On March 28, 2012, 49 former NASA astronauts, scientists, engineers, and administrators sent a letter to NASA administrator Charles Bolden Jr. The letter requested that NASA in general and the Goddard Institute for Space Studies (GISS) in particular stop publishing the scientific conclusions about the human-driven causes of global climate disruption. The letter was filled with no less than six serious errors regarding the science, data, and facts of climate science. The errors, in turn, exposed that the signers had confused their fame and/or their expertise in unrelated fields with expertise in climate science. And in response, NASA’s chief scientist politely suggested that the letter’s authors and signers should publish any contrary hypotheses and data in peer-reviewed scientific journals instead of trying to censor the publication of scientific conclusions from NASA climate scientists.

The first error

The first error in the letter is that the authors and signers deny that “empirical data” shows “man-made carbon dioxide” is having an impact on global climate disruption:

We believe the claims by NASA and GISS that man-made carbon dioxide is having a catastrophic impact on global climate change are not substantiated, especially when considering thousands of years of empirical data.

In reality, “thousands of years of empirical data” do substantiate the claim that man-made carbon dioxide (CO 2 ) is driving global climate change. Michael Mann, Ray Bradley, and Malcolm Hughes demonstrated that modern warming of the Northern Hemisphere was very likely greater than at any period in the last 2000 years first in 1999, then again in 2008, and it’s been verified repeatedly by independent researchers Wahl and Ammann in 2007, Huang et al in 2000, Smith et al in 2006, and others.

Not only have multiple independent researchers demonstrated that global temperatures are likely greater than at any period in the last 2000 years, but the data used by researchers are all independent too. Sources as varied as marine sediments, corals, tree rings, stalagmites, boreholes, the length of glacial tongues, ice cores, and lake sediments all independently confirm that modern global temperatures are anomalously high. Independent researchers using independent data and methodologies to reproduce the each other’s results is the ideal for how to conduct good science.

Similarly, scientists have analyzed the effects of CO 2 on the balance of energy in the Earth’s climate system and found that CO 2 must be having a major effect. If it wasn’t a major driver of climate disruption, several well established physical laws would have to be wrong (conservation of energy, for one). For more information on this, S&R has some posts on this subject, both in reference to the Earth’s carbon cycle and Venus’ greenhouse effect. An even better high level overview is available from Skeptical Science.

The second error

The second error is that only a few climate scientists have declared that they deny the science underlying human-driven climate disruption, not the “hundreds” the letter claims. While the letter doesn’t provide any support for this allegation (yet another serious error), this is likely a reference to Oklahoma Senator James Inhofe’s December 2008 “Senate Minority Report” of about a supposed 700 scientists who deny human-driven climate disruption. The Center for Inquiry performed a detailed analysis of Inhofe’s list and discovered that:

Slightly fewer than 10 percent could be identified as climate scientists. [about 70]

Approximately 15 percent published in the recognizable refereed literature on subjects related to climate science. [about 135]

Approximately 80 percent clearly had no refereed publication record on climate science at all. [about 560]

Approximately 4 percent appeared to favor the current IPCC-2007 consensus and should not have been on the list. [about 28 – notes added by editor]

Inhofe’s prior lists have been found to be similarly defective. Furthermore, recent studies (Doran 2009, Anderegg 2010, S. Robert Lichter, for STATS in 2008, and a Pew survey of AAAS member scientists from 2009) found that scientists in general and climate scientists in particular overwhelmingly agree that human activity is disrupting the global climate.

The third error

The third error is the letter’s reference to “tens of thousands of other scientists” who supposedly deny climate disruption. Unlike the vagueness of the second error, this reference can only mean one list, namely the list of approximately 31,000 alleged scientists collected by the Oregon Institute of Science and Medicine. While S&R debunked this list in detail three years ago, it’s worthwhile to reiterate a few key points from the original post:

The OISM’s criteria are so broad that nearly anyone with a Bachelor of Science degree is eligible to call him or herself a “scientist.” It doesn’t matter whether you work in a scientific field, whether you’re an engineer instead of a scientist, or even if you’re a stay-at-home Mom or Dad with an unused degree – if you’ve got a BS degree in one of a large number of fields, you’re a “scientist.”

