"I mean, I'll be 43 this month, but the other thing that perhaps people don't realize, I've served now in public office for the better part of 14 years," Rubio told ABC's Jonathan Karl. "Most importantly, I think a president has to have a clear vision of where the country needs to go and clear ideas about how to get it there."
Part of Rubio's "clear vision" is to cut what he sees as wasteful spending on programs to combat and curb climate change.
"I do not believe that human activity is causing these dramatic changes to our climate the way these scientists are portraying it ... and I do not believe that the laws that they propose we pass will do anything about it, except it will destroy our economy."
If he does run in 2016, Rubio said unlike Rand Paul he will not try to seek reelection to the senate
"I believe that if you want to be president of the United States, you run for president. You don't run for president with some eject button in the cockpit that allows you to go on an exit ramp if it doesn't work out."
When asked about his consistently-declining approval rating, Rubio joked it off.
"It's probably the TIME cover jinx, just like the Sports Illustrated jinx," he said, alluding to a TIME Magazine cover story that ran over a year ago.
ABC's interview was held in in New Hampshire, where Rubio spent last week fundraising and stumping to GOP groups and donors.