Arizona Sen. John McCain, one of the first Republican lawmakers to pursue federal climate change policy, said he is “very much afraid about what the world is going to look like for our children and grandchildren” if we don’t address climate change.

“I think that climate change is real,” he said at an event in Sydney, Australia. “I think that one of the great tragedies of our lives is the Great Barrier Reef dying [and] the environmental consequences of that.” The longtime senator expressed his support for keeping the U.S. a party to the Paris climate accord.

“I would like to see us … either accept the agreements as were made by the Obama administration or suggest modifications which would make it palatable for us and acceptable to us to join,” he said.

He joins a handful of his senate colleagues in pressing for the U.S. to maintain a global leadership role.