Even if we assume that a mathematician, nuclear engineer, or veterinarian should qualify as a “scientist,” using the OISM’s own criteria produces over 10.7 million “scientists” who have graduated from US universities since 1970. The OISM’s 31,478 so-called scientists represents 0.3%, or one out of every 340 scientists. That’s an insignificant minority.

The OISM list contains only 152 atmospheric scientists, or 2.1% of the American Geophysical Union’s members who are atmospheric scientists.

The OISM list contains only 22 hydrologists, or 0.4% of the AGU’s hydrology group membership.

The OISM list contains only 341 meteorologists, about 2.4% of the American Meteorological Society’s membership.

The OISM’s list of names would be laughable if people didn’t refer to it in a naive or dishonest attempt to deny the remarkable agreement among climate scientists (and actual scientists in general) about the human-driven nature of climate disruption.

Coincidentally, the 49 former employees who signed the letter represent about 0.3% of the current headcount at NASA, never mind the between 54,000 and 102,000 people NASA has employed since it was created in 1958. As with the OISM list, 0.3% is an insignificant minority.

The fourth error (updated)

The fourth error is that the letter twice uses the subjective, unscientific term “catastrophic” in reference to climate disruption.

Scientists don’t use the term “catastrophic,” and there’s a good reason for that: try to define exactly what you mean by “catastrophic” in an objective way. Whether something is a catastrophe or not is a matter of opinion, and no scientist involved in climate would ever use such a subjective term to describe something that is objectively scientific. It’s probably fair to say that most scientists would view the end of all life on Earth as a catastrophe, but what about sea level rise that drives millions of people out of their low-lying homes? That would be a catastrophe for the resulting climate refugees, but is it “catastrophic” in a scientifically objective way?

The term “catastrophic” is used almost exclusively by people who oppose adaptation and/or mitigation of the projected outcomes of human-driven climate disruption, and it’s used in an attempt to make climate scientists appear biased or extreme. Actual climate scientists, on the other hand, simply describe what they project will occur in an objective manner, just as unbiased scientists should.

The fifth error

The fifth error is that the letter claims that there hasn’t been a “thorough study” of “natural climate drivers.”

[W]e feel that NASA’s advocacy of an extreme position, prior to a thorough study of the possible overwhelming impact of natural climate drivers is inappropriate.

Natural factors in climate change – solar variability, Milankovic cycles, volcanism, El Nino, even cosmic rays – have been investigated very thoroughly, and none of the natural factors are capable of generating the observed disruptions in the global climate. The impacts of natural drivers on climate disruption have been investigated repeatedly and in detail, as the two figures (from the Skeptical Science website) below show.



Human vs. natural percent contributions to climate disruption over the past 50-65 years according to various peer-reviewed studies.

That’s 13 different ways we know that human activity is driving global climate disruption, and six major peer-reviewed scientific papers that describe just how much is driven by human activity vs. natural factors.

The letter’s authors and signers seem to want NASA to censor the publication of scientific conclusions about human-driven climate disruption until scientists are 100% certain the conclusions are correct. This is more than just unrealistic – it’s impossible. It’s impossible to guarantee anything in science or engineering to 100% certainty, and as former employees of NASA, every one of the authors and signers knows it instinctively: Apollo 1, Apollo 13, Challenger, and Columbia, just for starters.

Anyone who works for NASA – or, like I do, works for a NASA subcontractor – lives and breathes the fact that nothing can be guaranteed to 100%. Any former NASA employee who has forgotten this should be ashamed of themselves.

