[ClearCase_guy]

The last time we saw this phenomenon was in 1999, when a sudden drop in the solar wind caused Earth's magnetosphere to swell outwards, increasing its volume 100-fold.

I believe that under normal circumstances, the amount of carbon dioxide in the atmosphere is 0.04% -- which is a tiny percentage. So, in 1999, wouldn't the percentage have dropped to 0.0004%? And if so, did this affect global warming?

[zeestephen]

Re: "CO2 - dropped to 0.0004?"

I had the same thought until I realized that oxygen, after the same incident, would drop to 0.21% and air pressure would drop to 0.147 psi, which, clearly did not happen.

And, people on the opposite side of the planet would be instantly crushed by 1,470 psi air.

Perhaps gravity is strong enough to hold the lower atmospheric layers in place, and just the rarefied layers are pulled further into space?

Like you, I instantly wondered what the climate consequences would be after a solar event like this.

Most likely, any research that suggests the 2019 event heated the atmosphere would be suppressed, and the researchers would be expelled from the academic community.