not the countries themselves, but satellites will soon measure CO2 emissions

The reduction of greenhouse gas emissions is always a central theme in all climate conferences, even during the climate summit in Egypt. Surprisingly enough, emissions have so far been estimated by the countries themselves. Experts see the use of satellite data as a game changer, with potentially far-reaching consequences.

“You can imagine that from time to time it ends up in your favor when you grade your test,” says Detlef van Vuuren, a climate researcher at Utrecht University. He is involved in the Global Carbon Project, a project of climate scientists who independently calculate global greenhouse gas emissions.

All countries now report their emissions to the United Nations (UN) via so-called self-reports. The danger is that countries adopt creative accounting practices. And this is happening now.

The Washington Post compared the national reports with expert measurements and estimates. The differences turned out huge. There is a gap of at least a few billion tons between national reports and independent estimates. This is roughly equivalent to the emissions of two billion cars.

According to Van Vuuren, it is important to be able to directly measure where the emissions are coming from. “Not only for an effective climate policy, but also to be able to check whether countries actually keep what they promised.”

Measuring exhaust gases is complex, points out Pepijn Veefkind, chief scientist at KNMI. He is engaged in satellite projects.

“If measuring were easy, of course we would have done it a long time ago. Technically speaking, it is difficult to track CO2 accurately. After all, it stays in the atmosphere for a long time, leaves traces for a long time. going back to the source. very difficult to go back to it. It is like trying to see a candle, while looking against the light of a large lamp.”

Satellites are already searching from space for those sources of greenhouse gases. Currently only the largest emitters can be seen, but zooming in is increasingly possible as well.

In four years, a new European satellite will map CO2 emissions, the world’s most important greenhouse gas.

A big step forward, says Veefkind. ‘The advantage of satellites is that you can check what countries report and what is real. There have been examples in the past where observation by satellites has played a positive role, for example regarding the quality of the air in China. Companies sometimes want to use satellites to confirm that they have low emissions, so it works both ways.”

The United Nations wants to use the data to tackle key emitters, says Manfredi Caltagirone of the United Nations Environment Programme.

“The United Nations cannot force anyone to do anything. We hope there can be cooperation. And that people realize that the data becomes public 45 to 75 days after it is detected. Including their reaction and whether or not they act” .

However, it is still debatable whether the availability of more data on the origin of greenhouse gases will actually lead to lower emissions, even the UN acknowledges.

Caltagirone: “We want to transmit the data to the right people, so they can turn off the tap of the oil and gas plants. Instead, we want to demonstrate that the world is changing and becoming transparent”.

Watch the episode of our series Nieuwsuur #Ophef here, on common misconceptions about climate: