The aerosol effect cited for the cooling from from 1940 to 1970 has only been speculated. The IPCC cites it as the “most likely” cause for the 30 year cooling period. There has yet to be a quantatative explanation or description of this link. The truth is aerosol effect is one of the least understood variables in climate prediction. In some scenarios it actually can produce warming. (No references, go find them!)
The IPCC (not surprisingly) had to find an explanation that would not conflict with the over-arching theory of global warming. The aerosol effect can neither be confirmed or denied. Hence, the notion that if you can’t prove me wrong, I must be right. However in true scientific inquiry, one does not have to refute the assertion. It is the one making the claim that must produce the convincing evidence.
There has been no definitive proof that the 1940 to 1970 cooling was caused by aerosols. It may have been or may not.
As an example, if I cross a bridge and it collapses under me, you cannot say whether I was the cause without further investigation. I may have caused it or it may have been bad timing.
