KEY POINTS
  • The U.S. officially rejoined the Paris Agreement on climate change. 
  • “We have to ratchet up the commitments now if we are to stay on course to averting a catastrophic three degree Fahrenheit warming,” said scientist Michael Mann.
  • “The world has moved on from American leadership on climate and will be skeptical of our commitment to stay engaged,” said Joel Rubin, a former deputy assistant secretary of state in the Obama-Biden Administration.

Scientist Michael Mann argued that the United States must go "well beyond those Paris commitments" as President Joe Biden rejoined the Paris Climate Agreement Friday. 

"We have to ratchet up the commitments now if we are to stay on course to averting a catastrophic three degree Fahrenheit warming," said Mann, the author of "The New Climate War," during a Friday evening interview on CNBC's "The News with Shepard Smith." "We have to increase our commitments and the other countries of the world have to do that."