Satellite data lays scale of methane leaks bare

Methane, a powerful greenhouse gas, is leaking from industry sites at rates equivalent to the annual carbon emissions of France and Germany combined, a new analysis using satellite data showed Tuesday.

Using imaging data gathered by the European Space Agency's Sentinel-5P monitoring mission, the study shows more than 100 "high-volume emission events" worldwide from gas storage and transmission facilities.

These events alone emitted around 20 million tonnes of methane -- the short-term equivalent to releasing 1.8 billion tonnes of carbon pollution.

"The good news is most of these are man-made and can easily be addressed through action by individual companies, governments and regulators," said Antoine Rostand, CEO of Kayrros, an asset observation platform that conducted the analysis.

While methane only stays in the atmosphere a fraction of the time that CO2 does, over a period of decades it is dozens of times more potent as a greenhouse gas.

Overall, greenhouse gas emissions from energy have risen globally nearly every year in the last decade, despite the 2015 Paris climate deal mandating their reduction.

The United Nations says that manmade emissions must decline 7.6 percent annually by 2030 to limit global warming to 1.5C above pre-industrial levels -- the more ambitious cap laid out in the Paris deal.

Claus Zehner, Sentinel-5P mission manager at ESA, said satellite monitoring of methane leaks could help industry "support the reduction of global emissions and slow down climate change".

The Kayrros analysis has not been reviewed by scientists but has been shared with the European Commission.

Commenting on the project, Gunnar Luderer and Nico Bauer, climate economists at the Potsdam Institute for Climate Impact Research, said that it may overestimate the warming impact of methane leaks.

"Still, however, the annual leakage of 20 Mt of methane from 100 point sources mostly in the energy industry is an astonishing loss that is worth further validation," they told AFP.

They said that the leaks alone were worth nearly two thirds of all natural gas use in France every year, with an industry impact of roughly four billion euros (USD 4.4 billion).

"Economists would expect that such leakage would be avoided for pure cost reasons," said Luderer and Bauer.

"In any case, regulatory intervention could lead to lower emissions with economic benefit.