Two Approaches to Climate Change
The U.S. Senate has overwhelmingly voted that climate change is not a hoax. This may be a major breakthrough in scientific research. No more tedious gathering and analysis of data, no more laborious derivation of mathematical models – just convene the Senate and vote on it.
Admittedly, this is not a new idea. Francis Galton noted that when 800 villagers were asked to guess the weight of an ox at a livestock fair, the average of their guesses was startlingly close to the actual value. This approach has been extolled by Surowiecki as the "Wisdom of Crowds" and codified as the Delphi method. However, the value of this approach has been disputed:
Overall the track record of the Delphi method is mixed. There have been many cases when the method produced poor results. Still, some authors attribute this to poor application of the method and not to the weaknesses of the method itself. It must also be realized that in areas such as science and technology forecasting, the degree of uncertainty is so great that exact and always correct predictions are impossible, so a high degree of error is to be expected. Another particular weakness of the Delphi method is that future developments are not always predicted correctly by consensus of experts[.] ... If panelists are misinformed about a topic, the use of Delphi may only add confidence to their ignorance.
Moreover, why should the right to vote be restricted to senators? I worked so hard to become a scientist that I’m a bit miffed that they didn’t ask for my opinion. So here it is, for what it’s worth.
Like our senators, I know nothing about the science of climatology, but I do know a little about convection and have co-authored several experimental papers on the subject. And convection may be the key to the weather phenomena that we’ve been experiencing lately.
(The next two paragraphs are going to be a bit tedious, but please bear with me.)
When a volume of fluid is heated in the presence of gravity (or other acceleration), the heated part usually rises, and colder fluid moves in to replace it. This causes the development of a pattern of convection that depends on the properties of the fluid; the size and shape of its volume; the presence of internal and external sources of energy; and the movement, temperature, and thermal conductivity of the substances that define its boundaries.
Our climate depends on two convective systems: one in the shell of gas we call the atmosphere and the other in the layer of water we call the oceans. Both are extremely complicated. The atmosphere is stratified, of varying composition, and bounded on one side by a surface (the Earth) with a complex pattern of temperature, thermal conductivity, and radiative absorptivity and emissivity. The convection in the oceans is disrupted by a network of continents and islands and complicated by a widely varying pattern of depth. The two systems are closely coupled and interact with each other. In addition, they are rotating (which produces Coriolis forces and circular wind motion) and bounded by a radiatively cooling background of black space, which contains a moving source of radiative heating (the sun) that emits varying energy.
I think that this is too complicated a problem for anyone, including the IPCC, to thoroughly understand. As far as I could make out in a brief but bewildering attempt to fathom their reports, their models do not consider convection patterns in any detail. And without such an analysis, I don’t think any reliable predictions can be made.
I suspect that the IPCC has, perhaps unwittingly, used a variation of the Delphi method. Deep in their hearts, they felt that our prodigal use of fossil fuels was damaging our environment. And so, rather than impartially striving to unravel the problem of climate, they became – deliberately or subconsciously – biased advocates, cherry-picking and twisting the data and "Grubering" their presentation of it so as to arrive at the desired conclusion. And so, they have relied on intuitive consensus instead of evidence.
So far, the obvious evidence is strikingly equivocal; we are warming up and cooling down. Glaciers are shrinking while Antarctic sea ice is growing. Some regions are sweltering while others are freezing. We are told that last year was the hottest since 1850 and that a "historic blizzard" is besieging our East.
I think that convection may explain these paradoxes. Convection patterns can be stable, oscillatory, turbulent, or a combination thereof. As shown in the pictures here, a slight change in boundary conditions can change a stable pattern into an oscillating one. A transient disturbance can cause a marginally stable pattern to be disrupted by a burst of turbulence. And a theoretical analysis (in an old National Academy of Sciences monograph that I cannot now locate) indicates that when a change of boundary conditions causes one stable pattern to change into another, the transition period is chaotic.
Therefore, it seems plausible that the climate anomalies we’ve been experiencing simply mean that we are undergoing a period of transition from one climatic convection pattern to another and that the present transient disturbances cause some parts of our planet to be hotter and others colder. (This idea is consistent with meteorologists’ explanation of the recent “big freeze” as a shift in arctic wind patterns.) According to this interpretation, we cannot at present reliably determine whether the future will be warmer or colder. But some kind of change is happening.
As to the validity of the prefix “anthropogenic,” I don’t feel that the possibility can be ignored. The greenhouse effect seems to exist, although its magnitude and significance are debatable. In addition, it is evident from satellite photos that we have significantly changed the appearance of the Earth’s surface and therefore altered the pattern of its albedo. This might be sufficient to trigger changes in atmospheric convection patterns. On the other hand, anthropogenic effects may be insignificant compared to the natural forces that caused the torrid dry spells and ice ages the Earth has experienced throughout its history. In any case, the human race is very vulnerable to environmental changes, so that, as a matter of simple prudence, we must be watchful and prepared for any climatic eventuality.
To sum up, an intuitive consideration of the effects of convection has led me to the same conclusions as those of the senators: that climate change is not (entirely) a hoax but that the magnitude and direction of change are in doubt, and the role of man is uncertain. Maybe there’s something to the Delphi method after all.