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Air in eThekwini

Air in 2025 (modelled): nitrogen dioxide near the ground averaged 22 µg/m³, 2.2 times WHO’s guideline of 10; winters 31 µg/m³, summers 13 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 202514 µg/m³54 µg/m³82 µmol/m²70 µmol/m²
November 202514 µg/m³57 µg/m³90 µmol/m²69 µmol/m²
October 202517 µg/m³61 µg/m³105 µmol/m²86 µmol/m²
September 202521 µg/m³59 µg/m³115 µmol/m²106 µmol/m²
August 202529 µg/m³56 µg/m³145 µmol/m²159 µmol/m²
July 202533 µg/m³45 µg/m³151 µmol/m²149 µmol/m²
June 202533 µg/m³42 µg/m³148 µmol/m²131 µmol/m²
May 202535 µg/m³50 µg/m³131 µmol/m²119 µmol/m²
April 202521 µg/m³46 µg/m³116 µmol/m²83 µmol/m²
March 202519 µg/m³52 µg/m³101 µmol/m²73 µmol/m²
February 202513 µg/m³46 µg/m³86 µmol/m²61 µmol/m²
January 202513 µg/m³49 µg/m³83 µmol/m²65 µmol/m²
December 202413 µg/m³48 µg/m³86 µmol/m²82 µmol/m²
November 202416 µg/m³62 µg/m³99 µmol/m²91 µmol/m²
October 202421 µg/m³68 µg/m³98 µmol/m²85 µmol/m²
September 202423 µg/m³66 µg/m³116 µmol/m²114 µmol/m²
August 202428 µg/m³61 µg/m³137 µmol/m²131 µmol/m²
July 202432 µg/m³46 µg/m³144 µmol/m²133 µmol/m²
June 202432 µg/m³41 µg/m³144 µmol/m²132 µmol/m²
May 202435 µg/m³48 µg/m³137 µmol/m²131 µmol/m²
April 202422 µg/m³48 µg/m³110 µmol/m²101 µmol/m²
March 202414 µg/m³46 µg/m³83 µmol/m²81 µmol/m²
February 202412 µg/m³44 µg/m³77 µmol/m²71 µmol/m²
January 202412 µg/m³43 µg/m³72 µmol/m²57 µmol/m²

Over the last five years the NO2 column averaged 145 µmol/m² in winter against 82 µmol/m² in summer, and the SO2 column 139 µmol/m² against 66 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: 14 µg/m³2004: 16 µg/m³2005: 16 µg/m³2006: 16 µg/m³2007: 16 µg/m³2008: 16 µg/m³2009: 17 µg/m³2010: 17 µg/m³2011: 16 µg/m³2012: 17 µg/m³2013: 19 µg/m³2014: 18 µg/m³2015: 18 µg/m³2016: 19 µg/m³2017: 19 µg/m³2018: 20 µg/m³2019: 21 µg/m³2020: 22 µg/m³2021: 21 µg/m³2022: 22 µg/m³2023: 22 µg/m³2024: 22 µg/m³2025: 22 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
200314 µg/m³
200416 µg/m³
200516 µg/m³
200616 µg/m³
200716 µg/m³
200816 µg/m³
200917 µg/m³
201017 µg/m³
201116 µg/m³
201217 µg/m³
201319 µg/m³
201418 µg/m³
201518 µg/m³
201619 µg/m³
201719 µg/m³
201820 µg/m³
201921 µg/m³
202022 µg/m³
202121 µg/m³
202222 µg/m³
202322 µg/m³
202422 µg/m³
202522 µg/m³

Every municipality, ranked · Everything we hold for eThekwini · 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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