Eli5: how can we really know how much CO2 we are emitting anyways?

Question

If it’s not done via satellite and relies on reporting from countries, then it must be very off. Who knows what I burn somewhere in a developing country? Plus, countries might just underreport it anyways

In: Planetary Science

Answer 1

There’s actually a REALLY good video by Simon Clarke, a PhD in Atmospheric Physics, on this exact problem: https://youtu.be/AfKqiadS3TE?si=ySzwUfhCdD8wyf7W

To summarise, satellites can actually detect how much CO2 is in the atmosphere, and by tracking the changes over time, not only can you forecast where the CO2 is going to move (which is actually exactly how weather forecast is done), you can also _hindcast_ the source of the carbon.