Climate-change ’sceptics’: myths exposed

by Richard on January 25, 2007

Johann Hari is very good in today’s Independent addressing some of the myths perpetuated by global warming deniers.

Deniers’ Myth Number One: Scientists are divided on whether man is causing global warming. In 2004, the universally-respected journal Science studied 928 randomly selected scientific papers containing the words “global climate change”. None of them - not one - disagreed with the view that global warming is being caused to a significant degree by burning fossil fuels. As Jim Baker, who was head of one of the leading scientific organisations in the US, explains, “There is a better scientific consensus on this issue than any other, with the possible exception of Newton’s Law of Dynamics.”

Deniers’ Myth Number Two: The current warming of the world is simply part of the planet’s natural cycle. After all, there were no carbon emissions when the last ice age ended - why should the current warming be due to them? There is a sliver of truth in this: natural climate change has not stopped, and it never will. But we have superimposed onto it a great blast of greenhouse gases of our own, with far stronger effect.

To understand this, you only have to grasp some basic 19th-century physics. As Professor Chris Rapley of the British Antarctic Survey explains, “There are natural greenhouse gases in the earth’s atmosphere which trap heat on the planet, keeping the surface temperature 30 degrees warmer than it otherwise would be. Since the start of the industrial revolution, we have released lots more greenhouse gases - around 1,000 billion tonnes of them. This has enhanced the natural greenhouse effect, and trapped more heat - currently 0.6 degrees. The more greenhouse gases we add, the warmer we’ll be. It’s not rocket science.”

Deniers’ Myth Number Three: The current warming in the world is all due to changes in the energy output of the Sun. In 1991, the Danish scientists Knud Lassen and Eigil Friis-Christensen found a correlation between temperature changes on Earth from 1850 onwards and sunspot activity, which usually indicate changes in the intensity of solar radiation. As the sun warmed, we warmed.

Other scientists studied this closely, and found out that they were partly right: up to 40 per cent of the planet’s warming is indeed due to solar activity. But since 1980, sunspot activity has been declining - yet temperatures down here have been soaring to the highest levels ever recorded. So while the Sun can take some of the flak, the world’s scientists agree: the other 60 per cent remains with us.

Deniers’ Myth Number Four: In the 1970s, scientists were warning about “global cooling” and a looming Ice Age. How can we now trust these warnings of global warming? In fact, in the 1970s two - literally two - scientists tentatively suggested that cooling could occur over millennia. To compare that meek, misreported suggestion by two people to the overwhelming scientific consensus from tens of thousands of climatologists is, I am sure you deniers can see now, dishonest.

Denier’s Myth Number Five: Global warming is a religion. People have always had an innate psychological need to believe in a looming apocalypse - this is just the latest version.

Precisely the opposite is the truth. Global warming is based on very close empirical observation of the real world, and deductions based on reason. If its conclusions fall into one particular niche in intellectual history, that doesn’t change the fact they are true. It is you, the deniers clinging to myths, who resemble the faithful. Far from being Galileos, you have been siding with the fossil fuel Vatican.

Quite so. These aren’t the only myths that are repeatedly trotted out by the global warming deniers, of course. My favourite is that since weather forecasters can’t predict the weather more than a few days ahead with any reliability, the predictions of climatologists are inherently unreliable. It sounds plausible at first, but is based on a fundamental misunderstanding of the difference between ‘climate’ and ‘weather’ — weather is what is happening here and now. Climate, on the other hand is an essentially statistical science. We may not be able to predict the weather reliably for the day after tomorrow, but that doesn’t preclude the possibility of making predictions for the climatic trend for the next 100 years. A simple example will suffice. If you toss a coin, you cannot predict the outcome. It’ll be heads, tails or neither (in the extremely unlikely, but entirely possible event that the coin comes to rest on its edge or gets plucked away by a passing jackdaw ;) ). However, if you toss a coin 1000 times the outcome will be more or less 500 heads and 500 tails. You can predict that with a reasonable degree of certainty. That’s the difference between climate and weather.

The reality is that almost every day there is further evidence confirming that human activity is having a profound effect on the world’s climate. Even George Bush is beginning to get it.

