USA
Howard C. Hayden
Prof. Emeritus of Physics, Univ. of Connecticut, now living in Colorado
Just as the adage in criminology is to follow the money, in climatology, it is to follow the energy. All else is futile. In this essay, we will use only uncontroversial data published by the IPCC. All planets, regardless of whether they have an atmosphere or not, absorb heat from the sun and radiate that same amount back into space. Averaged over the sphere of our planet, Earth absorbs and emits 239 watts per square meter. Because of the greenhouse effect, the surface of Earth is warmer than the would-be temperature (–18 ºC), were there no greenhouse effect. According to the latest IPCC report, the average temperature of Earth’s surface is about 16 ºC, and the surface radiates 398 watts per square meter. As recognized from the very first IPCC report, the atmosphere keeps Earth 33 ºC warmer than it would be without the greenhouse effect. (The latest IPCC report would say 34 ºC, and we will use that figure.) The IPCC’s Third Assessment Report presents a formula for calculating the additional heat retention (called “forcing”) caused by an increase in atmospheric CO2 content. For a doubling of CO2, the value is 3.7 watts per square meter. Now, how much would the surface radiate (and the atmosphere retain) if the surfaces warmed by 3 ºC, the “most probable” value that models say would occur if the atmospheric CO2 concentration doubles, as may happen late in the century? Instead of radiating 398 W/m2, it would radiate 414 W/m2, as determined by the well-known Stefan-Boltzmann radiation law. That would be an increase of 16 W/m2. The atmosphere, via the greenhouse effect and all other atmospheric phenomena, “blocks” (retains) 159 watts per square meter—the difference between surface radiation and the radiation to space—causing that amount to be re-circulated. The heat retention causes the 34 ºC of warming. If CO2 doubles, the additional heat radiation to be recirculated would be 3.7 watts per square meter, a mere 2.3% increase. A 2.3% increase in the 34 ºC of warming would be 0.8 ºC. The IPCC’s claim of 1.5 ºC to 4.5 ºC of warming ought to raise eyebrows. A more direct “physics” view is to compare the 16 W/m2 that would be blocked with 3 ºC of warming with the 3.7 W/m2 that would occur due to CO2 doubling. That’s more than a 4X amplification! That 4X comes from models invoking three main positive feedback mechanisms: melting snow and ice, exposing darker, sunlight-absorbing earth; increasing humidity, with increased H2O-driven greenhouse effect; and melting permafrost, releasing methane, a GHG. Of course, CO2 does not melt snow, ice, or permafrost, nor does it raise humidity: heat does. So, the 4X amplification should apply to any heat from any source whatsoever, including excess heat caused by the 4X amplification. A little loss of snow causes some heating, which increases humidity, and the heat from the increased humidity melts a little permafrost, and so on. Heat begets 4 times as much heat.
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Necessarily, any temperature increase from any cause whatsoever, combined with the hypothetical 4X amplification, would bootstrap to an irreversible, escalating temperature. Over the 4.6-billion-year history of our planet, such temperature variations have happened countless millions of times. How, then, are we here on this very habitable planet? Our little venture of following the energy has led us to conclude that the models—one and all showing irreversible temperature rise cause by any perturbation whatsoever—are seriously in error. Perhaps it is time to start following the money.
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