CLIMATE: by Norman StewardNews Weekly
Kyoto: why we should be sceptical
, April 23, 2005
, formerly of the UK Meteorological Office, takes us through the "hypothetical conjecture" contained in the Kyoto Protocol, based, he writes, on a concept that is unproven.Earth's atmosphere is a gas that is set in motion by heating from the sun, but strongly influenced by the Earth's gravity and rotation. We can, as we have done since Newton, formulate a set of equations to describe the resulting motion of the air. We then compute solutions of the equations, which will tell us the future behaviour of the atmosphere.
But when we do this, we find that it just doesn't fit as well as we would expect.
Meteorological organisations (such as my former employer, the UK Met Office) use the world's biggest and most expensive computers; they collect measurement data from all over the globe. They use these resources to solve the equations, as Newton taught us, and compute predictions (called forecasts) of the atmosphere's motion in an attempt to find out what the weather will be like. But, try as they might, the forecasts are, to all practical purposes, only useful for a few days into the future. Massive efforts have been made for decades to improve weather forecasts, in particular to produce forecasts that are accurate further into the future. What we find is that the real atmosphere, after typically three to five days, just goes its own way and deviates from our forecast.
When you look into weather forecasts in detail, what you find is that, after a few days, effects (motions of the air) start to emerge that are completely unexpected. They start as tiny air motions that are of no practical interest, but grow and grow until, after some days, they dominate the weather. There are phenomena in the real world that are simply not represented in our calculations. Our equations, our theory, are just not rich enough to form a satisfactory representation of the real atmosphere. Why don't we use better equations? We simply don't have anything better. In the scientific sense, we do not understand the atmosphere.
The simple fact is that fluid dynamics is one of the last great unsolved problems of classical physics. That is the main reason we can't predict next summer's weather. Just imagine the economic value of being able to predict the weather next August. You could make a fortune if you had the solution - but nobody has it. It's also the reason we can't design aircraft without use of wind tunnels; our theoretical understanding is just not good enough. Until we invent a better - i.e. a more complete and more representative, theory of fluid dynamics - our understanding of atmospheric phenomena will remain primitive.Global warming
The idea that the atmosphere might act like a greenhouse has been around for over 150 years. A Frenchman, Baron Fourier, formulated the idea very clearly in the first half of the 19th century. At the same time, it was discovered that different gases had different abilities to trap infra-red radiation, i.e., heat. In a sense, we have spent the last 100 years or so searching for this effect in our atmosphere - and we're still looking!
Weather forecasting is hard. However, compared to calculating the greenhouse effect, it's child's play. This is a fiendishly complex problem and it's no wonder that, after a century, we still don't have a solid answer. As if the (still unsolved) problem of fluid dynamics weren't enough, we also have to deal with radiation, phase changes cloudiness, vegetation, chemistry and a whole panoply of other nasty problems.
It's more complex by far than the famous Human Genome Project (in fact that's just book-keeping compared to computing the greenhouse effect). It's much harder than weather forecasting (and look at how good we are at that!). In fact, the greenhouse effect is one of the knottiest problems in physics.The Greenhouse phenomenon
Although beautifully simple, indeed compelling, in principle, the greenhouse effect turns out to be very complicated in practice. To get an idea of how complicated, let's imagine that the quantity of greenhouse gases in the atmosphere is increased. What happens? Well, initially we'd expect the atmosphere to get warmer (the old trapping of infra-red radiation from the surface); but what happens then? Many things, is the answer, each of which makes the story more complicated.
Firstly, warmer oceans means more evaporation of water into the atmosphere which means more clouds. More clouds means more reflection of solar radiation back to space, which cools the Earth, giving a nonlinear feedback loop. How much cooling will there be? We don't really know; it's too difficult to calculate.
But that's not all. Surely warming will cause the polar ice caps to melt, eliminating their reflection of incoming solar radiation; that'll bring us back to the warming situation, won't it? Yes, it would. But what happens when trees start to grow on what was tundra? The trees absorb the greenhouse gases, reducing our initial purported prime driver. So what's the net effect of replacing snow by trees in the polar regions? We don't really know; it's too difficult to calculate.