The sixth error

The sixth error is that the letter claims NASA is making “unproven” and “unsupported” remarks about climate disruption and asks NASA to not make any more. The analysis of the five prior errors shows just how wrong this really is – there’s a massive amount of proof and support that human activity, namely burning fossil fuels and agriculture, are the primary driver of climate disruption. But in case there’s any question of that, here’s a link to Skeptical Science’s list of climate myths, with detailed rebuttals supported by referenced peer-reviewed scientific papers in reputable journals: Taxonomy of Climate Myths.

And in case that’s not enough, we can recount a few of the established physical laws and properties of CO 2 that would all be wrong if human activity wasn’t the dominant driver of climate disruption today:

Conservation of energy

Conservation of mass

Quantum mechanics

Vibrational modes of CO 2

Radiative transfer

Isotope ratio science for carbon-12, carbon-13, and carbon-14

Radioisotopic dating

et al

And that’s just a short list. The man-made nature of climate disruption is based on so many well established, basic physical principles that it can’t be rationally disputed without shattering large portions of modern science (physics, chemistry, biology, and geology just for starters) and ignoring most of the modern technology (GPS, IR cameras, heat-seeking missiles, weather satellites, etc.) that was successfully designed and built using that science.

As serious as all those errors are, each and every one of them can be corrected with education and experience. Of greater concern is the underlying causes of the errors, namely two related shortcomings on the part of all the letter’s authors and signers – the belief that their fame or their expertise in other fields automatically granted them authority to comment on climate science.



Mission Operations Control Room, April 13, 1970 (Apollo 13, just prior

to the explosion) Mission Operations Control Room, April 13, 1970 (Apollo 13, just priorto the explosion)

Fame is no substitute for expertise

Many of the 49 former NASA employees are famous for one reason or another. I counted seven who were astronauts. Gerald D. Griffin and Joe Kerwin were both part of the team that got Apollo 13 home safe, and Griffin was also the Director of the Johnson Space Center. Christopher C. Kraft developed NASA’s Mission Control concept and also served as the Director of Johnson Space Center.

But while fame occasionally comes as a result of expertise, expertise is never a result of fame. If you’re not sure about this, ask yourself the following question: would you want Paris Hilton landing your commercial airliner? How confident would you be if NASA installed Snookie in Mission Control? Would you trust your retirement to George Clooney?

In reality, fame grants one thing – attention. When a celebrity speaks, people listen, even if people shouldn’t. In fact, the organizers of this letter (most likely Harrison Schmitt and/or Walter Cunningham) relied on their fame as astronauts to get Fox News, Marc Morano, the Huffington Post, Anthony Watts, the Houston Chronicle and others, to report on and repeat verbatim many of the letter’s naive or dishonest statements regarding climate.

Albert Einstein was the expert in relativity, and he earned his fame partly as a result of that expertise. But Einstein’s fame merely meant that people listened when he spoke, not that he was an expert on every subject on which he spoke. [See Ed. note below] In fact, he famously denied some of the weirder implications of quantum mechanics that have since been observed. Nikola Tesla claimed that relativity was something whose “exponents are brilliant men but they are metaphysicists rather than scientists,” yet relativity has also been demonstrated. Lord Kelvin, developer of the concept of absolute temperature, denied scientific data and theories that demonstrated that the Earth’s age was older than 20-40 million years. Harold Jeffreys, one of the geologists who proved that the Earth’s outer core was molten, rejected plate tectonics entirely.

Those four scientists were justifiably famous, and all were brilliant scientists in their areas. But that doesn’t mean that they didn’t make mistakes, and it doesn’t mean that they always accepted the latest and best science. Each of them denied scientific theories that have since become mainstream scientific thought.

Similarly, many of the former NASA employees who signed the letter earned their fame, but they’re no more experts in climate science than Einstein was in quantum mechanics or Tesla was in relativity. The large number of errors in such a short letter (227 words in four paragraphs) demonstrates that the former NASA employees do not understand climate disruption and no amount of fame, however well earned, can change that fact.

