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Air in Richmond

Air in 2025 (modelled): nitrogen dioxide near the ground averaged 16 µg/m³, 1.6 times WHO’s guideline of 10; winters 23 µg/m³, summers 10 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 20259.8 µg/m³51 µg/m³64 µmol/m²53 µmol/m²
November 202511 µg/m³51 µg/m³77 µmol/m²53 µmol/m²
October 202512 µg/m³59 µg/m³87 µmol/m²63 µmol/m²
September 202515 µg/m³58 µg/m³96 µmol/m²79 µmol/m²
August 202521 µg/m³51 µg/m³108 µmol/m²116 µmol/m²
July 202524 µg/m³39 µg/m³110 µmol/m²104 µmol/m²
June 202523 µg/m³38 µg/m³115 µmol/m²97 µmol/m²
May 202523 µg/m³43 µg/m³94 µmol/m²87 µmol/m²
April 202516 µg/m³39 µg/m³91 µmol/m²59 µmol/m²
March 202514 µg/m³49 µg/m³78 µmol/m²52 µmol/m²
February 20258.8 µg/m³44 µg/m³70 µmol/m²46 µmol/m²
January 202511 µg/m³50 µg/m³68 µmol/m²51 µmol/m²
December 20249.8 µg/m³49 µg/m³72 µmol/m²63 µmol/m²
November 202412 µg/m³59 µg/m³81 µmol/m²66 µmol/m²
October 202415 µg/m³64 µg/m³81 µmol/m²66 µmol/m²
September 202417 µg/m³61 µg/m³96 µmol/m²84 µmol/m²
August 202422 µg/m³54 µg/m³110 µmol/m²97 µmol/m²
July 202425 µg/m³39 µg/m³116 µmol/m²101 µmol/m²
June 202423 µg/m³37 µg/m³104 µmol/m²98 µmol/m²
May 202424 µg/m³42 µg/m³101 µmol/m²99 µmol/m²
April 202417 µg/m³43 µg/m³90 µmol/m²77 µmol/m²
March 202412 µg/m³46 µg/m³72 µmol/m²64 µmol/m²
February 20249.8 µg/m³45 µg/m³68 µmol/m²57 µmol/m²
January 20249.2 µg/m³45 µg/m³56 µmol/m²43 µmol/m²

Over the last five years the NO2 column averaged 111 µmol/m² in winter against 68 µmol/m² in summer, and the SO2 column 102 µmol/m² against 49 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: 11 µg/m³2005: 12 µg/m³2006: 12 µg/m³2007: 13 µg/m³2008: 13 µg/m³2009: 13 µg/m³2010: 14 µg/m³2011: 13 µg/m³2012: 14 µg/m³2013: 15 µg/m³2014: 14 µg/m³2015: 14 µg/m³2016: 15 µg/m³2017: 15 µg/m³2018: 15 µg/m³2019: 16 µg/m³2020: 16 µg/m³2021: 16 µg/m³2022: 16 µg/m³2023: 17 µg/m³2024: 16 µg/m³2025: 16 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
200411 µg/m³
200512 µg/m³
200612 µg/m³
200713 µg/m³
200813 µg/m³
200913 µg/m³
201014 µg/m³
201113 µg/m³
201214 µg/m³
201315 µg/m³
201414 µg/m³
201514 µg/m³
201615 µg/m³
201715 µg/m³
201815 µg/m³
201916 µg/m³
202016 µg/m³
202116 µg/m³
202216 µg/m³
202317 µg/m³
202416 µg/m³
202516 µg/m³

Every municipality, ranked · Everything we hold for Richmond · 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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