It wasn’t a big concern during the 2016 campaign — presidential debate moderators didn’t even bring it up. But now, whether or not President Trump accepts it, climate change has become a matter of intense focus, because of the U.S. withdrawal from the Paris climate agreement.
Based on what we’ve seen so far, there’s little indication that Trump accepts the main tenet of climate change science — that humans are the core driver of the warming of the planet — and good reason to think this probably mattered in his decision on Paris.
Indeed, Monday morning Politico’s Playbook even gave reason to think that Trump may remain a skeptic, reporting on what had been “overheard at Trump National”:
Trump discussing his decision to pull out of the Paris climate agreement over lunch after playing a round of golf Sunday. Trump’s post-Paris analysis: they can’t even get the weather report right, so how come they think they can get that right?
(Actually, weather reports are pretty accurate these days.)
Whatever Trump thinks, his administration has rarely denied the science of climate change outright. Rather, it has tried to finesse the matter by arguing that there’s some human role in climate change, but not saying how much. Or as Nikki Haley, U.S. ambassador to the United Nations, put it on CNN recently: “President Trump believes the climate is changing, and he believes pollutants are part of that equation.”
But Haley’s statement — which suggested that the human contribution to climate change could be a mere 10 percent, and is similar to Trump’s own admission last year that there is “some connectivity” between humans and climate change — is not the scientific consensus view. “It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century” is what the U.N. Intergovernmental Panel on Climate Change concluded.
During a White House press briefing Friday, Scott Pruitt, head of the Environmental Protection Agency, was asked multiple times whether Trump believes in climate change. Pruitt demurred, suggesting it didn’t come up in White House discussions about the Paris agreement — but he also described his own views, saying that humans contribute to climate change “in some manner.” On Sunday, he added on ABC’s “This Week” that “the president has indicated the climate changes.”
All of this, too, is weaker than the expert consensus that humans are the overwhelming driver of the problem. Pruitt’s EPA has taken down an informational website on climate change that affirmed that consensus.
Beyond such statements — and the recent Politico report — there has been little clarification of Trump’s views. But given the evidence, and that he was prone to calling climate change a “hoax” on Twitter before his election, it’s doubtful he now embraces the idea that it is mainly caused by humans.
And this matters to his decision on Paris. Simply put, if you’re not sure humans are the main force behind climate change, then the urgency of cutting greenhouse gas emissions would naturally seem far less compelling.
Consider what the president did not say when he addressed the nation on this subject.
Pruitt argued Friday that Trump decided to exit the Paris climate deal for economic reasons, so the science of climate change was not really at issue. “The focus remained on whether Paris put us at a disadvantage. And, in fact, it did. It put us at an economic disadvantage,” Pruitt said, in response to one of the many questions that he received about the reality of climate change.
Yet experts have demonstrated that climate change has its own economic costs, because it causes many types of damage to the world and to the United States. If you believe it is real and driven by humans, you would tend to weigh those costs significantly and include them in your decision-making process.
Trump and Pruitt don’t seem to do that. Take, for instance, the main study that Trump cited in the Rose Garden, conducted by NERA Economic Consulting for the U.S. Chamber of Commerce and the American Council for Capital Formation, a business-friendly group, to show the burdensome costs of complying with the Obama climate pledge under the Paris agreement. That study explicitly states that it does not weigh the damages caused by climate change.
“It does not take into account potential benefits from avoided emissions,” the study notes in a footnote — benefits that naturally would include reduced climate-related damage. “The study results are not a benefit-cost analysis of climate change.”
Yet it is hard to dispute that there are economic costs to worsening climate change. For instance, the EPA found that in the year 2100 alone, the United States could save $3.1 billion in coastal damage and adaptation expenditures, $4.2 to $7.4 billion in costs for adapting roads and highways, and $100 billion in lost labor productivity, if the world takes action on global warming. And those are just savings in a single year — they would be much larger if considered over many years.
But there is little evidence that the costs of human-driven climate change factored into Trump’s decision.
At the same time, we know a great deal about the deliberations at the White House over the Paris agreement. We know that Trump heard from business leaders who favored staying in the agreement. We know that he heard from European leaders — and that their entreaties apparently backfired.
But we haven’t heard that he consulted scientists about what is happening with the climate — and indeed, Trump has not appointed a presidential science adviser who might have been able to unpack this for him. That’s another indication climate change science does not seem to have factored into his decision.
Finally, as experts will tell you, the science of climate change implies urgency. There is very little time left for the world to reduce its emissions, if we want to avoid warming the planet by an amount that scientists would consider dangerous.
This urgency was a key factor in bringing countries together in Paris, where they agreed to an accord that ideally aims to limit warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels — an extremely stringent target that reflects a growing scientific realization that severe impacts from climate change are already occurring.
Trump did not signal any sense of urgency about climate change in his Rose Garden speech. He said instead that he would try to renegotiate the Paris agreement to get the United States a better deal, a process that could take a long time, if it ever did happen (and there’s no indication it would).
So in sum: Trump has regularly cast doubt on the scientific consensus on climate change in the past. Subsequent clarifications of his views and statements by the administration on climate change have stopped short of acknowledging the central conclusion of climate change science. And finally, Trump’s decision about the Paris agreement doesn’t seem to reflect the kinds of considerations that the science of climate change would engender.