"While President Trump has vowed to formally withdraw from the Paris climate agreement, sparking international outrage, it doesn’t necessarily mean the end of U.S. involvement forever. A future president could have us back in the agreement in as little as 30 days, legal experts say.

Under the rules of the Paris agreement, parties are allowed to exit and reenter as they choose, although withdrawing is a much lengthier legal process than returning. And there are no provisions stipulating how much time has passed after withdrawal before a nation can begin the process of rejoining the agreement.

“A subsequent president would thus be able to submit a document stating the United States’ intention to become a party to the Agreement as soon as she or he wanted to,” Michael Burger, executive director of the Sabin Center for Climate Change Law at Columbia Law School, said in an email to The Washington Post — although he added that such an action is certainly outside the norm."

Chelsea Harvey reports for the Washington Post June 5, 2017. [2]