While huge plumes of methane leaking from gas pipelines have been detected by satellites at individual sites, such as a gas well in Ohio and several pipelines in central Turkmenistan, little has been know about their extent globally.
Now, images captured by an instrument aboard a satellite have been run through an algorithm to automatically detect the biggest plumes of methane streaming from oil and gas facilities worldwide.
These ultra-emitters were spotted pumping out more than 25 tonnes of methane an hour.
That’s «a heck of a lot», says Steve Hamburg at Environmental Defense Fund (EDF), a US non-profit organisation.
Collectively, these contribute about 8 million tonnes of methane a year, about a 10th of the oil & gas industry’s total annual emissions for 2019-20.
Methane is a powerful greenhouse gas that governments recently agreed to slash by 2030..
Turkmenistan was the biggest ultra-emitter, releasing more than a million tonnes of methane between 2019 and 2020.
Russia was 2nd at just under a million tonnes, followed by the US, Iran, Algeria and Kazakhstan.
The US count is probably low because it excluded a major oil & gas region, the Permian basin, due to monitoring difficulties.
By contrast to these countries, other major oil producing countries, including Kuwait and Saudi Arabia, had very few ultra-emitters.
Drew Shindell at Duke University in North Carolina, part of the team behind the analysis, says the big differences between countries gives hope that bad practice – where gas is released to the atmosphere for pipe repairs rather than pumped to another section of pipe – can be improved.
- It shows if we put some effort in, we can have hardly any leaks or intentional releases that are large enough to be seen from space
For the 6 worst countries, tackling those plumes should cost up to $300 less per tonne than it would typically cost to reduce methane from oil & gas facilities in those nations.
A new EDF satellite due to launch next year will scrutinise much smaller but more numerous plumes that make up the bulk of the industry’s emissions.