The U.S. Department of Agriculture building  in Washington (Jonathan Newton / The Washington Post)

This story has been updated.

President Trump on Wednesday nominated Sam Clovis, a former college professor and talk radio host who has challenged the scientific consensus that human activity has been the primary driver of climate change, to serve in the Agriculture Department’s top scientific post.

“Dr. Clovis was one of the first people through the door at USDA in January and has become a trusted advisor and steady hand as we continue to work for the people of agriculture,” Agriculture Secretary Sonny Perdue said in a statement Wednesday evening. “He looks at every problem with a critical eye, relying on sound science and data, and will be the facilitator and integrator we need. Dr. Clovis has served this nation proudly since he was a very young man, and I am happy he is continuing to serve.”

Clovis, whose expected nomination has been previously reported by The Washington Post and several other outlets, is a former economics professor at Morningside College in Sioux City, Iowa, who served as one of Trump’s first campaign policy advisers. In a 2014 interview with Iowa Public Radio, he said he was “extremely skeptical” about climate change and added that “a lot of the science is junk science.”

“It’s not proven; I don’t think there’s any substantive information available to me that doesn’t raise as many questions as it does answers,” Clovis said in the interview. “So I’m a skeptic.”

This position represents a departure from the scientific consensus. In its most recent report, the U.N. Intergovernmental Panel on Climate Change concluded that it is “extremely likely” that, since the 1950s, humans and their greenhouse gas emissions have been the “dominant cause” of the planet’s warming trend.

Neither USDA nor Clovis responded to inquiries earlier this week about the prospect of his appointment, and his views on climate science.

Clovis — who started at USDA as a senior White House adviser just after Trump was inaugurated  — possesses a B.S. in political science, an MBA degree and a doctorate in public administration, according to the White House. The post for which he is being nominated, the Agriculture Department’s undersecretary for research, education and economics, has traditionally been occupied by a string of individuals with advanced degrees in science or medicine.

The overall portfolio that would be managed by Clovis, if he is confirmed by the Senate, is worth about $ 3 billion, with $ 2 billion devoted to research and $ 1 billion to education, according to Catherine Woteki, a nutrition scientist who held the job before Clovis. The person holding the position administers the Agricultural Research Service, the Economic Research Service, the National Agricultural Statistics Service, and the National Institute of Food and Agriculture.

The undersecretary also serves as the USDA’s chief scientist. The 2008 farm bill specifies that appointees to the post should be chosen “from among distinguished scientists with specialized training or significant experience in agricultural research, education, and economics.” The measure noted that the job is “responsible for the coordination of the research, education, and extension activities of the Department.”

“There’s a huge amount of science that goes into the setting up of the programs, implementation of various policies, and the chief scientist role is to coordinate those policies across the entire department and to represent agricultural science in the decisionmaking that goes on with other departments and is coordinated with the white house science office,” said Woteki.

Furthermore, the Agriculture Department’s chief scientist is also tasked with administering its policies to ensure “scientific integrity” in the department, which means examining whether any abuses or misuses of science may have occurred in the agency.

Climate change is a major issue in the agricultural sector, as shifts in both temperatures and precipitation have a major impact on food production. Agricultural operations also rank as a major emitter of greenhouse gases linked to climate change, because of methane emissions from livestock and carbon emissions from heavy farm equipment.

Under the Obama administration the Agriculture Department had elevated the issue of climate change, seeking to curb agricultural emissions as well as help farmers adapt to changing conditions by creating regional “climate hubs” across the United States. Then-Agriculture Secretary Tom Vilsack sought to enlist farmers, ranchers and forest owners in the effort to capture and store carbon nationwide.

Since Trump took office, the agency has shifted the description of some of these efforts. On Wednesday, for example, the department’s National Institute of Food and Agriculture announced nine grants totaling more than $8 million “to study and develop new approaches for the agriculture sector to adapt to and mitigate the effects of changing environmental conditions.” But the same press release noted that four of them were directed toward “climate outreach and extension” and another five were focused on “climate and land use.”

Clovis, an Iowa political activist who ran unsuccessfully for the U.S. Senate in 2014, has emphasized his military and foreign policy experience in the past. During the 2016 presidential race Clovis advised Trump on Russia and other matters.

In the 2014 Iowa Public Radio Interview, Clovis outlined his credentials for public service.

“I think that if you look at my experience … 25 years in the military, and the various jobs and opportunities I had while serving the nation, my experience as a business man, and my academic preparation … my experience in a variety of other fields, including homeland security, foreign policy, national security policy, creating jobs and all those things,” Clovis said.

The White House announcement of his nomination emphasizes his military background, noting, “After graduating from the [U.S. Air Force] Academy, Mr. Clovis spent 25 years serving in the Air Force. He retired as the Inspector General of the North American Aerospace Defense Command  and the United States Space Command and was a command pilot.”

The position for which Clovis has been appointed ranks among “the most critical” science and technology roles in the federal government, according to a 2008 report by the National Academy of Sciences. The position requires Senate confirmation.

The Trump administration has been slow to fill top Senate-confirmed science jobs — only 10 out of 45 across the government had a nominee prior to the Clovis appointment, according to a Post analysis that is based on that same NAS report. Clovis makes 11.