Subtle Changes or Dramatic Perceptions of Air Pollution in Sydney during COVID-19
The COVID-19 pandemic made it critical to limit the spread of the disease by enforcing human isolation, restricting travel and reducing social activities. Dramatic improvements to air quality, especially NO<sub>2</sub>, have often characterised places under COVID-19 restrictions. Air pol...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-01-01
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| Series: | Environments |
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| Online Access: | https://www.mdpi.com/2076-3298/8/1/2 |
| _version_ | 1797542595781459968 |
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| author | Peter Brimblecombe Yonghang Lai |
| author_facet | Peter Brimblecombe Yonghang Lai |
| author_sort | Peter Brimblecombe |
| collection | DOAJ |
| description | The COVID-19 pandemic made it critical to limit the spread of the disease by enforcing human isolation, restricting travel and reducing social activities. Dramatic improvements to air quality, especially NO<sub>2</sub>, have often characterised places under COVID-19 restrictions. Air pollution measurements in Sydney in April 2019 and during the lockdown period in April 2020 show reduced daily averaged NO<sub>2</sub> concentrations: 8.52 ± 1.92 and 7.85 ± 2.92 ppb, though not significantly so (<i>p</i><sub>1</sub>~0.15) and PM<sub>2.5</sub> 8.91 ± 4.94 and 7.95 ± 2.64 µg m<sup>−3</sup>, again a non-significant difference (<i>p</i><sub>1</sub>~0.18). Satellite imagery suggests changes that parallel those at ground level, but the column densities averaged over space and time, in false-colour, are more dramatic. Changed human mobility could be traced in increasing times spent at home, assessed from <i>Google Mobility Reports</i> and mirrored in decreased traffic flow on a major road, suggesting compliance with the restrictions. Electricity demand for the State of New South Wales was low under lockdown in early April 2020, but it recovered rapidly. Analysis of the uses of search terms: bushfires, air quality, haze and air pollution using <i>Google Trends</i> showed strong links between bushfires and pollution-related terms. The smoke from bushfires in late 2019 may well have added to the general impression of improved air quality during lockdown, despite only modest changes in the ground level measurements. This gives hints that successful regulation of air quality requires maintaining a delicate balance between our social perceptions and the physical reality. |
| first_indexed | 2024-03-10T13:32:48Z |
| format | Article |
| id | doaj.art-4af1b6d9f9674a22bab03146ca9f89c9 |
| institution | Directory Open Access Journal |
| issn | 2076-3298 |
| language | English |
| last_indexed | 2024-03-10T13:32:48Z |
| publishDate | 2021-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Environments |
| spelling | doaj.art-4af1b6d9f9674a22bab03146ca9f89c92023-11-21T07:43:47ZengMDPI AGEnvironments2076-32982021-01-0181210.3390/environments8010002Subtle Changes or Dramatic Perceptions of Air Pollution in Sydney during COVID-19Peter Brimblecombe0Yonghang Lai1Department of Marine Environment and Engineering, National Sun Yat-Sen University, Kaohsiung 80424, TaiwanSchool of Energy and Environment, City University of Hong Kong, Hong Kong, ChinaThe COVID-19 pandemic made it critical to limit the spread of the disease by enforcing human isolation, restricting travel and reducing social activities. Dramatic improvements to air quality, especially NO<sub>2</sub>, have often characterised places under COVID-19 restrictions. Air pollution measurements in Sydney in April 2019 and during the lockdown period in April 2020 show reduced daily averaged NO<sub>2</sub> concentrations: 8.52 ± 1.92 and 7.85 ± 2.92 ppb, though not significantly so (<i>p</i><sub>1</sub>~0.15) and PM<sub>2.5</sub> 8.91 ± 4.94 and 7.95 ± 2.64 µg m<sup>−3</sup>, again a non-significant difference (<i>p</i><sub>1</sub>~0.18). Satellite imagery suggests changes that parallel those at ground level, but the column densities averaged over space and time, in false-colour, are more dramatic. Changed human mobility could be traced in increasing times spent at home, assessed from <i>Google Mobility Reports</i> and mirrored in decreased traffic flow on a major road, suggesting compliance with the restrictions. Electricity demand for the State of New South Wales was low under lockdown in early April 2020, but it recovered rapidly. Analysis of the uses of search terms: bushfires, air quality, haze and air pollution using <i>Google Trends</i> showed strong links between bushfires and pollution-related terms. The smoke from bushfires in late 2019 may well have added to the general impression of improved air quality during lockdown, despite only modest changes in the ground level measurements. This gives hints that successful regulation of air quality requires maintaining a delicate balance between our social perceptions and the physical reality.https://www.mdpi.com/2076-3298/8/1/2Australiabushfireslockdownpublic perceptionsocial mediatraffic |
| spellingShingle | Peter Brimblecombe Yonghang Lai Subtle Changes or Dramatic Perceptions of Air Pollution in Sydney during COVID-19 Environments Australia bushfires lockdown public perception social media traffic |
| title | Subtle Changes or Dramatic Perceptions of Air Pollution in Sydney during COVID-19 |
| title_full | Subtle Changes or Dramatic Perceptions of Air Pollution in Sydney during COVID-19 |
| title_fullStr | Subtle Changes or Dramatic Perceptions of Air Pollution in Sydney during COVID-19 |
| title_full_unstemmed | Subtle Changes or Dramatic Perceptions of Air Pollution in Sydney during COVID-19 |
| title_short | Subtle Changes or Dramatic Perceptions of Air Pollution in Sydney during COVID-19 |
| title_sort | subtle changes or dramatic perceptions of air pollution in sydney during covid 19 |
| topic | Australia bushfires lockdown public perception social media traffic |
| url | https://www.mdpi.com/2076-3298/8/1/2 |
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