But Never Uncertain
By Steven J. Grisafi, PhD.
One day after attending a class on systems theory while I was a graduate student at Yale University, an economics student, who also enrolled in this engineering course, started to explain to a friend of mine, another engineering graduate student, why he believed the climate of Europe was so much warmer than Connecticut. The economics graduate student was from North Africa. He asserted that our climate in Connecticut was much colder than much of Europe because of the Labrador Current. I knew he was mistaken. It is not that Connecticut was colder than it should be at its latitude but than much of Europe was warmer than it should be because of the Gulf Stream. The Gulf Stream flows northeast from the Gulf of Mexico hugging the coast of the United States until it reaches approximately the outer banks along the coast of North Carolina. Then the current continues flowing to the northeast until it collides with the Labrador Current off the coast of Nova Scotia. This collision of warm water with cold water has been the cause of the good cod fishing along the Labrador coast and undoubtedly is what attracted the Vikings to North America. A consequence of this collision is that the Gulf Stream is then deflected to the northwest coast of Europe and particularly Scandinavia. I was in a hurry and did not want to take the time to explain to my two classmates so I just said that our weather comes from the west. The Prevailing Westerlies causes all weather patterns to flow across the United States from the Pacific Ocean to the Atlantic.
Having a strong interest in fluid mechanics I have always had a strong interest in the weather. I suppose the first time I became fully aware of climate change was when I read Edward Gibbon’s “The History of the Decline and Fall of the Roman Empire.” In that monumental work Mr. Gibbon took notice of the much colder climate found in Canada than in areas of England at similar latitudes. He attributed this occurrence as due to human development of wilderness areas. Essentially, he was asserting anthropogenic climate change, but he did so on a micro-scale. While I knew that his explanation was as erroneous as the economics graduate student, I recognized that he understood an essential truth. Human development does alter the local climate. Yet, even while accepting this fact, I have always been skeptical of the assertion that the Earth is currently experiencing the initial phase of a run-away Greenhouse Effect caused primarily by carbon dioxide. Granted, the Greenhouse Effect keeps planet Earth much warmer than it would be if all radiation emanating from the Earth, and passing through its atmosphere, passed without transferring some of its energy to the atmosphere. But having a deep knowledge of both chemistry and physics I have always doubted that carbon dioxide is responsible for this.
My epiphany came one day upon reading a book that I borrowed from my local public library about fifteen years ago. As an undergraduate I learned that the carbon dioxide molecule does not have a permanent electric dipole. This I understood to be the reason why carbon dioxide is considered to be the weakest of all greenhouse gases. The book I read concerned itself with the planet Venus. In it I read that while the atmosphere of Venus is 95% carbon dioxide less than one third of the Greenhouse Effect occurring on the planet is due to carbon dioxide. Astronomers can determine this from the absorption spectrum of the light reflected from the planet. The book explained that more than two thirds of the Greenhouse Effect on the planet Venus was due to the trace gases, such as sulfuric acid vapor, comprising the remaining 5% of the atmosphere. The scales fell from my eyes as I realized that carbon dioxide could not be responsible for anthropogenic climate change here on Earth.
It is unfortunate that the strongest proponents of the assertion that carbon dioxide is causing Global Warming are not usually scientists most proficient in chemistry and physics. They are usually of the category known as “Earth scientists.” Their first error has been to equate correlation as causality. The numerous correlations, they put forth suggesting that the rise in the atmospheric concentration of carbon dioxide is the cause of various climate change observations they make, prove nothing. The only definitive proof would be from examination of the light reflected from the surface of Earth after reaching some distant point beyond the Earth’s atmosphere, such as on the Moon or planet Mars. Only then could we be certain what gases contribute which amounts to the Greenhouse Effect on planet Earth. Since we have roving laboratories on both Mars and the Moon we ought take these measurements to assess the truth before taking any action to remedy the situation.
Why we have not yet done so causes me great concern. Last week there was a seminar at the Yale School of Management. The seminar was advertised to all Yale alumni and broadcast over Zoom. So I attended. The seminar addressed the topic of sustainability in a post-COVID-19 world. As I had expected, the speakers made the customary assertions of causality via correlation for anthropogenic climate change caused by increasing carbon dioxide emissions. The opportunity for the audience to comment or pose a question was available so I did so. I gave my usual argument, as presented above, explaining that the lack of a permanent electric dipole for the carbon dioxide molecule implied that collisions with photons were unlikely to excite a vibrational mode within the molecule. My comment was ignored. For the benefit of those proponents of the “Carbon Dioxide is the Cause” conjecture I offer this brief tutorial on physical chemistry:
Question: Why does carbon dioxide lacking a permanent electric dipole make most collisions of the molecule with photons unable to excite a vibrational mode?
Answer: The interaction occurs through entanglement of their respective electric fields. Since the molecule lacks a permanent electric dipole it can only have an appreciable electric field resulting from Van der Waal’s force. This can only occur when the carbon dioxide molecule is in the vicinity of another molecule that perturbs its electron cloud when a photon collides with the carbon dioxide molecule. Three body collisions are a far less frequent occurrence than two body collisions. This is what makes carbon dioxide such a poor Green House gas. If a collision of the carbon dioxide molecule with a photon fails to excite a vibrational mode then there is no transfer of energy from the photon to the molecule, The molecule would need to achieve an excited vibrational mode such that its energy could then be passed to another molecule in the atmosphere which might then be transformed into translational energy thereby increasing the kinetic energy of the atmosphere.
Question: Why doesn’t a two body collision between a photon and a carbon dioxide molecule transfer translational energy from the photon to the molecule?
Answer: Photons have no mass. But they do have momentum. While such a collision will not transfer energy it can transfer momentum. This phenomenon is what makes the sky appear blue to our eyes. When a photon collides with any molecule of the atmosphere momentum can transfer thereby causing photons to scatter. The energy of the photon is directly proportional to its frequency. The magnitude of the momentum of a photon is inversely proportional to its wavelength. Assuming transmission through a single medium, the frequency is inversely proportional to the wavelength with the constant of proportionality being the speed of the wave in the medium. The frequency of the photon does not shift upon collision, but the direction of its momentum changes.