(CNN) Ten Democratic candidates for president have qualified for next month's Climate Crisis Town Hall, which will air exclusively on CNN platforms.

CNN is devoting the evening of Sept. 4 to the climate crisis. Eight of the Democratic candidates initially accepted CNN's invitation to discuss this critically important issue: former Vice President Joe Biden; Sen. Cory Booker of New Jersey; South Bend, Indiana, Mayor Pete Buttigieg; Sen. Amy Klobuchar of Minnesota; former Rep. Beto O'Rourke of Texas; Sen. Bernie Sanders of Vermont; Sen. Elizabeth Warren of Massachusetts; and businessman Andrew Yang.

Sen. Kamala Harris of California initially declined CNN's invitation, citing a scheduling conflict. But her campaign informed CNN on Tuesday morning that the senator would participate.

"We were happy to change our schedule to accommodate such a critical conversation," Harris spokeswoman Lily Adams said. "As Senator Harris has said, this is a climate crisis and is one of the most urgent reasons we need a new president."

With the release of a CNN poll on Tuesday, former Housing and Urban Development Secretary Julián Castro reached the polling threshold to participate in the event. A Castro campaign spokeswoman said he would attend.

Read More