A Donald Trump administration cannot simply wish away inconvenient facts such as ongoing climate change and must accept scientific conclusions, the head of a top scientific organization said Thursday.

In an unusually frank and plainly worded commentary, the CEO of the American Association for the Advancement of Science said he was worried about federal funding for scientific research but also worried about the new political atmosphere after the November 8 election results.

An iceberg floats near the coast of West Antarctica on Oct. 27. Mario Tama / Getty Images

“This election is said to have been about rejecting the political establishment. We cannot let that mean rejecting established facts,” Rush Holt, a physicist and former Democratic representative for New Jersey, wrote in a commentary in his organization’s flagship journal, Science.

“We hope that President Trump will be more grounded in specific facts than was candidate Trump and pay more attention to the process of careful, open vetting of hypotheses and claims,” Holt added.

“We must make clear that an official cannot wish away what is known about climate change, gun violence, opioid addiction, fisheries depletion, or any other public issue illuminated by research.”

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Trump has repeatedly denied that people are responsible for climate change and sometimes goes so far as to deny it’s real. "I don't believe in climate change," he told CNN in September. Many Republicans in Congress also deny that climate change is real or caused by people.

“We hope that President Trump will be more grounded in specific facts than was candidate Trump."

Scientists worry a Republican-led government could pull the U.S. out of climate deals meant to help at least slow the decline into what many experts predict will be extreme weather and climate events as temperatures rise, ocean currents change and ice at both poles melts.

The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive. — Donald J. Trump (@realDonaldTrump) November 6, 2012

Holt points out that overwhelming scientific evidence is often dismissed as “theory” or as something that’s debated.

“Over recent decades, a disturbing trend in the U.S. government has been for ideological assertions to crowd out evidence,” he wrote.

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“This trend accelerated with this year’s campaign in which candidate Trump made statements that were unsubstantiated or contradicted by accepted scientific facts.”

He hopes Trump will hire good science advisers.

“Over recent decades, a disturbing trend in the U.S. government has been for ideological assertions to crowd out evidence."

“Will there be members in the new administration who are familiar with the practices and findings of scientific investigation? What are scientists to do? Certainly at the American Association for the Advancement of Science (AAAS), following a tradition nearly 170 years old, we will advocate forcefully that science be fully and positively integrated into public policy making,” Holt wrote.

Trump has mentioned the opioid crisis and has suggested he would like to work to help reduce overwhelming rates of addiction – something U.S. Surgeon-General Dr. Vivek Murthy highlighted in a report Thursday.

But he has suggested that laws limiting the display and carrying of firearms should be repealed. Public health experts have been pushing back against Republican-led efforts to limit research into the causes of gun violence. They say laws should be based on what scientific evidence shows about the effects of gun laws and gun possession, not on ideology.

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Congress has blocked federal health agencies from researching, or even paying for research, on gun violence since the 1990s.