At least according to the New York Times:
The basic idea is that natural gas production might increase, and thus reduce the use of coal and oil, with the end result of generating less CO2. Quoting from the article:
"...real progress on reducing carbon in the atmosphere has been driven so far by specific domestic energy, industrial and innovation policies, not emissions targets and timetables or international agreements intended to legally constrain national emissions.”
Here's an interesting little factoid: the original title of this article was:
"Trump's Climate Policies May Work Out in the Planet's Favor"
Someone at the NYT apparently decided that made Trump look too good. Now the headline reads:
"Earth Isn't Doomed Yet: The Climate Could Survive Trump Policies". (you can still see the original title in the URL)
Gotta love the way the NYT sticks to the narrative. And you wonder why so many of us wingnuts distrust the MSM.