Writings of a techie wizard
Fri, 25 Oct 2013
A while back, I advised climate change alarmists to get off the soapbox. Now it appears that I have to extend that advice to scientists more generally. In the course of wandering around the Intertubes, I came across this op-ed by Adam Frank, which appeared in the New York Times a couple of months ago. (Hat tip: this post by Anthony Watts, which linked to Popular Science magazine's post explaining why they were shutting down comments, which linked to the NYT op-ed.) Frank laments the fact that the public doesn't have the confidence it used to have in science:
So far, so good; I've blogged before about the same problem. But then comes this:
Sorry, Professor Frank, but you just illustrated why the tactic of denying "scientific fact" has become politically effective and socially acceptable: scientists themselves have misrepresented what is "scientific fact", using that term not just in reference to fields like evolution that have massive supporting data and a comprehensive theory to back them up, but to fields like climate science that simply are not in the same category, but which happen to fit the scientist's personal ideology.
For example: what, exactly, are these "fundamental issues in climate science that were decided scientifically decades ago"? The fact that CO2 absorbs infrared radiation? No reputable scientist denies this, and even climate scientists who do not support the so-called "consensus" around climate change alarmism, such as Richard Lindzen of MIT, will tell you that media hacks who claim that CO2 is not a greenhouse gas are just that, media hacks.
But by juxtaposing climate science with evolution, Professor Frank is inviting us to believe that climate change alarmism itself is based on "fundamental issues in climate science that were decided scientifically decades ago": that the climate science in, say, the IPCC's WG 1 Report in the AR5 draft has the same level of confidence and support behind it as the theory of evolution. And that is, how can I put this delicately, wrong. I don't want to make this a book-length post (though I will probably have more to come on this subject in the near future), and the work of showing how the so-called "consensus" trumpeted by the IPCC is, to put it bluntly, bogus, has already been done, most recently by the NIPCC, a group of scientists who want to make clear that they are not part of the "consensus" and are willing to do the grunt work of refuting it point by point. But I'll take a brief detour to give just one illustration of what I'm talking about.
A recent post on RealClimate about ocean heating contained this little gem:
The hysteria factor alone should raise red flags with scientists in other fields like Professor Frank; but let's put that aside and do some simple math to see what these numbers really mean. (We're also putting aside, by the way, any questions about whether the numbers quoted are accurate, which, since we have only had reasonably comprehensive ocean coverage since 2003, is not a trivial point; but that's another post.) This amount of heat is for the upper 2000 meters of the world's oceans. How much water is that? The surface area of Earth's oceans is 360 million square kilometers according to The Physics Factbook. That makes a total volume of water of 720 million cubic kilometers, if we assume the entire ocean is at least 2000 meters deep. But of course it isn't that deep everywhere, so we have to cut that number down some. Let's say, just for a quick calculation, that the actual amount of water is 3/4 that, or 480 million cubic kilometers. (This is probably a substantial underestimate, since the average depth of the oceans is more than 2000 meters; but we want to be conservative since we're just doing a rough calculation to put the numbers in perspective.)
But that's cubic kilometers; each cubic kilometer is a billion cubic meters, so we're talking about 480 million billion (4.8 x 1017) cubic meters. Water weighs about 1000 kilograms per cubic meter (seawater is actually somewhat heavier, but we're being conservative in our numbers), so that's 4.8 x 1020 kilograms of water.
How much will 17 x 1022 Joules raise the temperature of 4.8 x 1020 kilograms of water? Water has a specific heat of 4180 Joules per kilogram per degree Celsius, so it takes 4.8 x 1020 x 4180 = 2.0 x 1024 Joules to heat up the top 2000 meters of the ocean by 1 degree C. That means the temperature rise over the last 30 years is 17 x 1022 divided by 2.0 x 1024, which comes out to: 0.085 degrees Celsius.
You may be fidgeting in your seat about now, thinking that I have pulled a fast one. Surely the important quantity is heat, not temperature, right? And that same 17 x 1022 Joules can raise the temperature of the atmosphere a lot more than the temperature of the oceans, right?
These statements are not false, but they are also not telling the whole story. The first, obvious point left out is that direct heat transfer only occurs if there is a temperature difference. So the heat will stay in the ocean unless the ocean is warmer than the air above it; and if the ocean's temperature has only changed by 0.085 degrees C, it can't raise the temperature of the atmosphere by direct heat transfer more than that.
