This document reports on elevated particle pollution during autumn and winter 2019, using measurements from the NSW air quality monitoring network. It provides comprehensive summary on the major high particle events observed during the 2 seasons, including a catalogue of days when particle levels were over the daily benchmarks (Appendix A: Catalogue of particle events during March to August 2019).
The report finds that during autumn-winter 2019, the daily PM2.5 benchmark was exceeded on more days compared to the daily PM10 benchmark. Smoke from hazard reduction burns contributed to elevated PM2.5 during April to June, mostly in the Sydney region. Smoke from domestic wood heaters contributed to elevated PM2.5 predominantly during June to July, mainly in the Northern Tablelands region. Elevated PM10 days due to dust events mainly occurred during March and August, mostly in the South West Slopes, Hunter and Sydney regions. The report also describes trends in days over the particle benchmarks in autumn-winter seasons during the last 5 years.
This report is accompanied by 2 case studies of high pollution events during autumn-winter 2019. Case study 1: Major dust event during 5 to 6 March 2019 details the widespread dust storm which contributed to two days above the PM10 daily standard at many stations across the State. Case study 2: Smoke from Hazard Reduction Burning in the Greater Sydney Region during 20 to 25 May 2019 details another significant air pollution event for the autumn-winter 2019 period, when several days above the daily PM2.5 standard were observed in the Sydney region.