CSU Channel Islands Professor of Environmental Science Sean Anderson, PhD., says pulling out of the Paris Agreement by any degree might be catastrophic.
New York will be either flooded frequently or behind dikes, New Orleans look increasingly like an Island and Miami will simply be abandoned. The bigger issues relate to our food, water, and material flows which large cities are inherently dependent.
Wine will be produced in Canada, the American farm belt won't be as productive or profitable, variable/less predictable weather and growing isolation of the wealthier world from the poorer nations that bear the greatest burdens/most civil unrest as their regions descend into chaos and famine.
Regardless of what POTUS announces, Dr. Anderson can predict the results on the environment.
He can also be specific about the effects on California.