President Trump declared that the United States would leave the Paris climate agreement, following months of infighting among Trump’s staff that left the world in suspense. He said he hopes to negotiate a similar deal that is more favorable to the U.S.

This move is one of several Obama-era environmental milestones that Trump has dismantled. And all the while, a new study shows global temperatures might be rising faster than expected.

Leaving the agreement displaces the U.S. from a stance of global leadership and leaves it out of an agreement that includes every other country in the world. Nicaragua — which originally refused to join because the Paris Agreement didn’t go far enough — joined the agreement on Oct. 23, 2017. And Syria, which was also not part of the initial agreement, announced its intention to join on Nov. 7, 2017.Even countries such as Liberia and the Democratic Republic of the Congo, which are among the poorest in the world and were struggling with an Ebola epidemic at the time, have signed on.