Sounds like a stupidly easy question to find out with a quick internet search, but it’s not.
I don’t want to know the average surface temperature, or the average ocean surface water temperature, or read another article about climate change.
But that’s all I found in the past hour.
I’d like to know the average temperature of all molecules that comprise earth, or a best guess scientific estimate.
For what it’s worth this won’t change the result in any meaningful way. Both in terms of atom count and atom mass the atmosphere makes up only a tiny fraction of the earth’s material.
If you’re taking an average by unit of volume, it absolutely matters
By about 4.8 percent.