Hey, I got so angry at those Trump tweets with his cavalier disregard for the future of the planet— of any future but his own— I started a petition at whitehouse.gov. Believe it or not, Trump hasn’t gotten rid of this site yet, where citizens can post petitions and vote on them. (The most popular petitions are about impeaching him. :)
I started this petition to support rather than withdraw from the global accord on mitigating climate change. This is a White House petition, so that the White House "must review it" if it gets enough signatures. Sign and share, if you're of a mind! A withdrawal should not happen on whim and without scientific and public discussion.
https://petitions.whitehouse.gov/petition/support-paris-climate-accords