During tonight's GOP debate, Marco Rubio was asked if he would honor the Miami mayor's request for a pledge to do something about climate change and acknowledge its reality.

"Sure, the climate is changing," Rubio responded. "The climate is changing is because the climate has always been changing. There has never been a time when the climate has not changed."

Rubio said he has long supported mitigation efforts to minimize the effects of climate change, but there's nothing the U.S. can do "to change the weather."

“America’s not a planet, it’s a country,” he said. “I’m not going to destroy the U.S. economy for a law that will do nothing to change the climate.”