Petitioning on climate, part 1

Nature is quite unconcerned about what people sign on petitions, so it baffles me that folks who say they're interested in the science turn to petitions to settle matters. I figure the best way to find out about it is to turn to folks who are studying the thing you're interested in. If I'm interested in bridges, I should turn to a civil or mechanical engineer who is working on designing them, and not someone with the same degree who works on sanitation systems or aircraft engines, much less someone working on nuclear physics (interesting field, and bright folks, but ... not much concerned with bridges).

Nevertheless, such a petition is now out, 'new and improved!!!' with 31,000 signers. (Ok, the new and improved is my comment, not theirs, but having been getting their mailings off and on for over a decade, I'm more than a little jaded.) This is a chance to try out my earlier comments that one needn't be a professional to weed out some sources.

Over at http://www.petitionproject.org/gwdatabase/GWPP/Qualifications_Of_Signers.html is their commentary on the qualifications of the petition signers. One thing they mention is that:

7. Engineering and general science includes 9,992 scientists trained primarily in the many engineering specialties required to maintain modern civilization and the prosperity required for all human actions, including environmental programs.

Hmm. Right off, one needn't be a professional to notice that engineering and science are different fields. I chatted some about this earlier. Why run down engineers by calling them scientists? As they say, engineering is required to maintain (I include improve) civilization. I agree; that's why I started there. It's good, important work. But it isn't science. Even stranger is what happens when you look farther down the list -- they fail to include almost any engineering discipline in their engineering total. They include elsewhere:

Environmental Engineering (473)
Computer Science (217)
Nuclear Engineering (215)
Mechanical Engineering (2,581)
Aerospace Engineering (585)
Chemical Engineering (1,640)
Agricultural Engineering (111)

So we need to add another 5,822 to the engineering tally, making it 15,814.
Hmm. Over half the signers are engineers, it turns out.

They also seem to have no biomedical engineers or industrial engineers, a couple areas I had friends in when I was in college. (Ok, you have to know something about the fields of engineering to notice this. But it isn't that specialized a bit of knowledge.)

So, let's ask a different question (ignoring, for now, that there's no more reason to believe that engineers know climatology any more than we'd assume climatologists know engineering). Is that number of engineers a large fraction of the field? The project having conducted a massive mass mailing, they should have reached a lot of the engineers. If this is a matter they generally feel strongly about (and, as the petition notes, they're looking at people who maintain the infrastructure of civilization, and the project is claiming that this is threatened), it should be a pretty high fraction. At least, say, half.

I figure the National Academy of Engineering would be a good place to look for figures on engineers. The first result on my search for "number of engineers" was:
http://www.nae.edu/nae/naehome.nsf/Multi+Database+Search/85256DAD003F352385256F8D006130A8?OpenDocument
It noted a couple of things. One was, that about 75,000 engineers are graduating each year. Another is that 6% unemployment among engineers meant 120,000 engineers being unemployed. A little arithmetic shows us that this means there are about 2,000,000 engineers in the USA.

We have two comparisons then, to the number of graduates, and to the total population. The latter is more meaningful. Even so, the number of engineering signers represents only about 20% of a single year's graduates. This is not impressive. Compared to the total number of engineers, it represents about 0.8%. Fewer than 1 in 100 engineers has signed.

Don't take my word for those numbers, of course. Check it out yourself. The 2 million is suspisciously round. On the other hand, if something like 75,000 are graduating each year, it's hard to see that 16,000 can be a large fraction of the total number of engineers. Let me know what better figures you find.

Again with no special knowledge, let's look at the medical folks. The project is including MD, DVM, and 'medical science' in their figures here. Again, my GP is a good doctor, but I wouldn't presume that he is knowledgeable about the physics of turbulent transfer (an element of climate), any more than my turbulent transfer friend is the guy I'd expect to take care of my allergies. Anyhow, let's see how many doctors and veterinarians there are vs. the 3069 signers they have. Hmm. AMA site wasn't much help, but a general search on "number of doctors" lead me to here:
http://www.usatoday.com/news/health/2005-03-02-doctor-shortage_x.htm Which gives the current (in 2005) figure at about 800,000. For veterinarians, I went with the general search since I don't know the name of their professional society. I found at http://www.bls.gov/oco/ocos076.htm#emply a figure of 62,000. This is missing a number of fields, since I couldn't figure what all the project meant by 'medical' (maybe they're including nursing degrees? Dentists? lab technicians?). If anything, then, my 862,000 total here is an underestimate. The percentage of possible signers in this category who did sign is ... 0.3%. About 1 in 300. (If we add the 2.5 million registered nurses, that percentage gets very small indeed.)

