(CNN) CNN will host a Democratic presidential town hall in September focused on the climate crisis.

The event will take place on Wednesday, September 4, in New York City. CNN is inviting candidates who meet the Democratic National Committee's polling threshold for the September primary debate to participate, meaning they've reached at least 2% in four approved polls by August 28.

The 2020 Democratic field has been united in promising to combat climate change, with many candidates unveiling policy proposals to address the threat posed by a warming planet. President Donald Trump has pledged to leave the Paris climate accord and has said he does not believe government reports that cast grave warnings about the effects of climate change.

The most prominent proposal put forth by Democrats and backed by multiple presidential candidates has been the Green New Deal, the renewable-energy infrastructure investment plan proposed by Rep. Alexandria Ocasio-Cortez of New York.

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