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Air in Gert Sibande

Air in 2025 (modelled): nitrogen dioxide near the ground averaged 25 µg/m³, 2.5 times WHO’s guideline of 10; winters 32 µg/m³, summers 16 µg/m³.

Nitrogen dioxide (NO2) comes mostly from burning: power stations, vehicles, industry. Near the ground is what people breathe. The column is all of it in the air above, from the ground to the top of the sky, which is what a satellite sees. Sulphur dioxide (SO2) comes mostly from burning coal. Ozone forms in sunlight from other pollutants.

Modelled, not measured: these figures come from the Copernicus Atmosphere Monitoring Service’s reanalysis, a weather and chemistry model that takes in satellite readings. Its cells are about 80 km across, so a busy road or a smoky winter evening in one suburb is smoothed into the region around it. It is not a reading at any address.

2025

WHO’s 2021 guideline for nitrogen dioxide is 10 µg/m³ as a yearly mean. It is a long-term health guideline, not a legal limit (South Africa’s national standard for the yearly mean is set separately), and these are modelled regional means, not readings where you live.

Month by month

MonthNO2 near the groundOzone near the groundNO2 columnSO2 column
December 202519 µg/m³48 µg/m³110 µmol/m²163 µmol/m²
November 202519 µg/m³47 µg/m³131 µmol/m²172 µmol/m²
October 202524 µg/m³52 µg/m³152 µmol/m²214 µmol/m²
September 202524 µg/m³50 µg/m³156 µmol/m²243 µmol/m²
August 202535 µg/m³41 µg/m³208 µmol/m²297 µmol/m²
July 202535 µg/m³32 µg/m³233 µmol/m²321 µmol/m²
June 202533 µg/m³30 µg/m³217 µmol/m²267 µmol/m²
May 202531 µg/m³30 µg/m³219 µmol/m²270 µmol/m²
April 202525 µg/m³31 µg/m³162 µmol/m²198 µmol/m²
March 202520 µg/m³39 µg/m³124 µmol/m²169 µmol/m²
February 202514 µg/m³39 µg/m³97 µmol/m²134 µmol/m²
January 202516 µg/m³41 µg/m³99 µmol/m²127 µmol/m²
December 202418 µg/m³49 µg/m³119 µmol/m²181 µmol/m²
November 202423 µg/m³54 µg/m³133 µmol/m²189 µmol/m²
October 202420 µg/m³62 µg/m³136 µmol/m²209 µmol/m²
September 202424 µg/m³53 µg/m³151 µmol/m²213 µmol/m²
August 202432 µg/m³44 µg/m³212 µmol/m²286 µmol/m²
July 202436 µg/m³32 µg/m³231 µmol/m²270 µmol/m²
June 202432 µg/m³32 µg/m³192 µmol/m²229 µmol/m²
May 202433 µg/m³33 µg/m³195 µmol/m²275 µmol/m²
April 202422 µg/m³33 µg/m³156 µmol/m²208 µmol/m²
March 202418 µg/m³39 µg/m³117 µmol/m²176 µmol/m²
February 202418 µg/m³43 µg/m³106 µmol/m²170 µmol/m²
January 202418 µg/m³46 µg/m³91 µmol/m²145 µmol/m²

Over the last five years the NO2 column averaged 212 µmol/m² in winter against 106 µmol/m² in summer, and the SO2 column 274 µmol/m² against 150 µmol/m²: still winter air holds what is burnt close to the ground, and more is burnt to keep warm.

Every year since 2003

2003: 19 µg/m³2004: 19 µg/m³2005: 20 µg/m³2006: 20 µg/m³2007: 20 µg/m³2008: 21 µg/m³2009: 21 µg/m³2010: 22 µg/m³2011: 21 µg/m³2012: 22 µg/m³2013: 21 µg/m³2014: 22 µg/m³2015: 22 µg/m³2016: 22 µg/m³2017: 22 µg/m³2018: 22 µg/m³2019: 23 µg/m³2020: 22 µg/m³2021: 22 µg/m³2022: 24 µg/m³2023: 24 µg/m³2024: 25 µg/m³2025: 25 µg/m³200320082013201820232025
Nitrogen dioxide near the ground, each year’s mean (modelled). The line is WHO’s yearly guideline, 10 µg/m³.
Show the numbers
Nitrogen dioxide near the ground, the mean of each year, 2003 to 2025: every figure
When or whatFigure
200319 µg/m³
200419 µg/m³
200520 µg/m³
200620 µg/m³
200720 µg/m³
200821 µg/m³
200921 µg/m³
201022 µg/m³
201121 µg/m³
201222 µg/m³
201321 µg/m³
201422 µg/m³
201522 µg/m³
201622 µg/m³
201722 µg/m³
201822 µg/m³
201923 µg/m³
202022 µg/m³
202122 µg/m³
202224 µg/m³
202324 µg/m³
202425 µg/m³
202525 µg/m³

Every municipality, ranked · Everything we hold for Gert Sibande · On the explore map

Source

Modelled, not measured: these figures come from the Copernicus Atmosphere Monitoring Service’s reanalysis, a weather and chemistry model that takes in satellite readings. Its cells are about 80 km across, so a busy road or a smoky winter evening in one suburb is smoothed into the region around it. It is not a reading at any address.

How we worked this out

What we changed: we averaged the reanalysis’s monthly means over each place by its area in each 0.75 degree cell, turned NO2 and ozone on the model’s lowest level from mass mixing ratio into micrograms per m3 with the month’s air density (surface pressure and temperature), and the columns from kg per m2 into micromol per m2.

Particles (PM2.5, PM10) and sulphur dioxide near the ground are not shown yet: the model reads them far higher over Gauteng and the Highveld than is plausible for a regional mean, so they wait for a check against ground stations.

Contains modified Copernicus Atmosphere Monitoring Service information 2003 to 2025. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains. Copernicus Atmosphere Monitoring Service (2020): CAMS global reanalysis (EAC4) monthly averaged fields. Copernicus Atmosphere Monitoring Service (CAMS) Atmosphere Data Store, DOI 10.24381/fd75fff2. Inness, A. and others (2019): The CAMS reanalysis of atmospheric composition, Atmos. Chem. Phys., 19, 3515 to 3556. Under CC BY 4.0.

Dataset: air quality by municipality, release of 12 November 2026.

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