It aimed to alert american people about the the risks of unrestrained pollution. Al Gore was well known for his passionate appeals towards the global warming and general risks to the environment not only during his presidential candidature, but both back and forth. And was frequently discredited. During 1992 presidential campaign, the current president's father, George H.W. Bush, referred to him as the 'Ozone Man', when stating that if he was elected, America would suffer an unemployment crisis.
However, with the worldwide rising consensus on global warming along the following decade, his warnings began to sound somehow prophetic. He had his work that first started as a slide presentation, turned into a book and a documentary film in 2006, both entitled 'An Incovenient Truth'.