by Judith Curry

My analysis of EPA Administrator Scott Pruitt’s recent statements on climate change, and the response to his statements.

Last week, there was a controversial interview of Scott Pruitt on CNBC. A sampling of the headlines reporting on his interview:

New Yorker: Scott Pruitt rejects climate change reality. A relatively thorough summary of the interview with Scott Pruitt.

Washington Post: On climate change, Scott Pruitt causes an uproar — and contradicts the EPA’s own website.

CNBC: Scott Pruitt’s climate denial is dangerous and out of step.

Guardian: EPA head Scott Pruitt denies that carbon dioxide causes global warming. Subtitle: Trump adviser shocks scientists and environmental advocates with statement that negates EPA policy and ‘overwhelmingly clear’ evidence on climate change

David Robert at Vox: Scott Pruitt denies basic climate science. But most of the outrage is missing the point. Subtitle: It’s not about Pruitt and it’s not about facts. Excerpt: The right’s refusal to accept the authority of climate science is of a piece with its rejection of mainstream media, academia, and government, the shared institutions and norms that bind us together and contain our political disputes.

A number of scientists have responded in various venues regarding their opinion on Scott Pruitt’s statements. Here I include the ‘official’ statement from the AGU:

AGU Responds to Statements from EPA Administrator Scott Pruitt on Climate Change. Excerpt: The position statement of the American Geophysical Union regarding climate change leaves no doubt that increasing atmospheric concentrations of carbon dioxide resulting from human activity is the dominant source of climate change during the last several decades.

You may recall my concerns about the AGU policy statement on climate change [link]

What Scott Pruitt actually said

Listen to what Scott Pruitt actually said on CNBC and then compare it to the portrayal in the media. Here is the key text:

I think that measuring with precision human activity on the climate is something very challenging to do and there’s tremendous disagreement about the degree of impact, so no, I would not agree that it’s a primary contributor to the global warming that we see. But we don’t know that yet. We need to continue the debate and continue the review and the analysis.

Can you square what Pruitt actually said with the distorted quotes and headlines about this? I can’t.

I think that these two statements made by Pruitt are absolutely correct:

I think that measuring with precision human activity on the climate is something very challenging to do and there’s tremendous disagreement about the degree of impact



We need to continue the debate and continue the review and the analysis.

The other two statements give slightly conflicting messages:

I would not agree that it’s a primary contributor to the global warming that we see. But we don’t know that yet.

The main statement of controversy is:

I would not agree that it’s a primary contributor to the global warming that we see.

You can interpret this in two ways:

1.Pruitt is denying that CO2 is a primary contributor to recent global warming

OR

2.Pruitt is saying that he does not accept as a ‘fact’ that CO2 is a primary contributor because we simply don’t know.

Since his subsequent statement is “But we don’t know that yet”, #2 is obviously the correct interpretation.

I think he is saying that he is not convinced that we know with certainty that humans have caused 100% of the recent warming (which is what some climate modelers are saying, see recent tweets from Gavin Schmidt), or that humans have caused ‘more than half’ of the recent warming (which was the conclusion from the IPCC AR5.

JC reflections

If I am interpreting Pruitt’s statements correctly, I do not find anything to disagree with in what he said: we don’t know how much of recent warming can be attributed to humans. In my opinion, this is correct and is a healthy position for both the science and policy debates.

Exactly what the Trump administration intends to do regarding funding climate science, energy policy and the Paris climate agreement presumably remain as subjects of debate within the administration. Looking at every little leak and quote out of context as a rationale for hysteria simply isn’t rational or useful.

The most interest reaction to all this is David Robert’s vox article:

The right’s refusal to accept the authority of climate science is of a piece with its rejection of mainstream media, academia, and government, the shared institutions and norms that bind us together and contain our political disputes.

The ‘problem’: a change of administration and party after 8 years, mainstream media no longer has a lock on the media’s message (given all of the new news sources on the internet), academia’s profoundly liberal bias is being challenged, and the consensus that has been negotiated and enforced by certain elite scientists is being challenged.

Three cheers for democracy, the internet and the scientific process.