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Air in Lephalale

Air in 2025 (modelled): nitrogen dioxide near the ground averaged 14 µg/m³, 1.4 times WHO’s guideline of 10; winters 20 µg/m³, summers 8.1 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 20259.7 µg/m³40 µg/m³52 µmol/m²64 µmol/m²
November 20258.7 µg/m³44 µg/m³55 µmol/m²59 µmol/m²
October 20259.9 µg/m³59 µg/m³67 µmol/m²84 µmol/m²
September 202511 µg/m³60 µg/m³69 µmol/m²96 µmol/m²
August 202520 µg/m³50 µg/m³86 µmol/m²106 µmol/m²
July 202522 µg/m³36 µg/m³98 µmol/m²114 µmol/m²
June 202522 µg/m³37 µg/m³100 µmol/m²121 µmol/m²
May 202520 µg/m³37 µg/m³92 µmol/m²125 µmol/m²
April 202514 µg/m³37 µg/m³68 µmol/m²85 µmol/m²
March 202512 µg/m³38 µg/m³65 µmol/m²77 µmol/m²
February 20258.0 µg/m³36 µg/m³58 µmol/m²67 µmol/m²
January 20259.1 µg/m³37 µg/m³57 µmol/m²62 µmol/m²
December 20248.8 µg/m³45 µg/m³53 µmol/m²68 µmol/m²
November 20248.8 µg/m³55 µg/m³57 µmol/m²71 µmol/m²
October 20249.3 µg/m³68 µg/m³71 µmol/m²107 µmol/m²
September 202412 µg/m³63 µg/m³69 µmol/m²84 µmol/m²
August 202420 µg/m³50 µg/m³87 µmol/m²115 µmol/m²
July 202423 µg/m³35 µg/m³111 µmol/m²116 µmol/m²
June 202420 µg/m³39 µg/m³91 µmol/m²108 µmol/m²
May 202421 µg/m³41 µg/m³100 µmol/m²151 µmol/m²
April 202412 µg/m³42 µg/m³73 µmol/m²102 µmol/m²
March 20248.7 µg/m³42 µg/m³61 µmol/m²86 µmol/m²
February 20248.1 µg/m³42 µg/m³55 µmol/m²84 µmol/m²
January 20248.6 µg/m³42 µg/m³55 µmol/m²73 µmol/m²

Over the last five years the NO2 column averaged 95 µmol/m² in winter against 55 µmol/m² in summer, and the SO2 column 115 µmol/m² against 67 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: 11 µg/m³2006: 12 µg/m³2007: 12 µg/m³2008: 12 µg/m³2009: 13 µg/m³2010: 13 µg/m³2011: 13 µg/m³2012: 12 µg/m³2013: 12 µg/m³2014: 12 µg/m³2015: 12 µg/m³2016: 12 µg/m³2017: 12 µg/m³2018: 12 µg/m³2019: 13 µg/m³2020: 12 µg/m³2021: 13 µg/m³2022: 13 µg/m³2023: 14 µg/m³2024: 13 µg/m³2025: 14 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
200511 µg/m³
200612 µg/m³
200712 µg/m³
200812 µg/m³
200913 µg/m³
201013 µg/m³
201113 µg/m³
201212 µg/m³
201312 µg/m³
201412 µg/m³
201512 µg/m³
201612 µg/m³
201712 µg/m³
201812 µg/m³
201913 µg/m³
202012 µg/m³
202113 µg/m³
202213 µg/m³
202314 µg/m³
202413 µg/m³
202514 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 Lephalale · 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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