There really is a smoking gun-90 to be exact...the fossil fuel industry knew and kept hidden that their massive pollution would create catastrophic weather events by around 2000 and human extinction by 2030....if we're lucky, because right now science cannot keep up with the earth changes.

http://www.sciencemag.org/news/2016/08/just-90-companies-are-blame-most-climate-change-carbon-accountant-says