Former vice president and climate change activist Al Gore is concerned that a potential Donald Trump presidency could roll back progress in the fight against climate change.
"He has said some things on the climate crisis that I think should concern everyone,'' Gore said in an interview with NBC's "Today" show.
Trump has called climate change a hoax created by China.
In the Oscar-winning documentary "An Inconvenient Truth," Gore used charts and graphs to make the connection between increasing carbon emissions and the changing climate.
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To mark the 10th anniversary of the film's release on Tuesday, Paramount is offering free downloads of it on Amazon, XFINITY on demand, iTunes and other digital retailers.