed to "Poor" or worse AQI levels due to the fires. The AQ impact was concentrated in the cities of Sydney, Newcastle-Maitland, Canberra-Queanbeyan and Melbourne. Between October and February 171 (95% CI: 66-291) deaths were brought forward due to short-term exposure to bushfire PM_2.5. The health burden was largest in New South Wales (NSW) (109 (95% CI: 41-176) deaths brought forward), Queensland (15 (95% CI: 5-24)), and Victoria (35 (95% CI: 13-56)). This represents 38%, 13% and 30% of the total deaths brought forward by short-term exposure to all PM_2.5. At a city-level 65 (95% CI: 24-105), 23 (95% CI: 9-38) and 9 (95% CI: 4-14) deaths were brought forward from short-term exposure to bushfire PM_2.5, accounting for 36%, 20%, and 64% of the total deaths brought forward from all PM_2.5. Thus, the bushfires caused substantial AQ and health impacts across eastern-Australia. Climate change is projected to increase bushfire risk, therefore future fire management policies should consider this.

Keywords: Australia; PM2.5; air quality; bushfire; health impact assessment; wildfire.