Leaking oil and gas installations and coal mines, but also garbage dumps. This collects the world’s largest point sources (sources collected at one location) of flowing methane. Dutch researchers have mapped out these sources for the year 2021, based on measurements with the satellite instrument Tropomi, which determines concentrations of air pollutants such as methane, ozone and particulate matter. The map was formed last weekend during the climate summit in Sharm-el-Sheikh, Egypt, says co-author Ilse Aben. She is a senior researcher at the Netherlands Institute for Space Research (SRON) and professor by special appointment of satellite remote sensing of the atmosphere at the Free University in Amsterdam. The summary has yet to be published in a scientific journal, but the researchers have already published on aspects such as methane emissions from landfills in Delhi, Mumbai, Lahore and Buenos Aires.
Are there any surprises between the emitters?
“I was extremely surprised how many of those big emitters there are. We had no idea about that beforehand,” says Aben.
It sounds like bad news.
“Yes. But at the same time, it offers a golden opportunity to quickly take major steps in reducing methane emissions.”
A year ago, at the Climate Summit in Glasgow, nearly a hundred countries made an agreement (the Global Methane Pledge) to reduce global methane emissions by 30 percent by 2030 by 2020. Methane is after CO2 the main events. 130 countries have now joined the initiative.
In addition, an initiative was launched in Glasgow that will improve methane measurements and reporting. And this Monday, the UN is unveiling the start of an alert system that governments and companies whose major methane sources are discovered.
The results achieved are comparable to the oil and gas sector. Is that right?
Landfill also appears to be an important source of methane, but it is a lot more complex to address than the leaks we see in the oil and gas sector. For example, in western Turkmenistan, but also in countries such as Algeria, oil fields that bring up natural gas, which is normally flared off, but that doesn’t always seem to happen.”
“We can only speculate on that. Maybe there’s something wrong with the installation. It may also be that the flame has gone out without being noticed or dissolved.”
Flaring converts methane into CO2. Isn’t that just as bad?
„From a climate point of view you prefer CO2 than methane, because methane is much stronger health. But of course it’s best not to let them both go up in the air, and to catch the gas.”
Is it possible to determine with Tropomi whether the source of methane is a garbage dump or a leaking gas installation?
“That is difficult in most cases. You have to zoom in further that far. We pass on our data to the Canadian GHGSat. There they can zoom in on a source, with a resolution of 25 by 25 meters, and then you can see exactly what is leaking.”
What share do the now mapped super emitters have of the total, deadly emissions of methane from humans?
“We are not counting on that yet.”
Is this the final map?
“No, from some sources we have not yet determined what exactly it is about. We just made a special map with more than a hundred garbage dumps worldwide that emit quite a bit of methane.”
You have not found any methane super emitters in the Netherlands.
“No, but that says nothing about how much methane the Netherlands emits. We haven’t focused on those super emitters so far because the low-hanging fruit forms if you want to lower methane emissions. The emissions from the Netherlands are mainly due to livestock farming, which is a more extensive source.”
A version of this article also appeared in the newspaper of November 15, 2022