The warmer oceans have a greatly increased ability to dissolve greenhouse gases, thus removing the very cause that we first invoked - another nasty nonlinear feedback loop. How much of the additional greenhouse gases will be dissolved in the oceans? We don't really know; it's too difficult to calculate.
And so it goes on, one intractable problem after another. As I said, calculating the effect of greenhouse gases is one of the most complex problems in the physical sciences. Scientists continue to work intensively on the problem, hoping desperately for an answer, one way or the other.
But in the meantime, the politicians have resolved they can't wait for a definite answer. For one reason or another, they have made their decision, irrespective of the science, and have established the Kyoto process. Whatever the reasons behind Kyoto, it is not scientific evidence. The scientists just don't have an answer yet; nobody knows what the net effect of adding greenhouse gases to our atmosphere is.
The whole subject has been characterised by, on the one hand, incomprehension, confusion and head-scratching and, on the other, alarmism. The former feeds the latter. The more uncertainty there is, the easier it is to ring alarm bells about what might happen. Once the news reaches political circles, this of course leads to massive increases in research funding, thus further stimulating alarmism - another nonlinear feedback loop.
If we accept, for the sake of argument, that mean global temperatures are observed to be increasing, are there explanations for this other than in terms of greenhouse gases? Well, yes there are.The urban heat island
Think of Dublin airport. Temperature measurements have been made there continuously since the 1930s. Another thing that has happened continuously since the 1930s is the encroachment of Dublin city on the airport. And cities are warmer, what with all those heated buildings and people etc. This means that the thermometers at Dublin Airport have seen, over the decades, the steady advance of the warmer urban environment, so they see higher temperatures and record them dutifully.
And those higher temperatures get fed into the World Met Organisation's (WMO's) global measurement reporting system, along with the temperature measurements from all the other thermometers placed at increasingly urban and suburban locations. There has been a tendency in recent decades for thermometers to be preferentially located in accessible places, purely due to economics. So we see recorded temperatures rising. Is this global warming? Not really. In terms of the Earth as a whole, the area we're talking about is tiny. But it's the bit we measure, so we're getting unrepresentative data.Astronomical causes
There are theories that can explain global warming purely in terms of astronomical phenomena. One school of thought holds that global warming is nothing new, it actually began 18,000 years ago as the Earth started warming its way out of the Pleistocene Ice Age.
The Kyoto Protocol is predicated on the premise that the Earth's atmosphere as a whole is warming up and that the cause of this warming is greenhouse gases released by human activity. The Protocol proposes radical international measures to reduce the release of such gases. It foresees complex, elaborate and costly systems for monitoring and trading emissions. Although purportedly based on science, it is the economic aspects of Kyoto that are of greatest significance. This is reflected in the fact that the US, India and China, inter alia
, have declined to sign up to Kyoto, principally for economic reasons.
So here we are about to embark on an adventurous program to throttle the economies of many countries, a program involving enormous economic cost around the world; and it's based, as I've tried to explain above, on a hypothetical conjecture, on a concept that, although seductive, is unproven.
In addition, we have other, equally viable explanations for global warming. When we implement such radical and damaging public policies, it is my belief that we must to do so on the basis of sound information and understanding. Public policy should be rooted, as far as possible, in fact, not conjecture.
I hope I have given you some appreciation of why Kyoto fails this test. Do we have a solid enough scientific basis to justify betting our future on Kyoto? I don't think so.In conclusion
I was involved in a program to do exactly this with rain gauges in England. The overall objective was to reduce the costs of measuring and reporting rainfall. The greatest economic benefit came from removing gauges in remote locations - and that's what we did. So at the end of the program, we had a higher preponderance of urban and suburban gauges than at the beginning.(This article first appeared in The Irish Catholic on March 17, 2005.)