Temporal Analysis of Changes in Anthropogenic Emissions and Urban Heat Islands during COVID-19 Restrictions in Gauteng Province, South Africa
Abstract Anthropogenic emissions are significant drivers of temperature rises in major urban areas across the globe. Waste heat and exhaust emissions from motor vehicles and industrial combustion cause the warming of cities, resulting in microclimates’ changes. Recently, national lockdown regulation...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Springer
2021-05-01
|
| Series: | Aerosol and Air Quality Research |
| Subjects: | |
| Online Access: | https://doi.org/10.4209/aaqr.200437 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1823862845601742848 |
|---|---|
| author | Lerato Shikwambana Mahlatse Kganyago Paidamwoyo Mhangara |
| author_facet | Lerato Shikwambana Mahlatse Kganyago Paidamwoyo Mhangara |
| author_sort | Lerato Shikwambana |
| collection | DOAJ |
| description | Abstract Anthropogenic emissions are significant drivers of temperature rises in major urban areas across the globe. Waste heat and exhaust emissions from motor vehicles and industrial combustion cause the warming of cities, resulting in microclimates’ changes. Recently, national lockdown regulations restricting movement and socio-economic activities to curb the spread of a novel COVID-19 and the associated deaths have been implemented in various countries worldwide. Consequently, these unprecedented restrictions resulted in reductions in traffic volumes and industrial activities in most urban areas across the world. Thus, it was hypothesised that these reductions in traffic congestion and industrial activities in cities would reduce both air pollutants and thermal radiation. Using multisource data from Sentinel-5P, MERRA-2, and MODIS, this study assessed the short-term trends in emissions and land surface temperature in South Africa’s economic hub, i.e., Gauteng Province. Mann-Kendall (MK) and Sequential Mann-Kendall (SQMK) trend analysis were used to characterise trends in CO, SO2, SO4, long-wave radiation (LWR), and land surface temperature (LST) at periods corresponding to various lockdown restrictions. The results showed a significant decline in atmospheric pollutants at Level-5 lockdown restrictions, followed by an abrupt increase as the regulations were eased to Level-4 lockdown. Similarly, LST and surface urban heat island (SUHI) reduced when compared to the previous year. Therefore, the lockdown restrictions provided an experimental scenario in which pollutants could be drastically reduced, thus accentuated the human impact on microclimates. |
| format | Article |
| id | doaj-art-cde2f3edcca3441b8582d76bbcb0e63b |
| institution | Kabale University |
| issn | 1680-8584 2071-1409 |
| language | English |
| publishDate | 2021-05-01 |
| publisher | Springer |
| record_format | Article |
| series | Aerosol and Air Quality Research |
| spelling | doaj-art-cde2f3edcca3441b8582d76bbcb0e63b2025-02-09T12:21:27ZengSpringerAerosol and Air Quality Research1680-85842071-14092021-05-0121911910.4209/aaqr.200437Temporal Analysis of Changes in Anthropogenic Emissions and Urban Heat Islands during COVID-19 Restrictions in Gauteng Province, South AfricaLerato Shikwambana0Mahlatse Kganyago1Paidamwoyo Mhangara2Earth Observation directorate, South African National Space Agency, The Enterprise BuildingEarth Observation directorate, South African National Space Agency, The Enterprise BuildingSchool of Geography, Archaeology and Environmental Studies, University of the WitwatersrandAbstract Anthropogenic emissions are significant drivers of temperature rises in major urban areas across the globe. Waste heat and exhaust emissions from motor vehicles and industrial combustion cause the warming of cities, resulting in microclimates’ changes. Recently, national lockdown regulations restricting movement and socio-economic activities to curb the spread of a novel COVID-19 and the associated deaths have been implemented in various countries worldwide. Consequently, these unprecedented restrictions resulted in reductions in traffic volumes and industrial activities in most urban areas across the world. Thus, it was hypothesised that these reductions in traffic congestion and industrial activities in cities would reduce both air pollutants and thermal radiation. Using multisource data from Sentinel-5P, MERRA-2, and MODIS, this study assessed the short-term trends in emissions and land surface temperature in South Africa’s economic hub, i.e., Gauteng Province. Mann-Kendall (MK) and Sequential Mann-Kendall (SQMK) trend analysis were used to characterise trends in CO, SO2, SO4, long-wave radiation (LWR), and land surface temperature (LST) at periods corresponding to various lockdown restrictions. The results showed a significant decline in atmospheric pollutants at Level-5 lockdown restrictions, followed by an abrupt increase as the regulations were eased to Level-4 lockdown. Similarly, LST and surface urban heat island (SUHI) reduced when compared to the previous year. Therefore, the lockdown restrictions provided an experimental scenario in which pollutants could be drastically reduced, thus accentuated the human impact on microclimates.https://doi.org/10.4209/aaqr.200437LockdownCOVID-19EmissionsNitrogen dioxideSentinel-5P |
| spellingShingle | Lerato Shikwambana Mahlatse Kganyago Paidamwoyo Mhangara Temporal Analysis of Changes in Anthropogenic Emissions and Urban Heat Islands during COVID-19 Restrictions in Gauteng Province, South Africa Aerosol and Air Quality Research Lockdown COVID-19 Emissions Nitrogen dioxide Sentinel-5P |
| title | Temporal Analysis of Changes in Anthropogenic Emissions and Urban Heat Islands during COVID-19 Restrictions in Gauteng Province, South Africa |
| title_full | Temporal Analysis of Changes in Anthropogenic Emissions and Urban Heat Islands during COVID-19 Restrictions in Gauteng Province, South Africa |
| title_fullStr | Temporal Analysis of Changes in Anthropogenic Emissions and Urban Heat Islands during COVID-19 Restrictions in Gauteng Province, South Africa |
| title_full_unstemmed | Temporal Analysis of Changes in Anthropogenic Emissions and Urban Heat Islands during COVID-19 Restrictions in Gauteng Province, South Africa |
| title_short | Temporal Analysis of Changes in Anthropogenic Emissions and Urban Heat Islands during COVID-19 Restrictions in Gauteng Province, South Africa |
| title_sort | temporal analysis of changes in anthropogenic emissions and urban heat islands during covid 19 restrictions in gauteng province south africa |
| topic | Lockdown COVID-19 Emissions Nitrogen dioxide Sentinel-5P |
| url | https://doi.org/10.4209/aaqr.200437 |
| work_keys_str_mv | AT leratoshikwambana temporalanalysisofchangesinanthropogenicemissionsandurbanheatislandsduringcovid19restrictionsingautengprovincesouthafrica AT mahlatsekganyago temporalanalysisofchangesinanthropogenicemissionsandurbanheatislandsduringcovid19restrictionsingautengprovincesouthafrica AT paidamwoyomhangara temporalanalysisofchangesinanthropogenicemissionsandurbanheatislandsduringcovid19restrictionsingautengprovincesouthafrica |