Story highlights Leonardo DiCaprio says lack of understanding about climate change led to the issue being snubbed during presidential debates

DiCaprio executive produced and stars in a new documentary about climate change called "Before the Flood"

(CNN) Leonardo DiCaprio traveled to almost every corner of the globe while making his new climate change documentary, "Before the Flood." But back in America, the Oscar-winning actor wishes more attention was being paid to the issue, particularly during the recent presidential debates.

"This issue has become so polarizing while at the same time one of the least discussed -- and probably least understood -- of our political discourse," he told the crowd at a Los Angeles screening of his film on Monday night. "Not one question about climate change was asked during the presidential or vice presidential debates — not one."

This is mostly true.

During the three presidential debates and the vice presidential debate, no question about climate change was directed to the candidates from moderators. Candidates' sole question regarding their energy policy was asked at the town hall debate by audience member Ken Bone , whose red sweater arguably received more attention than the candidates' response to his query.

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