Expertise is non-transferrable

But even more important than the issue of fame is the fact that expertise in one field does not make anyone an expert in a different field, even one that’s closely related. I’m an expert in designing electronics to convert light and temperatures into digital data that a computer can use, but that doesn’t make me an expert at designing the computer itself, the networking equipment used to move that data around, or the antennas used to transmit it from a satellite to the ground. The skills I have that are broadly applicable to all of electrical engineering give me a leg up in designing computers, networking equipment, and antennas, but only years of experience could make me an actual expert.

Given my electrical engineering expertise doesn’t make me an expert in every field of electrical engineering, I certainly can’t claim that my electrical engineering expertise makes me an expert in climate science. If I want to claim expertise in climate science, I first have to prove that I have somehow acquired the knowledge and skills of a climate expert.

None of the letter’s authors or signers have any expertise in a climate-related field, and they’ve offered no proof that they have independently acquired the necessary expertise. Expertise in the effects of high levels of carbon dioxide on astronauts doesn’t make one an expert on CO 2 ‘s effect on ecosystems. Expertise in lunar geology doesn’t make one an expert in geochemical sequestration of atmospheric carbon dioxide. Expertise in heat transfer through space shuttle heat tiles doesn’t make one an expert in heat transfer between the Earth’s surface and the atmosphere. Even expertise in weather forecasting doesn’t make the forecaster an expert on climate.

No amount of expertise on one subject can magically bestow expertise on any other subject. Expertise must be earned through dedicated effort day in and day out, over the course of years. And there’s no evidence that any of the letter’s authors and signers have earned any climate expertise.

Think about this for a moment. If you were in charge of the safety of the space shuttle upon re-entry, who would you listen to first – an electrical engineer like me, or an expert in the shuttle’s ceramic heat tiles? Unless I could prove that I knew what I was talking about, you’d correctly ignore my advice and listen to the actual expert.

So why would you listen to an expert on heat tiles – or medicine, or lunar geology – when he’s writing a letter about climate science? Especially a letter that is packed full of obvious, naive or dishonest errors.

NASA’s response to the letter

NASA’s chief scientist, Waleed Abdalati, published a short response to the letter. In it, Abdalati wrote that “NASA does not draw conclusions and issue ‘claims’ about research findings” that NASA researchers conduct. Instead, NASA “strongly encourage[s] scientists to communicate” the results of their research “after these studies have met the appropriate standards of scientific peer review.” Abdalati also said

If the authors of this letter disagree with specific scientific conclusions made public by NASA scientists, we encourage them to join the debate in the scientific literature or public forums rather than restrict any discourse.

In other words, put up or shut up. Clearly NASA doesn’t have the same concerns about the scientific conclusions of their scientists that these former NASA employees do.

So why did the 49 former NASA employees sign this letter filled with naive or dishonest claims against NASA and the researchers at GISS? Without asking each and every signer, it’s impossible to say beyond guesswork. Perhaps the signers were misled by the authors. Perhaps they’re concerned about budget cuts gutting manned space flight more than it already has been (all the signers are from Johnson Space Center in Houston, where Mission Control is located). Perhaps they’re merely ignorant of how much elementary science would need to be wrong in order for human-driven climate disruption to be incorrect.

Or perhaps it’s as simple as they said in the letter: “At risk is damage to the exemplary reputation of NASA, NASA’s current or former scientists and employees….” Abdalati’s excellent response makes it clear that NASA’s exemplary reputation is intact, as is the reputation of NASA’s current employees.

Unfortunately, the same cannot be said of the reputations of these 49 former NASA astronauts, scientists, engineers, and administrators.

[Ed. Note (4/26/12): A quantum mechanics researcher pointed out to me in an email that my point about Einstein isn’t quite accurate – Einstein was one of the many co-developers of quantum mechanics, so he was an expert in the subject, even if did reject quantum entanglement.]

Other voices of sanity on the letter:

Additional Image Credits:

NASA

NASA

NASA/Bill Ingalls