President-elect Trump's nominee for secretary of the interior Rep. Ryan Zinke (R-Mont.) testified before the Senate Committee on Energy and Natural Resources, Jan. 17. Here are the key moments from that hearing. (Sarah Parnass/The Washington Post)

Sally Jewell, President Obama’s secretary of the Interior, thought the warming of the planet was a big deal. From the Florida Everglades to the coast of the Chukchi Sea in Arctic Alaska, she took trips during her tenure designed to highlight how a changing climate is already impacting the United States.

In contrast, Ryan Zinke, the Montana congressman that Donald Trump has named to succeed Jewell, is tougher to read on this matter. As our own Chelsea Harvey has documented, Zinke appears to have changed his stance on the subject of human-caused climate change. He seems to have believed in it before he didn’t — something his Democratic opponent in the 2014 congressional election, John Lewis, sought to highlight.

This is now one of the key questions unfolding at Zinke’s confirmation hearing Tuesday before the Senate Energy and Natural Resources Committee. “The issue of climate change is in fact very important for issues the Department of the Interior deals with. Is President-elect Trump right? Is climate change a hoax?” asked Sen. Bernie Sanders (I-Vt.) in the hearing. It was one of several climate change questions that Zinke received.

Zinke responded that the climate is changing and that is “indisputable,” remarking in particular on the retreat of glaciers in Montana’s Glacier National Park. He also said that humans are an “influence” on climate change, but quickly added, “I think where there’s debate on it is what that influence is, what can we do about it.”

Zinke also noted that the U.S. Geological Survey is part of the Interior Department and “we have great scientists there. I am not a climate scientist expert but I can tell you I will become a lot more familiar with it and it will be based on objective science. I do not believe it is a hoax.”

Contrary to Zinke’s assertion about a “debate” regarding the role of humans in climate change, scientists have said that it is “extremely likely” that “human influence has been the dominant cause of the observed warming since the mid-20th century.”

Later in the hearing, Democratic Senator Al Franken of Minnesota also asked Zinke about climate change, and pressed him when Zinke said he was “not an expert in this field.”

“That to me is a cop-out,” Franken said. “I’m not a doctor but I have to make healthcare decisions.”

Zinke responded, “And I too sit on the Natural Resources Committee and I have went through hundreds of hours of testimony on all topics. There is no model today that can predict tomorrow.”

Climate change models don’t “predict” the future precisely but they project the large scale influence of increasing greenhouse gases on the climate system, based on basic physical equations that are understood to govern the way the atmosphere and the oceans work. While scientists know models aren’t perfect, they generally argue that they’re useful tools for understanding how the climate system works and the role that different components (like, human greenhouse gas emissions) play in driving the overall temperature.

Still, Zinke’s overall approach here seems consistent with how other Trump nominees have addressed this tough question. Last week, State Department nominee Rex Tillerson and CIA nominee Mike Pompeo both answered climate change questions at their confirmation hearings by perhaps minimizing the scale of the problem, but not by denying its reality outright.

It remains to be seen what other nominees — specifically Environment Protection Agency nominee Scott Pruitt and Energy Department nominee Rick Perry — will say at their own confirmation hearings this week.

Many of the decisions that Zinke will make, as head of the Interior Department, will have climate change implications. Most important, the department manages lands and offshore areas that are attractive for coal, oil, and gas exploitation — and in general, the Obama administration has slowed down mining and drilling in these areas, while also promoting the development of renewable energy on public lands.

Concern about climate change was central to these moves. But if you aren’t concerned about the issue, then it becomes more justifiable to continue withdrawing fossil fuels from the ground, fuels destined to be burned.

That’s something Zinke defended Tuesday. He favored both coal mining and also renewable energy installations on public lands.

“I think that’s the better solution going forward, is ‘all of the above’ energy,” Zinke said.