{ 14 comments… read them below or add one }

1

Larry B 01.26.07 at 5:33 am

Your definition of difference between weather and climate is a little less than satsifying. Weather can be thought of as the inherent variability of the atmosphere at any given time and position. What you miss here is that while climate can be discussed as time averages of weather phenomenon, it is not capable of being spatially averaged. Thus the climate at any given position is not predictable based on the mean climate over time.

Much the same as your coin flipping example, while it is true that taken to infinity the amount of heads and tails should approach 50/50 there is also nothing in statistical science that rules out a continuous run of heads or tails and the size of that run, mathematically speaking, can extend to infinity. So at any given point in a sequence you can be terribly wrong in your predictions of heads or tails if you use the global mean as your guide.

The spatial resolution problem is a recognized shortcoming in the computer models used for most of today’s predictions. They only have a spatial resolution of around 350 square miles which is bigger than many states. Thus trying to predict climate as a result of global warming for any given locale is still subject to a high amount of uncertainty and variability. Attempting to decrease this spatial resolution results in massive increases in computing time of which there isn’t enough computing power currently avaialable to run the calculations in a reasonable time.

Secondly, current computer models still leave climate change predictions on the resolution of

2

Larry B 01.26.07 at 5:53 am

Apparently some got cut off in the first post - continuing from my first post

Secondly, current computer models still leave climate change predictions on the resolution of

3

Larry B 01.26.07 at 5:56 am

Ok, one more try and I’ll skip the secondly part. My main point is :

What is particularly objectionable to me is that there seems to be a willful concealing of the current uncertainties in the climate models in discussions leading to making decisions about humanitarian and economic impact. I agree that at issue is not whether the Earth will warm, but by how much, where, when, and with what consequences for society and ecosystems.

4

malc 01.26.07 at 8:43 am

I was wondering if 928 random papers would actually have been enough to show up any that might disagree with the general agreement about climate change. Considering that “global climate change” would be buzz words there would be tens of thousands of papers that could be counted, and I would imagine that those papers that buck the trend are more likely to turn up in journals that aren’t as well renowned as Science and could easilly have been missed.

Pick twenty hairs off your head and just becuase none of them are gray doesn’t mean you don’t have any gray hairs!!

5

Richard 01.26.07 at 10:06 am

Malc - is 928 a big enough sample? That’s a fair question. One way to find out I suppose would be to see what the response was following the publication of the survey. My guess is that it was a fair sample, but any statisticians out there are welcome to comment.

Larry - I don’t see any concealing of the uncertainties, willful or otherwise. But what is certain is that the adverse effects of climate change will be felt most keenly by the poorest of the world. That makes this a matter of justice.

6

DH 01.26.07 at 2:42 pm

Richard did you read Larry’s first post before his secondly comment? I think he shows before the secondly comment how one can’t conclude what they are concluding when taking into ALL of the things Larry mentioned.

7

Richard 01.27.07 at 12:05 am

Yes, I did DH. I didn’t respond to Larry’s first comment because I was short of time. Of course the computer models have shortcomings. The climate is a very complex system! But the models have been remarkably successful in making confirmable predictions. It’s another of the global warming deniers recurring myths that the computer models don’t work. They do.

I don’t claim that the coin tossing analogy was perfect, but I do stick with it. Climate is essentially “averaged weather”.

8

Larry B 01.27.07 at 4:59 am

Well,

I try again with my discussion of the models. I’m not saying that the computers models don’t work, what I’m really getting at is that they work well for what they can model, but they aren’t comprehensive in their analysis but this isn’t often discussed. Also, modeling and confirming currently available field data using the models is entirely different than making a prediction with the model.

9

Larry B 01.27.07 at 5:12 am

Uh Richard I think your comment site doesn’t like my comments :) If you can delete comments, please delete the last one I made - it didn’t come through again.

One thing I would point out is that the government agencies here have advised that any models that make climate predictions on the order of

10

Richard 01.27.07 at 7:08 am

I apologize for the way my blog is treating your comments Larry. Cutting you off mid-sentence is very rude. I shall give it a spanking…

Again, let me see that I agree with you that the climate modls aren’t perfect. But the point is that they ave been successful at “hindcasting” - that is, starting the model at a point in the past and running it forward. The models have been able to track what actually happened very satisfactorily. This IPCC page shows this process. Furthermore, the models have been able to make real predictions, for example that global warming would be amplified in the Arctic. This has been confirmed by observation. So while the models can be improved, it is untrue to say that they are so flawed as to be no of use. (Not that that’s what you said, of course!)

