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鲍辫诲补迟别:听This story was updated at聽10:55 a.m.聽to add comments from former Texas Gov. Rick Perry (R), the pick to lead the Energy Department.

The people poised to handle the federal government鈥檚 environmental portfolio appear to be trying to have it both ways on climate change: They are denying that it鈥檚 a 鈥渉oax,鈥� but they are questioning the ability to measure humanity鈥檚 contribution with 鈥減recision.鈥�

At first blush, the comments appear to be a departure from President-elect Donald Trump鈥檚 comment that climate change is a China-made fiction. In that way, Mr.聽Trump鈥檚 picks to head the Environmental Protection Agency, the Interior Department, Energy Department, and the State Department have sounded聽more aligned with the scientific consensus that humans are driving climate change.

But they鈥檙e not actually embracing that conclusion.

Instead, they鈥檙e pointing to models that show some variation on emissions, temperature, and sea-level rise projections and amplifying those small disagreements to discredit or sow doubt about the widely held conclusion that humans are driving emissions higher and raising temperatures, largely from burning fossil fuels.

To most climate scientists, the comments are 鈥渄eliberately misleading,鈥� says Susan Joy Hassol, director of Climate Communication. 聽

The nominees鈥� statements point to Republicans鈥� struggle to oppose climate science without dismissing it entirely, she and others say.聽

In 2014, GOP lawmakers attempted to deflect questions by saying, 鈥淚鈥檓 not a scientist.鈥� A year later, all but one Republican senator supported a resolution that climate change was 鈥渘ot a hoax,鈥� but they added that 鈥渃limate has always been changing.鈥�

This year鈥檚 congressional hearings are 鈥渁 return to the George W. Bush administration,鈥� which often delayed action on the grounds that the science was uncertain and ordered more studies on the issue, says Ms. Hassol.

鈥淭here is no disagreement among any legitimate scientist on that question,鈥� she adds.聽

Points of confusion

Scott Pruitt, the Republican Oklahoma attorney general whom Trump tapped to lead the EPA, said in his Wednesday confirmation hearing that climate change is 鈥渃aused by human activity in some manner. I believe the ability to measure with precision is subject to more debate.鈥�

That came one day after Interior nominee Rep. Ryan Zinke (R) of Montana, told a Senate panel during his confirmation hearing that the 鈥渃limate is changing, man is influencing it 鈥� I think where there is debate" is how much.

And last week, former ExxonMobil CEO Rex Tillerson, the top choice to lead the State Department and United States climate diplomacy, said 鈥渨e cannot predict with precision鈥� the effects of climate change and that the science behind connectivity to extreme weather events is 鈥渘ot conclusive.鈥� He added, however, that 鈥渄oesn鈥檛 mean that we should do nothing."

Former Republican Texas Gov. Rick Perry, vying for the Energy Department's top spot, weighed in during his Thursday confirmation hearing that,聽鈥淚 believe the climate is changing" and that "some of it is naturally occurring, some of it is caused by man-made activity.鈥�

Admittedly, climate models are complex and can differ on many fine points around timing and degree of changes. And since they are predicting well into the future, they are inherently imprecise.

That can give rise to confusion among the public, scientists say.

鈥淢odels can give rather different answers because they were intended for different purposes. It does mean that it takes experts to properly interpret results, and casual observers and politicians can easily be led astray,鈥� says Kevin Trenberth, a senior climate scientist at the National Center for Atmospheric Research in Boulder, Colo., in an email.

But emphasizing those differences can be a red herring.

鈥淭his line tends to ignore the certainties that climate change is happening and it is caused by humans, and we argue about details,鈥� says Dr. Trenberth. 鈥淚t can be used as a mask to say we will do nothing.鈥�

Scientists, Trenberth notes, often emphasize the uncertainties 鈥� like the effect climate change will have on precipitation 鈥� since that鈥檚 where more research and improved modeling is needed. But for policymakers to zero in on those uncertainties as a defense of inaction can be dangerous.

Mr. Pruitt, the EPA nominee, did commit to regulating carbon dioxide emissions if confirmed. But his questioning of how much humans contribute to a warmer planet may translate into a light regulatory touch.

Senate Democrats haven鈥檛 elicited particularly detailed views from Trump鈥檚 Cabinet picks during the hearings. What the candidates have offered feeds misinformation that hinders action, Hassol argues.

鈥淎t this point confusion may be as dangerous as contrarianism and delay as insidious as denial,鈥� she says.

Shifts in public opinion

The hearings come at a time when the World Meteorological Organization confirmed that 2016 was the hottest year on record 鈥� the third year in a row that global temperatures have set a record.

Moreover, Americans are increasingly concerned about the issue, according to a survey released Wednesday.

While climate change is still a polarizing topic, the survey by the Yale Program on Climate Change Communication and the George Mason University Center for Climate Change Communication shows a record number of Americans 鈥� 19 percent 鈥� say they are 鈥渧ery worried鈥� about global warming. Some 61 percent are 鈥渟omewhat鈥� or 鈥渧ery鈥� worried.

Seven in 10 Americans believe global warming is happening (compared with 13 percent who say it is not happening), and the proportion of Americans who are either 鈥渆xtremely鈥� or 鈥渧ery sure鈥� global warming is happening is 45 percent, the highest proportion since the survey began in 2008.

Says聽Anthony Leiserowitz, director of the Yale program:聽The polarization around climate change 鈥渋s beginning to shift.鈥澛