John von Neumann on CO2, From 1955

"The carbon dioxide released into the atmosphere by industry's burning of coal and oil--more than half of it during the last generation--may have changed the atmosphere's composition sufficiently to account for a general warming of the world by about one degree Fahrenheit."

-- John von Neumann, "Can we survive technology?" Forbes, June 1955.

Here's a compilation of many more early papers and articles on CO2 and climate that I've been gathering....