As a general reader with no knowledge of the underlying science, this just looks very bad to me.
* The project and people citing it want me to believe that there is serious, large scale, scientific opposition to the science on climate.
But:
* Their 'big' number is grossly padded by people who have not studied climate science nor worked in it.
* It isn't a 'big' number. The fields they are including are huge. To be large, we'd have to be looking at well over 1 million signers (only 1 in 3 people the fields already named). Maybe you'd consider it large if only 1 in 10 signed. But that's still more than 10 times the rate that actually did.
* It strikes my general reader eye as strange that after listing that thus and so many PhDs signed the petition, and thus and so many climatologists signed, they don't, on their list of signers, include what the field was for the PhD. Given the numbers, it's actually possible that all the PhD signers were engineers. Not likely, but if we should be impressed by the doctorate, it'd be even more impressive if we could tell what it was in.


I've labelled this 'part 1'. Part 2 will get in to some things that you probably need some mildly specialized knowledge for. It's very mild -- things like knowing that the American Geophysical Union includes many of the people who work on climate change, and that they have designated not more than 0.1% of their members as Fellows for the consistently high quality of their work. So in part 2, I'll take a look at how many AGU Fellows have signed. As an AGU member (ordinary member) I've received the mailing myself, so I'm sure that they have as well.

What is climate?

This question is one I've never been satisfied with the answers to. That probably means that there's some good science to be done coming up with a solid answer to is. Probably the best description, though not a definition, is from Robert Heinlein: "Climate is what you expect. Weather is what you get." What is missing from the description is how to decide what to expect.

Some of it, though, works very well as a practical matter as well. If you measure a temperature somewhere (my back yard at 12:30 PM), you have observed weather -- what we got at the instant, in the exact location, that we took the measurement. This is useful to know in its own right since what we experience directly as we live our lives is weather. If my backyard thermometer showed 95 F and humid, I know that it's a good time to read a book instead of do major weeding.

If I take readings of my back yard temperature for every July 23rd for the last bunch (project: how many? Why that many and not half as many or twice as many?) of years, and average them, then I have a notion of the expectation value (a formal process from statistics which you can study to answer my questions of how many years to average). This gives me an estimate of the temperature to expect -- the July 23rd temperature climate for my yard.

Weather is made of quite a few different things beyond temperature, so climate must be as well. Beyond temperature, we have expectations about the wind speed and direction (usually pretty mild around me, and mostly from the west), how often rain falls and how much falls when it does, how cloudy it will be, how often there is lightning, how deep the ground freezes in winter, ...

Given this, if you see someone say that a weather event -- a single storm somewhere, a cold temperature in some modest area (and compared to the globe, the US is a modest area) has proven or disproven something about climate, you know they're wrong. It's also why you'll see many scientists talking about climate change rather than global warming. Temperature is only one part of the climate system. Temperature, on the other hand, is one of the easiest things to measure, so many climate studies do focus on that. The science problem, though, is still the whole climate system.

Projects

My project folder has gotten unwieldy, so some things will show up here from there. The project folder (ok, it's now a shelf or two of bookcase) started when I realized that I had far more ideas than time to complete them. So I started making notes on the ideas so that at least I wouldn't forget what they were. But I'd also clear the brain a little to have room for new ideas. Some of those ideas have been published in the scientific literature, and some have sat quietly for upwards of 20 years.

A different sort of 'project' that will show up is where I'll suggest that you try something, or challenge you to answer something. In the former case, I probably know the answer and give some fair pointers to how to finish it. In the latter, I may not have the answer either; but it is a good question to have one for. Maybe some would be publishable in the scientific literature.

Probably a number of these will lend themselves to science fair projects.

Where I mention a project in a science note (like, say, the simplest meaningful climate model note) it may well also be that I don't expect you to take my word for things. If I'm talking science, you can do things yourself and come up with the same answer. I think it's a good thing to take the time and wrestle some with the guts of a problem. You'll understand a lot more that way (certainly I do). Plus, maybe I made a mistake and you can be the one to point it out. (In science this is normal and welcome. But you do have to provide more than 'ha ha, you're sooo wrong'.)

Climate is always changing

The subject line is a comment that surface surprisingly often in the literature of folks who want to deny that climate is changing, or if it isn't, that any of it is due to human activity, or if it is, then it will be good for us. Whatever. The science of interest here is the notion of climate change, how fast, how much, how often, and the like. The human side of concern ... we'll get to a bit of that as well.

As we look through the period where we have thermometers (the last 100 or so years) recording temperatures, we see that there are indeed changes from year to year (though a year is too short really to call climate) and decade to decade (a better period to average over). But this includes the period of significant human activity (the now 6+ billion of us), so doesn't necessarily tell us a lot about what the climate does without human effects.