The second point arises from a question you might have after reading the last paragraph: what about evaporation? Even a small difference in ocean temperature will increase the evaporation rate; and evaporation transfers heat from the ocean to the atmosphere, right? Yes, that's right: but what that statement leaves out is how the heat gets transferred. Evaporation is part of the hydrologic cycle: heat gets carried by water vapor from the surface to high altitudes, where the water vapor condenses to form clouds or precipitation. When it condenses, the latent heat it was carrying gets deposited in the atmosphere; but because that is happening at altitude, it's easier for that heat to escape to space.
In other words, of the two possible ways that 17 x 1022 Joules of heat could get transferred from the oceans to the atmosphere, one will not make much difference (because the ocean temperature has only risen by 0.085 C), and the other makes it easier for that heat to escape back to space, which provides a negative feedback. Either way, to just state the amount of heat in the oceans, without talking about how it could possibly get transferred to the atmosphere and what those mechanisms entail, is not a fair presentation of this issue. (And the Hiroshima bomb thing only makes it worse.)
If you read through the NIPCC's report that I linked to above and compare it with the IPCC WG1 report (or if you have been following this issue for any significant amount of time), you will see that every specific issue you dig into suffers from the same disease: the actual science doesn't say what the IPCC "summary" says it says, and it certainly doesn't say what the hysterical rhetoric in the popular media says it says. Scientific theories that deserve the confidence Mr. Frank wants us all to give to science are not like that. There may be polemics on both sides; indeed, there are scientists, for example Richard Dawkins, who are just as vituperative, if you just look at the surface rhetoric, when defending the theory of evolution as climate change alarmists are at defending their so-called "consensus". But when you look at the actual substance behind the rhetoric, with theories like evolution, you find that the main claims that the rhetoric makes are justified. All living organisms on Earth are descended from a common ancestor. Natural selection does cause changes in the gene pools of populations of organisms.
Also, scientists in the field of evolution are quite willing to say just where the limits of knowledge are; evolutionary biologists will readily admit that many of our current beliefs about how specific species or specific structures or traits evolved are tentative, and may well turn out to be wrong when we learn more. And when biologists recommend policies to the public that have huge consequences, they can back those recommendations up, and they can demonstrate specific consequences that will happen if the recommendations are not followed. For example, biologists predicted that overuse of antibiotics would lead to the evolution of antibiotic-resistant bacteria, and sure enough, it did.
In short, a well-supported scientific theory like evolution looks very different, when you take the time to check into it, than climate science does. Yet Professor Frank likens climate science to the theory of evolution; so either he hasn't bothered to check into it, or he has decided that the difference doesn't matter. Either way, he has demonstrated why ordinary people don't trust science the way they used to: how can they, when scientists themselves are either sloppy or disingenuous when talking to the public?
Please note, by the way, that I said "scientists" just now, not "climate scientists". Adam Frank is a physicist and astronomer; his scientific work is far removed from climate science. I'm not saying that every scientist in every field has to take the time to check up on every other field; we all have plenty of demands on our time, I understand that. But a scientist does have the responsibility, when talking to the public, to not misrepresent science, in any field, not just his own. If he hasn't checked up, he should say so, and should not present what he says about the other field as fact. Being a scientist doesn't relieve you of the need to have an informed opinion if you're going to have an opinion at all; indeed, scientists are supposed to be better than the average person at recognizing that need and taking action appropriately.
It's disappointing to see Frank, and many scientists like him, not doing that. It's even more disappointing when you see that, when it suits him, Frank is perfectly willing to draw the distinction he does not draw in his op-ed. For example, here he is on life after death:
Just to be clear: I am not saying that science can never give us reliable knowledge, the kind of knowledge that does justify branding those who refuse to accept it as "deniers". We have scientific theories, such as relativity and quantum mechanics, that have been experimentally verified to extremely high accuracy. We have others, such as the theory of evolution, that, while their subject matter prevents them from being verified experimentally to the same degree, still have a mountain of evidence in their favor, with more coming in every day, and a comprehensive theoretical structure that explains the evidence and makes correct predictions. But we also have plenty of areas of science where we do not have that same level of understanding: and the real disservice to science is to fail to be honest with the public about which is which. That is what needs to be fixed if scientists like Frank want "science denial" to stop.
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