Saturday, 14 February 2009

Objective global climate warming change

It is always nice to find people taking an interest in things one has written, whether their interest is sparked by a desire to show the writer up as a cretin or to pat him on the back. A couple of my recent posts (here and here) have created, by the modest levels of interest this site engenders, a veritable flurry of activity. Much of that activity comprises comments from Mr W, including what might be a question. He wrote: "Perhaps you're not really interested in the science, but prefer to be ideologically driven?" I replied to this possible question then felt my reply could have been construed as rude or petulant and deleted my comment, by that time he had already answered it and confirmed that it was intended to be a question, which he then re-phrased and expanded by asking "Do you see yourself as looking objectively at the issues, or are you swayed by the `political' issues involved, as I think most involved in bog debates are?" Yes, I know he meant "blog" not "bog", but so many blog debates surrounding AGW get bogged down by people talking at cross-purposes that "bog debates" seems quite apposite.

There seems to me to be an inherent flaw in Mr W's question. It presumes that it is possible, in the current state of knowledge, to be objective about the effect of carbon dioxide in the atmosphere. I believe this to be impossible. As always we must define our terms to ensure we make ourselves clear. There is no single, definitive meaning of "objective", so I will adopt the meaning I believe to be used in science, namely "not subject to interpretation or opinion". This is my formulation, I do not claim it possesses any magic, but I do believe is accords with the way the term is generally used in science. There are two elements to objectivity in science, one is purely factual and the other is a process of comparison with established thinking and is, essentially, circular in reasoning. I can illustrate what I mean by reference to an anvil and my big toe.

If I hold an anvil in my plump sweaty hands and let go it will drop to the floor and land on my big toe. I say "Ouch". A scientist says "gravity". So, since we're doing science today rather than fat toes, what is gravity? It is two things. It is a purely factual description of what is observed - the anvil falls, something causes it to fall and we call that thing gravity. But what is gravity? What is the force that makes the anvil fall? The answer, of course, is that no one knows for certain but theories are put forward and assessed by people who claim to understand them and the most persuasive theory at any given time is treated as correct until something more persuasive comes along. Old Isaac Newton might have known a thing or two about the Cox's Orange Pippin and the Bramley, but current scientific thinking is that he was wrong in his theory about what gravity is. Ask a scientist who claims to understand gravity and he will spout a theory.

It is important, in my view, to recognise that any argument based on a theory rather than observable fact is circular. "What is gravity", "a force", "what is that force?", "it is X", "how do you know it is X?", "because Y says so", "how do you know Y is right?", "because no one has proved it isn't X".

Many theories that were accepted by scientists for generations have had to be abandoned because a newly-found fact provides definitive dis-proof. How many of us had a relative who suffered from a stomach ulcer and spent decades burping at inopportune times on the number 53 bus, saving the big one for when the snooty lady who smells of cats got on board? It's a pretty safe bet they were told in the 1950s or 60s or 70s or 80s or 90s it was caused by stress or a fatty diet. Then someone had an idea about a particular bacterium and investigated it. Lo-and-behold, the old theory went straight into the wheelie-bin in 80% or so of cases despite decades of the most eminent medical people believing it to be universally correct. Yet the original diagnosis of stress or fatty diet was objective in the state of knowledge at the time. The two strands of objectivity were seen - (i) Mr Belcher had a stomach ulcer, fact, it could be seen, it was objectively true, (ii) Mr Belcher's stomach ulcer was caused by stress and/or diet because the state of knowledge at the time gave no other explanation.

In the same way that it is fair to describe an analysis as objective because it corresponds with a theory accepted over time as being more likely than any other, so it is necessarily true that nothing about a scientific analysis can reach the status of being objective until a consistent theory has been accepted over time. In order to be accepted by any fair-minded person it must be shown to be consistent with factual observations and to be more consistent than any rival theory. There is nothing unique about science here. In every field requiring deductions and inferences to be drawn from observed facts, the deductions and inferences we draw depend on our knowledge, and our knowledge is based on our acceptance of theories promulgated by others.

So, how does this relate to Mr W's question?

First, we must differentiate between objective facts and interpretations of those facts which correspond with established theory to such an extent that it is fair to call them objective. For current purposes I assume it is a matter of objective fact that the overall proportion of carbon dioxide in the atmosphere was 280 parts per million by volume in about 1750 and it is now about 385ppm. I also assume it to be a matter of objective fact that an increase in the proportion of carbon dioxide in the atmosphere increases the capacity of the atmosphere to store heat. Beyond that we are in the realm of interpretation, as the discussion Mr W had with other commenters shows. They put forward arguments and analogies and received arguments and analogies in return, the amount of objective fact involved in both proposition and rebuttal was limited.

This, inevitably and necessarily, means that the argument is all about interpretation. Any talk of carbon dioxide being a "forcing" gas or a "driver" of the climate is, to my mind, subjective rather than objective because it relies on a theory that fails both parts of the objectivity test. Not only is the "forcing" or "driving" effect not substantiated by observed facts but it is a theory that has not been around for long and has not been able to gain general acceptance. I must qualify what I have just said because those who argue for carbon dioxide being a "forcing" gas fall into two camps, some argue for it having a widespread deleterious effect other consider it of no real consequence to anything.

Ah, yes, now we've reached the real issue.

Who gives two hoots about human activity changing the climate if it has no deleterious effect? If it comes to that, who gives one hoot? The whole issue is of purely academic interest unless it presents a real problem to human life or, if these things are of concern to you, animal and plant life. Maybe Mr W is concerned with this issue as a matter of pure science and has no axe to grind other than to ensure that obscure blogs written by fat retired lawyers in North London should be scientifically accurate. If so, I am very grateful that he should spend so much of his time trying to correct what he perceives as my errors and those of others kind enough to leave comments in my little pop-up box.