11

malc 01.27.07 at 5:38 pm

this is what happens Larry when you start saying computers aren’t any goo….

12

J 01.28.07 at 4:05 am

In addition to sample size, “myth number one” doesn’t mention how many of the studies even addressed whether fossil fuels were involved. Studying whether something is happening isn’t the same as studying why it’s happening.

Myth number two: does a “myth” that the article concedes is at least partly valid qualify as a myth?

For myth number three, here’s a handy chart of “highest temperatures ever recorded”: http://www.infoplease.com/ipa/A0001375.html .

Myth number four: I don’t know how many scientists were warning us about the new ice age in the 70s, but it was, like global warming, presented as irrefutable fact when I was in school.

For myth number five, Hari misstates the issue in my view. Global warming isn’t a religion, but, at least in western culture, environmentalism might as well be.

This appears to be an attempt to deflect the most obvious argument against his subsequent remarks about Exxon-Mobil funding research debunking global warming claims. But those arguments are valid nonetheless - promotion of an ideology is an immeasurably more powerful motivator than financial gain. Moreover, proposals in Europe and the US to intimidate scientists who question anthropogenic global warming make it look like those who support the view that GW is anthropogenic are the ones lying.

I was encouraged by Hari’s remarks about Earth First; it’s refreshing to see a reporter at least begin to acknowledge, if only implicitly, the environmental movement’s racism and indifference to human suffering.

13

Larry B 01.28.07 at 5:39 am

What confuses me a lot about this whole debate is that we already have a tested and proven solution - nuclear power - to eliminate the emissions from power generation (which comprises 40% of the emission problem). However the political left in the US that is so loud about the awfulness of global warming are the first ones stop the introduction of more nuclear power plants to replace fossil fuel plants. Why do that in light of the current problems? I just don’t get it. If you think there is ignorance surrounding the global warming debate from a scientific point of view, then the left uses as much scientific ignorance to stop one of the only proven and test solutions we have to eliminating the problem.

I lived off nuclear power for several years and it was a perfectly good form of power and it was relatively cheap compared to the fossil fuel power costs. Seems like a good idea to me.

14

Richard 01.28.07 at 7:23 am

J - on #1, you’re right that “Studying whether something is happening isn’t the same as studying why it’s happening” of course. But that the planet is warming isn’t being disputed by anyone, even the most sceptical. The only controversy is the ‘why’. If scientific opinion were as divided as some try to suggest, you might just expect that to be reflected in the scientific literature.

On #2, the key word is ’simply’. No one is denying that there is natural variability in the climate. But what the deniers do is try to suggest that the changes we observe in our world are entirely the result of those natural cycles.

#3. I’m not sure of the point you’re making.

#4 - Even if you’re right about the way you were taught in school (”irrefutable fact” seems a bit strong), the issue here is what the science was saying back then. And it *is* a myth that the threat of a coming iceage had anything even remotely approaching the merest hint of the weight of science behind it that global warming does today. For one thing, as I say, the fact that the world is warming is entirely uncontroversial.

Lastly, you don’t think a broad statement like “the environmental movement’s racism and indifference to human suffering” might be overstating things just a tad? That there is racism an indifference to suffering in the environmental movement is certainly true, but to suggest that these are characteristics of the whole movement is, frankly, preposterous. imho.

Larry - if you’re going to make global warming the basis for the promotion of nuclear power, you have first to accept the case for anthropogenic gw. Some have done just that. Whether nuclear represents a realistic solution to the problem of CO2 emmissions is very doubtful in my view. The safety and security issues are non-trivial, for one thing. Fusion might be a contender, but we’re a long way from a commercial fusion reactor as I understand it. The costs of nuclear power production are controversial and hard to pin down and I’m not at all convinced it is as cheap as you suggest.

Fow what it’s worth, my view is that we should be looking at more widely distributed power generation systems rather than thinking we have to rely on large centralized power stations. There are several technologies that would make this possible. They’re not really economic at the moment, but that could easily change.

Leave a Comment

You can use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>