[Update: My original post, Burt Rutan's comments, and my responses to his comments have been copied here. That post has closed comments and will be updated with any further discussion Burt and I have, either in the massive comment thread below or independently. If you're interested in just Burt's and my discussion to date, minus the mass of additional commentary, please feel free to read the new post.]
Dear Mr. Rutan,
Ever since you won the Ansari X-Prize in 2004 you’ve been a minor hero of mine. I’ve felt that the development of private human spaceflight was the critical next step toward moving humanity off our small blue marble since I was in high school, and SpaceShipOne was the first major step in that direction. The commercialization of space travel is a large part of why I work in aerospace myself designing satellite and space vehicle electronics.
This is why I was disappointed to find that you had co-signed a Wall Street Journal commentary regarding human-caused climate disruption along with 15 other scientists and engineers. The commentary was replete with incorrect and misleading information. So much so, in fact, that I was surprised that you, as an engineer, would attach your name to it.
You may not be aware of this, but greenhouse crops are very productive because farmers take great care to ensure that the crops have optimal nutrition. The farmers ensure that the crops in the greenhouses have enough water, nitrogen, phosphorus, and other nutrients in addition to higher carbon dioxide. Without increasing all of these nutrients merely increasing carbon dioxide in the greenhouse’s air will not produce fast growing, nutritious crops. This is why the greenhouse claim made in the Journal commentary was incomplete and misleading – higher atmospheric carbon dioxide only leads to greater productivity when all other nutrients are also more available. It’s not a foregone conclusion that, outside of greenhouses, the other nutrients plants need to flourish will be more available. In fact, a great deal of research over the last few years suggests the opposite, that usable precipitation and fixed nitrogen will actually become rarer, counteracting most if not all of the improvements in crop yields and overall carbon sequestration by plants worldwide.
This is one example of incomplete and misleading information from the commentary you signed. There are at least five more. I can detail them for you if you are interested.
Mr. Rutan, as a successful engineer you have certainly developed an innate understanding that the quality of your opinions can only be as good as the information you have. In the case of human-caused climate disruption, I’m afraid that the information upon which you’re basing opinions appears to be rather poor quality. Climate realists like myself accept that the case for human-driven climate disruption is supported by multiple independent lines of evidence and that no alternative hypothesis yet presented has withstood scientific scrutiny or explained the observed climate changes. In this case, the strongest and best available data supports the proposition that humans are driving global climate disruption, that the disruptions to the Earth’s climate will continue to worsen this century, and the sooner we address the root causes of climate disruption, the better.
Mr. Rutan, if you our your people are reading this, I’d love to sit down with you sometime, engineer to engineer, and discuss why I think your opinions are based upon incorrect and incomplete data.
Very truly yours,