Another week, another global warming denialist spasm. The latest one suffusing national headlines is from a group of former NASA employees (full text here) directed to NASA’s Public Administrator, Charles Bolden. The letter is signed by 49 ex-NASA scientists who claim that man-made climate change is unsubstantiated and supporting it could tarnish the future reputation of NASA.
The letter itself is terse – just three short paragraphs – and fully devoid of any substance, leaving the public to figure out their collective motivations. Much to my chagrin, this represents one of the more egregious examples of these pseudo-official documents in recent years, wherein a small sect proclaims their opposition to the scientific consensus on climate change while failing to include any manner of support for that dissent. Here they flatly assert the “science is not settled,” listlessly retreating behind the aegis of NASA credentialing and supposing that banner bestows some automatic grant of credibility.
Fortunately, science doesn’t work that way. The authenticity of empirical assertions is not determined by the reputation of the organization you currently work for, previously worked for, or by your past contributions to science. Nor is it bolstered by how many other people share your particular view. After all, if the latter were true then the general public’s position on climate change would indicate no further research is necessary. Any objection to a body of accepted knowledge will acquire credibility to the extent it acquires empirical support. It’s the way understandings of the natural world have always been achieved, and these foundational tenets of science aren’t about to change now.
Instead of citing new research or even fringe studies which support their position, the 49 endorsing this letter plainly tell us how they feel about climate change and then leave out the most important part – the why! It would be like an ex-astronaut releasing a public statement that he disagrees with the accepted nutrition guidance on the consumption of trans fat and that we should all eat uncontrolled amounts of unsaturated fat. Absent any corroborating information, we shouldn’t take such a statement seriously, just as we shouldn’t take this latest miff seriously.
Many others around the blogosphere have echoed why this letter lacks any real currency, including Bad Astronomy blogger Philip Plait and Shawn Otto over at Neorenaissance. However, both dismiss this latest attack on different grounds than I will here. Mr. Plait targets the individual disciplines of these former NASA members, stating that not one has ever worked as a climate scientist. It’s true; the majority of the signers are ex-astronauts, but line of work is immaterial to the issue. One can of course be knowledgeable about a field without working directly in it. James Cameron is well-versed in marine biology despite his occupation as a film director. If a celebrity supermodel tells us that trans fat is good for us and offers confirming data, her non-involvement in nutritional science is less important than the data invoked in her conclusion. In the same way, a climatologist’s claim that global warming is not caused by humans should not be assessed solely on his or her scientific background, but on empirical authority.
Shawn Otto attacks the letter instead for the relatively small number of NASA members who signed it, stating that “more than 18,000 people currently work for NASA,” which means these 49 represent just. 0.27% of current employees. This statistic is also true, but also immaterial to the veracity of global warming or the amount of weight this letter deserves. Galileo’s and Darwin’s contemporaries adamantly and almost universally opposed their pair of groundbreaking theories before the dominion of empiricism stepped in and declared a victor.
Mr. Otto also tries to derive various motivations of those who attached their name to the letter. It could be any number of reasons, political or personal, but surely none that applies to the realm of science.
Rather, the most alarming fact about this letter is the group that sponsored it: Plants Need CO2. As Mr. Plait emphasizes, this is an organization that claims increased CO2 is good for the Earth because it is a vital substance to plants and vegetation, which provide us with oxygen. Bulletproof logic, because too much of something is never bad, right? Wrong. The last 30 years of climate research hasn’t revolved around whether carbon dioxide is one of the four essential ingredients plants need to grow (which it most certainly is), but whether human carbonization has upset the balance. Further, let’s not forget the negative effects on plants from increased CO2.
None of the facts about global warming has changed. We’ve long known the properties of CO2 and water vapor and their effects on climate. We also figured out long ago that the excess of global CO2 today is unprecedented and is inseparably linked to anthropogenic GHG production. More and more studies continue to independently verify a consistent conclusion: our current trend is an unnatural outlier. Unmitigated fossil fuel production has created an energy imbalance among the Earth’s ecosystems, cumulatively warming the air, surface and oceans.
This latest letter is nothing but a feeble attempt by its signers to leverage their ex-NASA renown to undermine the authenticity of human-caused climate disruption. Without any reason provided that should cause us to doubt the current consensus, their plea is likely to fall on deaf ears.
You can find NASA’s official response to the letter from Chief Scientist Waleed Abdalati here, who sums up the matter quite nicely:
“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.”
Feature image via NASA Shared Services Center