“ ‘You know, I’ve always thought Trump has a right to his opinions, but doesn’t have a right to his own facts.’ ”

That’s former New York Mayor Michael Bloomberg weighing in on President Donald Trump’s insistence that climate change is not real and that he doesn’t believe the conclusions reached by his own science advisers in a recent report.

Bloomberg was talking on Sunday’s “Meet the Press,” which dedicated a special program to climate change (see full NBC News transcript).

Host Chuck Todd started the program by telling viewers he would offer a deep dive into the subject that would not include any climate-change deniers. “The science is settled, even if political opinion is not,” Todd said before introducing a panel that included Bloomberg and California Gov. Jerry Brown, both longtime climate activists.

Trump’s decision to pull the U.S. out of the Paris agreement, while disappointing to those concerned about irreversible environmental damage, has not fully killed the effort to meet the goals of that treaty, which include curbing warming over the century to 2 degrees Celsius, said Bloomberg. Insurers have warned that any greater warming would make the world uninsurable.

“We’re halfway there already, and there’s seven years left to go,” he said. That’s mostly thanks to efforts made by the private sector, individuals and companies. “It would be a lot more helpful if we had a climate champion rather than a climate denier in the White House,” Bloomberg said, but the U.S. can and must meet the goals of Paris if it is to continue to succeed economically, and any credible presidential candidate needs to have a plan to mitigate the effects.

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“The presidency is not an entry-level job,” said Bloomberg.

Brown compared the challenge of fighting climate change to the fight against the Nazis in World War II. “I would point to the fact that it took Roosevelt many, many years to get America willing to go into World War II and fight the Nazis. Well, we have an enemy — though different, but, perhaps, very much devastating in a similar way. And we’ve got to fight climate change. And the president’s got to lead on that.”

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Trump’s own advisers warned in a report released on the Friday after Thanksgiving that, without significant reductions in greenhouse-gas emissions, climate change will cost the U.S. economy billions of dollars. The report estimated that every one-degree-Celsius increase in global temperatures would result in a loss of about 1.2% of GDP.