The report had also been criticised by NUM as a campaign to have Eskom privatised through the back door of the Independent Power Producers.
Fact-checking organisation Africa Check has questioned how Greenpeace came to rank Mpumalanga’s air the dirtiest in the world, suggesting the methods used were unfair.
Africa Check released its article this week following one by Greenpeace in October 2018.
It said the Greenpeace finding were flawed and the methods used to come to the conclusion that Mpumalanga air was the world’s dirtiest made “unsound comparisons”.
The environmental group Greenpeace based its report on satellite data that showed the province had the largest air pollution hotspot when compared to other countries, such as China, India and the US.
It said it produced the largest quantity of nitrogen dioxide emissions – which comes from combustion such as in car engines or when coal and gas are burned for energy and heavy coal use by Eskom’s 12 coal-powered plants was blamed for this.
Melita Steele of Greenpeace told Africa Check that the information on Mpumalanga’s air being dirtiest was from a satellite operated by the Dutch government and the European Space Agency launched in 2017.
She said Greenpeace’s finding was based on a data that covered the period 1 June to 31 August 2018.
These satellites monitor the quantity of dirty air “from a powerful eye in the sky”, Steele said.
Africa Check found that the satellite used by Greenpeace could not show at what height the nitrogen dioxide was situated.
Instead the satellite only showed that there was a certain amount of the gas in the entire column of the atmosphere.
Africa Check also found the nitrogen dioxide produced by these power stations were generally emitted at levels higher than where people breathe.
If anybody needed to find out how much pollution is in the air that people breathe, other methods such as ground-based and aircraft measurements should be used with satellite measurements, experts told the facts-checker.
“A significant fault with Greenpeace’s analysis was that they jump from the concentration in the aerial density and emissions to say that the high number is equivalent to a high concentration at the ground level,” one expert told Africa Check.
The department of environmental affairs said the air we breathe was still below the national air standards, which should not be higher than 21 microgrammes per litre.
Last month Professor Rebecca Garland from the Council for Scientific and Industrial Research told a Parliamentary committee that although Mpumalanga’s air was dirty it’s unfair to say it’s the dirtiest worldwide in comparison with other countries.
There were a number of reasons for this, she told Parliamentarians.
These included the seasons. Greenpeace’s data spanned South Africa’s winter months.
Therefore in winter the emissions would be most visible to satellites due to low dispersion. In eastern China, the eastern US and much of Europe, this peak occurs in January.
“This is comparing our peak almost to one of their lower periods. So it’s not quite fair. We would need more long-term measurements to say that,” Garland said. This would be at least a year’s worth of data, she told Africa Check.
Mpumalanga’s highveld was at a higher altitude, also making emissions more visible to the satellite, she said.
(edited by MLM)
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