The site, Inside Climate Change, has done an excellent series of articles on Exxon's attempt to fight public disclosure that it knew  years ago that fossil fuel emissions were leading and would ultimately lead to catastrophic greenhouse effects for Earth...the latest on Exxon's fight against what their lawyer calls the  'un-American' pursuit of disclosure...

http://insideclimatenews.org/news/21042016/exxon-competitive-enterprise-institute-cei-climate-change-fraud-investigation-first-amendment-rights

Exxon internal memo from 1981 identifying catastrophic effects on Earth by 2030 by fossil fuel pollution

"toward the end of the 1980s, Exxon curtailed its carbon dioxide research. In the decades that followed, Exxon worked instead at the forefront of climate denial. It put its muscle behind efforts to manufacture doubt about the reality of global warming its own scientists had once confirmed. It lobbied to block federal and international action to control greenhouse gas emissions. It helped to erect a vast edifice of misinformation that stands to this day." (from "Exxon's Own Research confirmed Fossil Fuel's Role In Global Warming Decades Ago"

 article, Inside Climate Change,September 2015, by  NEELA BANERJEE, LISA SONG AND DAVID HASEMYER.)