Svensmark cites coronal mass ejections as ‘natural experiment’ on clouds

What was said

"this is what I call the natural experiment for testing this uh this uh idea. So when we have these events, I can then look at uh satellite observations of earth clouds and see if anything happens."

Svensmark argues that coronal mass ejections, which temporarily reduce incoming galactic cosmic rays, can be used to test whether ionisation affects aerosols and cloudiness. He says satellite datasets show dips in aerosols and cloud measures days after such events, consistent with time needed for particles to grow into cloud condensation nuclei.