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Air in Breede Valley

Air in 2025 (modelled): nitrogen dioxide near the ground averaged 7.4 µg/m³, under WHO’s guideline of 10; winters 11 µg/m³, summers 3.8 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 20253.3 µg/m³55 µg/m³32 µmol/m²15 µmol/m²
November 20254.6 µg/m³58 µg/m³42 µmol/m²14 µmol/m²
October 20255.1 µg/m³60 µg/m³45 µmol/m²14 µmol/m²
September 20257.7 µg/m³52 µg/m³43 µmol/m²12 µmol/m²
August 202511 µg/m³45 µg/m³45 µmol/m²13 µmol/m²
July 202511 µg/m³39 µg/m³46 µmol/m²16 µmol/m²
June 202511 µg/m³38 µg/m³48 µmol/m²15 µmol/m²
May 202513 µg/m³37 µg/m³50 µmol/m²15 µmol/m²
April 20258.5 µg/m³42 µg/m³46 µmol/m²14 µmol/m²
March 20256.2 µg/m³49 µg/m³45 µmol/m²16 µmol/m²
February 20254.9 µg/m³50 µg/m³41 µmol/m²14 µmol/m²
January 20253.1 µg/m³49 µg/m³34 µmol/m²15 µmol/m²
December 20243.3 µg/m³50 µg/m³32 µmol/m²16 µmol/m²
November 20244.3 µg/m³56 µg/m³35 µmol/m²12 µmol/m²
October 20246.4 µg/m³64 µg/m³38 µmol/m²17 µmol/m²
September 20247.5 µg/m³59 µg/m³39 µmol/m²16 µmol/m²
August 20249.2 µg/m³52 µg/m³38 µmol/m²13 µmol/m²
July 20248.5 µg/m³46 µg/m³38 µmol/m²13 µmol/m²
June 202412 µg/m³35 µg/m³45 µmol/m²20 µmol/m²
May 202414 µg/m³35 µg/m³48 µmol/m²16 µmol/m²
April 20249.3 µg/m³42 µg/m³46 µmol/m²16 µmol/m²
March 20247.2 µg/m³43 µg/m³44 µmol/m²16 µmol/m²
February 20244.6 µg/m³47 µg/m³36 µmol/m²15 µmol/m²
January 20245.3 µg/m³48 µg/m³39 µmol/m²16 µmol/m²

Over the last five years the NO2 column averaged 44 µmol/m² in winter against 35 µmol/m² in summer, and the SO2 column 16 µmol/m² against 15 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: 5.2 µg/m³2004: 5.1 µg/m³2005: 5.0 µg/m³2006: 5.3 µg/m³2007: 5.3 µg/m³2008: 5.3 µg/m³2009: 5.8 µg/m³2010: 6.1 µg/m³2011: 6.0 µg/m³2012: 6.0 µg/m³2013: 6.0 µg/m³2014: 6.2 µg/m³2015: 6.7 µg/m³2016: 6.9 µg/m³2017: 7.5 µg/m³2018: 7.0 µg/m³2019: 7.5 µg/m³2020: 7.9 µg/m³2021: 7.6 µg/m³2022: 8.0 µg/m³2023: 7.0 µg/m³2024: 7.6 µg/m³2025: 7.4 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
20035.2 µg/m³
20045.1 µg/m³
20055.0 µg/m³
20065.3 µg/m³
20075.3 µg/m³
20085.3 µg/m³
20095.8 µg/m³
20106.1 µg/m³
20116.0 µg/m³
20126.0 µg/m³
20136.0 µg/m³
20146.2 µg/m³
20156.7 µg/m³
20166.9 µg/m³
20177.5 µg/m³
20187.0 µg/m³
20197.5 µg/m³
20207.9 µg/m³
20217.6 µg/m³
20228.0 µg/m³
20237.0 µg/m³
20247.6 µg/m³
20257.4 µg/m³

Every municipality, ranked · Everything we hold for Breede Valley · 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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