For longer range, say the last 600-2000 years, we have climate proxies that tell us about climate without being thermometers. Tree rings and ice cores are two such sources of proxies. When we look here, we see that climate does change decade to decade, century to century, and even millennium to millenium. The changes are small, tenths of a degree for the global average (and the longer a period you average over, the smaller the changes). But they're observable and present.

Even longer term, we still have ice cores (to 800,000 years ago), and then also start looking at marine sediments (to about 100,000,000 years ago). We see here that climate still changes, even on 10,000 to 10,000,000 year time scales. A very large change, 5 C or so global average, is associated with the northern hemisphere ice age cycle. About as much is associated with the start of the Antarctic ice cap about 35 million years ago.

The exact causes for the changes are a subject of study with some good answers and some not as confident. They include carbon dioxide (greenhouse gas) changes, orbital variations (the earth's orbit isn't exactly constant), continental drift, and land surface changes.

So what do we need to consider as humans with human interests regarding climate? As scientists, we want to understand everything, through all of time. But as citizens thinking about policy, we can look at a few things. One thing is, although there have been large changes to climate before, humans weren't around for it, certainly not 6+ billion of us, many living in large cities near the ocean. Another is, these large climate changes were also associated with large extinctions. We might not want to cause climate change sufficient to drive a large extinction. During the glacial to interglacial warming 10-18,000 years ago, global human population was likely only a few million, and were largely nomadic. So when climate got bad in one area, they simply moved (or died). Today, with 6+ billion people occupying the earth in stationary cities, it'd be difficult to move out of the way if climate got bad where you were.

Perhaps the strongest indicator of our time scale of concern is human life. If change were to be small over 70 years, we might not be concerned as little would be different between our birth and death. More quickly, we might want to ensure that there was reasonable stability between the time our kids were born and the time they reached adulthood, 20ish years. Given the two, 'a few decades' becomes our time range. Cities also point us towards the few decade time scale -- it is on this scale that urban infrastructures are built and rebuilt. If changes are slow enough that 'all' we have to do it rebuild the city further inland over the next 50 years, for instance, then relatively simple practices could get us there (but this would require some consideration on how to carry it out, as people who live now in the area marked not to be rebuilt might object!).

So, while I'm very interested as a scientist in, for instance, the 100,000 year cycles of the ice ages (my first scientific paper was on it), it's just too slow to be a concern to me as a citizen. As a citizen, I'd as soon that scientists did understand the 100,000 year cycle -- the more that is understood, the more likely that good estimates can be made of the futures. But the estimates that matter are those for the next few decades to maybe a century or two.

Climate confusion

Part 3 with Dave's comments

Thirdly you have global warming, and then you have "Man Made global warming" and people start getting defensive if all of a sudden you start blaming them for the impeding end of the world unless "we all change the way we live and our lives now and this is how you do it".
Fourthly you see it in mainstream media now all too much: Everything and anything that is out of the ordinary now has some relationship to global warming, no matter how ridiculous.
So here I sit with 27,000 scientists saying one thing and another 27,000 scoffing at the huliboo. Who do I believe? I have seen calm rational debate from both sides. We've had global warming before. It would seem hard to argue that man hasn't had some effect but to what degree?

Agreed about the media thing. It's one of the things which irritates the scientists who are trying to communicate accurate, careful, correct information. People hear wild claims in the media, and then when we discuss what we really know and how well, we don't get believed (since we're not as extreme as the media reports, it's no story). ('we' by the way doesn't exactly include me. I haven't talked to the media for a long time, and it wasn't about this. Still, I do know folks who get quoted.)

One thing for you to do, with the 27,000 on either side of you, is to start looking at what they're scientists of. It turns out that the 27k saying that climate is changing and part of the reason is human activity are climate scientists, while the 27k disagreeing are doctors, chemists, nuclear physicists, ... But do the checking yourself. There's a petition, for instance, with over 17,000 signers, but very few of them are in climate sciences (but check me on that). If your mechanic says your car needs a new belt, as do the several other mechanics you take the car to, while a bunch of doctors you know say that it doesn't, do you get the belt or not? I get the belt. Being knowledgeable (about something) isn't sufficient; you have to be knowledgeable about the thing at hand.

A different thing, if you encounter folks trying to stampede you into particular actions (whether to avert climate change, or to ignore it) is to put a focus on Where's the science? If they're going on about how if you don't do everything they say 'we're all gonna die', or if they go on about if we do do anything 'we'll all be unemployed', well, no science to either claim. Move on. This is amazingly (depressingly) effective at screening out the stampeders. The very few comments in the vein of 'this is what we understand, therefore the following action would be a good idea' you can study and decide whether you agree.

I do a number of things that are advised for climate change reduction/prevention/etc., not because of any stampeder, but because it saves me money to drive a more efficient car, have a better-insulated house, etc. If it happens that also this does good for the environment, great.