Not the countries themselves, but satellites that will soon measure carbon dioxide emissions

Reducing greenhouse gas emissions has always been a major topic at all climate conferences, including during the climate summit in Egypt. Remarkably, emissions have so far been estimated by the countries themselves. Experts see the use of satellite data as a major advance, with potentially far-reaching consequences.

“You can imagine that sometimes you end in your favor when you mark your test,” says Detlev van Vouren, a climate researcher at Utrecht University. Participates in the Global Carbon Project, prof projects of climate scientists who independently calculate global greenhouse gas emissions.

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

The Washington Post compared the country reports to expert measurements and estimates. Differences shifted enormous. There is a gap of at least a few billion tons between country 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 the source of the emissions. “Not only for an effective climate policy, but also to be able to check whether countries are really doing what they promise.”

Measuring exhaust gases is complex, stresses Pepijn Veefkind, scientific lead at KNMI. Participates in satellite projects.

“If the measurement were simple, of course we would have done it a long time ago. Technically, it’s hard to trace carbon dioxide accurately. After all, it stays in the atmosphere for a long time, it leaves traces for a long time. That means you can’t trace the source.” Even now. It’s very difficult to trace back. It’s like trying to see a candle, while you’re looking at the light in a big lamp.”

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

In four years, a new European satellite will map emissions of carbon dioxide, the most important greenhouse gas, worldwide.

It’s a very big step forward, says Vivekind. “The advantage of satellites is that you can check which countries are reporting and what is real. There have been examples in the past where satellite monitoring played a positive role, for example with regard to air quality in China. Sometimes companies want to use satellites to confirm It has reduced emissions, so it works both ways.”

Manfredi Caltagirone of the United Nations Environment Program says the UN wants to use the data to tackle major sources of emissions.

“The UN cannot force anyone to do anything. We hope that there will be cooperation. And that people will realize that data becomes public 45 to 75 days after it is discovered. Including their reaction, whether or not they take action.”

However, it remains questionable whether more data on the origin of greenhouse gases would actually lead to fewer emissions, as the United Nations acknowledges.

Caltagirone: “We want to transfer the data to the right people, so that they can turn off the tap on oil and gas facilities. On the one hand, we want to show that the world is changing and becoming transparent.”

Watch here the episode of Nieuwsuur’s #Ophef series on common climate misconceptions: