So apparently someone was concerned about global warming way back in 1957.
The full movie can be found on the DVD Hemo the Magnificent / Unchained Goddess (1957) You can get it at Amazon or through Netflix.
Note — America had 171 million people vs. 303 million today. There are about 125 million cars on the road today. If we use the same ratio, there would have been approx 70 million cars on the road back then, but more than likely a lot less. The point is we were probably putting out 25% of the world’s greenhouse gasses back then.