President Donald Trump’s reactions to a far-reaching federal report on climate change—including saying “I don’t believe it” when asked about the report’s grim economic predictions—have pushed into the background the significance of the report itself.

Generally, when queried about the human contribution to climate change and the catastrophic consequences identified by the majority of climate scientists, the president has hovered somewhere between being a skeptic and a denier, but it is often hard to pin down Trump’s views with any certainty. For example, before expressing his disbelief about the report’s economic conclusions, he said he had “looked at” the report and called it “fine.”

Congressionally mandated

The report, volume II of the Fourth National Climate Assessment (NCA4), is required by the 1990 Global Change Research Act. Developed under the auspices of the U.S. Global Change Research Program, NCA4 is the work of 300 authors from federal, state, and local governments, industry, academia, tribal organizations, and nongovernment organizations, which drew on “over 6,000 unique references.” Federal participation was provided by 13 agencies headed by the National Oceanic and Atmospheric Administration and including the EPA and the Departments of Defense, Energy, Agriculture, Commerce, Health and Human Services, the Interior, State, and Transportation.

Economic growth impeded

The focus of the report is climate change impacts, risks, and adaptations occurring in the United States. The report contains supporting evidence from 16 national-level topic chapters (e.g., water, oceans, energy, and human health), 10 regional chapters, and two chapters that focus on societal responses to climate change. As noted, the president’s disbelief was directed at the findings of the report on economic impacts.

“Without substantial and sustained global mitigation and regional adaptation efforts, climate change is expected to cause growing losses to American infrastructure and property and impede the rate of economic growth over this century,” NCA4 states. More specifically:

“Regional economies and industries that depend on natural resources and favorable climate conditions, such as agriculture, tourism, and fisheries, are vulnerable to the growing impacts of climate change. Rising temperatures are projected to reduce the efficiency of power generation while increasing energy demands, resulting in higher electricity costs. The impacts of climate change beyond our borders are expected to increasingly affect our trade and economy, including import and export prices and U.S. businesses with overseas operations and supply chains. Some aspects of our economy may see slight near-term improvements in a modestly warmer world. However, the continued warming that is projected to occur without substantial and sustained reductions in global greenhouse gas emissions is expected to cause substantial net damage to the U.S. economy throughout this century, especially in the absence of increased adaptation efforts. With continued growth in emissions at historic rates, annual losses in some economic sectors are projected to reach hundreds of billions of dollars by the end of the century—more than the current gross domestic product (GDP) of many U.S. states.”

President expresses skepticism

In an interview with the Washington Post following the release of the report, Trump seemed to move the needle on his climate position closer to the denier side. “As to whether or not it’s man-made and whether or not the effects that you’re talking about are there, I don’t see it.”

When asked about the calamitous predictions, White House Press Secretary Sarah Huckabee Sanders questioned the factual basis of NCA4.

“This report is based on the most extreme modeled scenario, which contradicts long-established trends,” said Sanders. “Modeling the climate is an extremely complicated science that is never exact. The biggest thing we can do is make sure we have the cleanest air, the cleanest water, and the president is certainly doing that and leading on that front.”

This view repeats an earlier statement by White House spokeswoman Lindsay Walters, who noted that the assessment is still more the output of the Obama administration. The next assessment, due in 4 years, should include a broader range of scenarios, said Walters.

Regarding the report’s alleged contraction of long-established trends, Walters implied that the report predicts that greenhouse gas emissions will continue to increase without factoring in expected significant advances in new and innovative technologies to address the growth.