Recently Kenneth Richard posted a flurry of papers showing that the CO2 climate sensitivity estimate has been trending sharply downward over the years, which means CO2’s claimed effect on warming has been highly exaggerated.
Now another opinion has come to light, further supporting the notion that the recent rise in CO2 in fact is having very little impact on our climate. Software engineer Dr. Dai Davies has experimental and theoretical (quantum mechanics) experience in gas phase, and he believes a doubling of CO2 will have “no significant role” in atmospheric thermodynamics.
Davies posted online a review paper on CO2 and climate sensitivity: Atmospheric Radiative Heat Transfer in Context.
It is said that radiative gasses (RGs, or greenhouse gasses) trap heat radiated from the Earth’s surface causing it’s temperature to rise by 33 K above the theoretical temperature with no atmosphere. The word ‘trap’ is misleading. RGs delay the radiative transmission of heat from surface to space. I estimate this delay and conclude that its average impact on atmospheric temperatures, the Radiative Delay Effect (RDE), is in the order of 0.14 [0.1 to 1] K. This result is then placed in the broader context of atmospheric thermodynamics where it complements recent work on the air-surface interaction. The combination leaves no significant role for carbon dioxide.
Davies also believes that “increased atmospheric CO2 has been highly beneficial to the biosphere as would a doubling.”
The IPCC climate consensus view of radiative dynamics is that the sun heats the Earth’s surface. The surface sheds heat through radiation and other processes. Around 88% of that radiation is trapped by RGs in the atmosphere, heating it by 33 K. They radiate much of that heat back to the surface. Surface cooling is impeded and its temperature rises. Carbon dioxide in the atmosphere reduces the gap in the water vapour absorption spectrum that allows the 12% of surface radiation to escape directly to space, so further decreasing surface heat loss. This view assumes strong positive feedbacks.
It has been claimed that these could cause runaway heating. A distinct alternate view, a total paradigm shift, is that the sun heats the surface during the day. The surface sheds heat through radiation and other processes. Around 88% of this radiation is delayed by RGs in the atmosphere, heating it by less than 1 K. Doubling CO2 in the atmosphere would increase this heating by less than 0.01 K. Meanwhile, at the surface, the intrinsic atmospheric radiation generated by molecular collisions, along with direct thermal conduction, allow the atmosphere to act as a thermal buffer reducing the daily surface temperature range and in doing so cause the surface temperature to rise by 60 K or more. This surface heating mechanism is near saturation and is in no way prone to runaway heating. The results reported here support and quantify the latter view – one in which carbon dioxide plays an insignificant role.
Scientific “debacle” needs to end rapidly
Back in the 1970s Dr. Davies spent years in experimental and theoretical work (QM calculations) in gas phase molecular spectroscopy for an MSc degree, and spent more than five years in environmental research. His work on leaded fuel showed that both sides of the debate were significantly wrong, and helped lead to breaking a deadlock.
Dr. Davies wrote in an e-mail that it is his hope that both sides of the debate will “follow the science so we can move more rapidly to an end of this debacle”.