Great point. I think if someone does something in the air over their property that causes harm to others, then they should be held accountable. These things would need to be worked out by individuals and I'm sure all sorts of innovative, voluntary solutions would be found.
Also, another question to think about would be.....if the claim is made that someone doesn't have property rights to the air above their land, then who would have claim over it? Who would take responsibility for that air space?
The space above your property is much different from the atmosphere above it. The space is yours but the atmosphere is public property.
You can do anything with the space but you will need public approval for the atmosphere to be changed. Basically all your neighbours in the affected area.