Speaking to an audience at a town hall meeting in Carroll, Iowa, Wisconsin Governor Scott Walker took on President Obama’s comments made in a commencement speech to the U.S. Coast Guard earlier this year about the severity of the threat of climate change.

“We have a president… who proclaimed that the greatest threat to future generations was climate change… Well, Mr. President, I respectfully disagree,” Gov. Walker said.

Governor Walker has not detailed his position on climate change, though he signed a “no climate tax” pledge in 2008.