Unlike past Nasa administrators, Trump nominee Jim Bridenstine doesn’t have a scientific background. He’s a Republican Congressman from Oklahoma and former Navy pilot. He also has a history of denying basic climate science. That’s concerning because Nasa does some of the world’s best climate science research, and Bridenstine previously introduced legislation that would eliminate Earth science from Nasa’s mission statement.

At his Senate hearing last week, Bridenstine tried to remake his image. He said that his previous science-denying, politically polarizing comments came with the job of being a Republican congressman, and that as Nasa administrator he would be apolitical. A kinder, gentler Bridenstine. But while he softened his climate science denial, his proclaimed new views remain in line with the rest of the harshly anti-science Trump administration. That’s very troubling.

A gentler form of climate science denial

The standard Trump administration position on climate change, held by administration officials like EPA Administrator Scott Priutt and Energy Secretary Rick Perry, is that humans are contributing to global warming, but we don’t know how much. Bridenstine repeated that position in a tense exchange with Senator Brian Schatz (D-HI).

Facebook Twitter Pinterest Exchange between Senator Brian Schatz (D-HI) and Jim Bridenstine in the latter’s confirmation hearing to become Nasa administrator.

To be clear, the Trump administration stance is unequivocally wrong. The last IPCC report concluded with 95% confidence that humans are the primary cause of global warming since 1950, and its best estimate was that humans are responsible for all of the global warming during that time. That’s also the conclusion of the just-released US National Climate Assessment Report, which states:

Many lines of evidence demonstrate that it is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century. Over the last century, there are no convincing alternative explanations supported by the extent of the observational evidence. Solar output changes and internal natural variability can only contribute marginally to the observed changes in climate over the last century, and we find no convincing evidence for natural cycles in the observational record that could explain the observed changes in climate. (Very high confidence)

As many scientists pointed out, this is not new information.

Robert Brulle (@RBrulle) New report, same as the old report. Climate change projections remain unchanged. pic.twitter.com/ZdY5pecQfL

But it nevertheless directly contradicts Bridenstine’s comments. In response to Sen. Schatz’s question about the expert consensus that humans are the primary cause of global warming, Bridenstine said:

It’s going to depend on a lot of factors and we’re still learning more about that every day. In some years you could say absolutely, in other years, during sun cycles and other things, there are other contributing factors that would have maybe more of an impact.

Aside from being wrong about the sun’s influence on recent climate change (which if anything is in the direction of cooling), Bridenstine also displayed a lack of understanding of what climate change is. Climate changes are defined on timescales of several decades, not year-to-year variations.

As Senator Schatz noted, we shouldn’t fault Bridenstine for his lack of understanding of basic climate science. But we should fault him for failing to defer to the expert consensus on a subject about which he lacks basic understanding. Bridenstine claimed to believe that the expert consensus is merely that humans are causing some global warming. That’s incorrect, and in fact Nasa climate scientists published a paper in 2010 entitled Atmospheric CO 2 : Principal Control Knob Governing Earth’s Temperature. And Nasa itself is quite clear about the expert consensus.

NASA Climate (@NASAClimate) Happy Pi Day! What's the 97% math all about? Learn here: http://t.co/BZ2BQ0CVkp #PiDay #ClimateChange pic.twitter.com/F5dr1xoUGR

The Trump playbook: why Bridenstine triggers alarm bells

Bridenstine’s testimony was that of a completely different person than Rep. Jim Bridenstine (R-OK). He said that he would be an apolitical administrator; he accepted at least some very basic climate science; said he would support Nasa’s climate science research; would no longer support discrimination of LBGT Americans; etc.

However, in their congressional hearings, Scott Pruitt and Rick Perry also accepted the century-old science telling us that humans contribute to global warming. In the time since the Senate confirmed their appointments, the Trump administration has begun the processes to withdraw the US from the international Paris climate agreement and repeal the Clean Power Plan. Climate change has been deleted from government websites, the EPA is barring many scientists from serving on its science advisory boards, EPA climate scientists have been censored, and the Department of Energy is perversely trying to bail out the failing coal industry with taxpayer subsidies. Oh, and one of Pruitt’s new EPA science advisors thinks America’s air is too clean.

This has been the most anti-science administration in American history, and it began with Trump’s nominees taking the same watered-down climate science denial position that Bridenstine took in his hearing. The Trump administration’s actions, combined with Bridenstine’s own history of climate science denial and opposition to Nasa’s climate science research, should trigger alarm bells for the senators voting on his confirmation.

Climate science denial is the GOP norm

However, the congressional hearing showed why we can expect most Republican senators to vote to confirm Bridenstine. The hearing was held by the Senate Commerce, Science, & Transportation Committee, whose members one would hope are relatively scientifically literate. Sadly, much like its sister House (Anti-)Science Committee, that’s not the case.

For example, Senator James ‘global warming is the greatest hoax’ Inhofe (R-OK) sits on the senate science committee. During the hearing, Inhofe proclaimed “This 97 percent [expert climate consensus] stuff has been debunked completely and everybody knows that.” That claim is of course entirely false. Senator Mike Lee (R-UT) said, “It’s my understanding that it’s not even the position of Nasa at this point that there is a consensus that [climate change is primarily caused by human activity].” Senator Lee’s understanding is wrong. Nasa has a whole page on its website devoted to explaining why “most climate scientists agree the main cause of the current global warming trend is human expansion of the ‘greenhouse effect.’”

Senator Roger Wicker (R-MS) had the most ant-science statement of the hearing, criticizing “the audacity to think that we are so important that we are causing that climate change.” Wicker didn’t deny the existence of the scientific consensus, but dismissed it because consensus “hasn’t always been right,” inappropriately citing Galileo as an example.

It’s almost 2018 and these are the comments being made about climate change by the Republican members of the senate science committee. Until he had an apparently sudden change of heart coinciding with his nomination to run Nasa, Bridenstine shared those climate denial beliefs, and like the rest of Trump’s cabinet, he still doesn’t accept the overwhelming scientific consensus.

In his testimony, Bridenstine promised not to interfere with Nasa’s climate science research, but given the Trump administration’s war on climate science and Bridenstine’s alignment with that political agenda in the very recent past, it’s difficult to take him at his word. Democrats on the Science Committee expressed deep skepticism of Bridenstine’s sudden change of heart, and given the anti-climate science behavior of the rest of the Trump administration, that skepticism is wholly justified.

If the Republican majority confirms Bridenstine, we can only hope he is sincere in changing his ways and leaving behind the politicized climate science denial exemplified by his Republican congressional colleagues.