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Air in Moqhaka

Air in 2025 (modelled): nitrogen dioxide near the ground averaged 15 µg/m³, 1.5 times WHO’s guideline of 10; winters 20 µg/m³, summers 11 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 202512 µg/m³57 µg/m³71 µmol/m²75 µmol/m²
November 202511 µg/m³56 µg/m³73 µmol/m²65 µmol/m²
October 202513 µg/m³63 µg/m³86 µmol/m²77 µmol/m²
September 202514 µg/m³62 µg/m³91 µmol/m²98 µmol/m²
August 202520 µg/m³52 µg/m³102 µmol/m²99 µmol/m²
July 202521 µg/m³42 µg/m³107 µmol/m²107 µmol/m²
June 202519 µg/m³41 µg/m³117 µmol/m²97 µmol/m²
May 202520 µg/m³41 µg/m³115 µmol/m²103 µmol/m²
April 202517 µg/m³40 µg/m³86 µmol/m²66 µmol/m²
March 202516 µg/m³51 µg/m³84 µmol/m²77 µmol/m²
February 202512 µg/m³54 µg/m³97 µmol/m²101 µmol/m²
January 202512 µg/m³59 µg/m³84 µmol/m²94 µmol/m²
December 20248.6 µg/m³60 µg/m³67 µmol/m²74 µmol/m²
November 202411 µg/m³63 µg/m³75 µmol/m²73 µmol/m²
October 202414 µg/m³70 µg/m³92 µmol/m²112 µmol/m²
September 202413 µg/m³63 µg/m³87 µmol/m²96 µmol/m²
August 202416 µg/m³54 µg/m³86 µmol/m²79 µmol/m²
July 202420 µg/m³41 µg/m³92 µmol/m²59 µmol/m²
June 202423 µg/m³39 µg/m³146 µmol/m²140 µmol/m²
May 202427 µg/m³43 µg/m³108 µmol/m²108 µmol/m²
April 202417 µg/m³44 µg/m³94 µmol/m²94 µmol/m²
March 202415 µg/m³55 µg/m³101 µmol/m²112 µmol/m²
February 202412 µg/m³52 µg/m³75 µmol/m²83 µmol/m²
January 20249.9 µg/m³56 µg/m³60 µmol/m²71 µmol/m²

Over the last five years the NO2 column averaged 113 µmol/m² in winter against 78 µmol/m² in summer, and the SO2 column 103 µmol/m² against 82 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: 11 µg/m³2004: 10 µg/m³2005: 11 µg/m³2006: 11 µg/m³2007: 11 µg/m³2008: 12 µg/m³2009: 12 µg/m³2010: 12 µg/m³2011: 12 µg/m³2012: 12 µg/m³2013: 13 µg/m³2014: 13 µg/m³2015: 14 µg/m³2016: 13 µg/m³2017: 14 µg/m³2018: 15 µg/m³2019: 16 µg/m³2020: 15 µg/m³2021: 15 µg/m³2022: 15 µg/m³2023: 15 µg/m³2024: 16 µg/m³2025: 15 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
200311 µg/m³
200410 µg/m³
200511 µg/m³
200611 µg/m³
200711 µg/m³
200812 µg/m³
200912 µg/m³
201012 µg/m³
201112 µg/m³
201212 µg/m³
201313 µg/m³
201413 µg/m³
201514 µg/m³
201613 µg/m³
201714 µg/m³
201815 µg/m³
201916 µg/m³
202015 µg/m³
202115 µg/m³
202215 µg/m³
202315 µg/m³
202416 µg/m³
202515 µg/m³

See it in the Copernicus Browser, the European Space Agency’s free viewer, on the newest image: Sentinel-5P, nitrogen dioxide · Sentinel-5P, sulphur dioxide. These are Sentinel-5P’s observed columns for one day, not our modelled yearly figures; days with cloud have gaps.

Every municipality, ranked · Everything we hold for Moqhaka · 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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