A 1979 memo from Exxon’s R.J. Campion to W.W. Madden referencing Bill Slick’s need for information on atmospheric CO2 buildup as a potential emerging issue for the American Petroleum Institute to consider. Exxon recommended that this is not a high priority and referenced the Exxon Research and Engineering pilot “Greenhouse Project” study that measured CO2 in the air and water over Exxon tanker routes.