Somehow I think that might not be the case. Somehow I think he feels the need to argue a particular case for some reason other than the fun of doing so. Somehow I think he feels the need to sway the mind of someone he does not know and will almost certainly never meet. I might be wrong, I often am, but it doesn't seem to me he is engaging in an exercise equivalent to debating the number of angels who can balance on the end of a salami sausage.

His initial question was whether I am interested in the science or ideologically driven. It is impossible to be driven by ideology if you are not an ideologist and, to the best of my knowledge, I am not. The question was absurd because it supposes only two possible reasons why someone would write about the AGW Armageddon theory on his insignificant blog (or bog, if you think that a better description of my corner of the interwebnet).

He then asked me if I am more interested in the science or the politics. An error again, you cannot separate the two. The issue is no more relevant to we little people than are angels on a salami without the political aspect, and the strength of the political arguments depends on the strength of the scientific arguments. All who have the privilege of a vote and the burden of a tax man are entitled to clear explanations of why we should put our cross in one box rather than another and write one figure rather than another on the cheque we send the Treasury.

That is why I opined about what 385 parts per million by volume means to me. It puts the Armageddon theories in some sort of context. Maybe a scientifically irrelevant context, so be it, argue the case if I'm misleading myself. But don't pretend objectivity comes into the equation except at the margins because you will only mislead yourself. And that is why I cannot see Mr W's questions as questions, in each he was arguing a case not making an enquiry, even if he thinks he was being objective.


10 comments:

Anonymous said...

I have an idea of what 'Mr.W' is short for...

Pogo said...

For current purposes I assume it is a matter of objective fact that the overall proportion of carbon dioxide in the atmosphere was 280 parts per million by volume in about 1750 and it is now about 385ppm.

Maybe, maybe not... Truly objective results are *very* difficult to achieve.

Continuous monitoring of CO2 at Mauna Loa has only been running since 1958 - anything prior to that is either calculated from proxies or picked from the many and various CO2 studies done since the early-1800s. The early "chemistry" studies show a considerable degree of scatter (as indeed do the "grab samples" taken at Mauna Loa). From these it's easy to see that the actual CO2 record is not as smooth and gradual as the published figures would appear. "Spot results" show figures topping out at 400 - 550ppm in the 1820s, between 450 - 570ppm in the 1870s, around 450ppm in 1900 and the same in 1940 (Jaworowski, NZCPR Research, 2008).

One would wonder about the adviseability of placing the "prime" CO2 monitoring station atop an active volcano, but the figures reported are subject to considerable processing before publication and one perhaps might assume that, like the NASA GISS temperature figures, they are, by some arcane method, adjusted for base environmental factors.

That said, the Mauna Loa averages match those from the Global Network fairly closely - with the caveat that they're produced by the same methods and statistical/computational adjustments.

To misquote "Gilderoy Lockheart" - "Objective is as objective does Harry".

Anonymous said...

Rest assured Mr FatBigot, I do not think you’re a cretin, in fact I’m flattered that you should dedicate the bulk of two posts to reply to my comments, especially considering purpose of this post was simply to answer a simple question.

Contrary to what you believe it is certainly possible to be objective about the effects of CO2 in the atmosphere, in fact, if you read my comments you’ll discover that I do no more than support your assumption that: “it is a matter of objective fact that the overall proportion of carbon dioxide in the atmosphere was 280 parts per million by volume in about 1750 and it is now about 385ppm. I also assume it to be a matter of objective fact that an increase in the proportion of carbon dioxide in the atmosphere increases the capacity of the atmosphere to store heat.”
“store heat” is perhaps not quite correct, rather “impede the outward flow of heat” is, I think, something we can agree on. I do go a little further and say that such impedence of the outward flow of heat will result in a warmer lower atmosphere.

As far as other claims regarding catastrophies etc all I can say is I think it’s objective to say “I Don’t Know”

You state that “many theories that were accepted by scientists for generations have had to be abandond because a newly-found fact provides definitive dis-proof.”
In fact while many have been modified, very, very few theories that have survived intensive testing have been abandoned, rather such theories are built on and refined. The example you give could hardly be described as a major theory.

You also state that “any argument based on a theory rather than observable fact is circular” Mr FatBigot, theories ARE based on observable fact.

You seem to be thinking of theories in terms of hypotheses, which are simply statements or propositions assumed to be true.

I’ve referred to CO2 being a forcing, you’ve incorrectly interperated this as meaning a driver for climate change, which you label as subjective rather than an objective (even though in the previous paragraph you had, as stated accepted, an increase of CO2 as increasing the atmospheres capacity to store heat as being for the perposes of this debate, objectively correct.)

In using the term “forcing GH gas” climate scientists are referring to GH gases in the atmosphere with long residence times, ie. They have a very slow natural rate of turnover, as opposed to tropospheric H2O which remains in the atmophere for only a few days, and as a result its concentration can change rapidly in response to forcings.

Now this is the part of you post that I find most intreging, and as you say, now we’ve reached the real issue:

“His initial question was whether I am interested in the science or ideologically driven. It is impossible to be driven by ideology if you are not an ideologist and, to the best of my knowledge, I am not.”

What?!

How can you possibly claim that you’re not driven by ideology? Does the word have an entirely different meaning in the Northern Hemisphere to that which is used on this side of the world? Ideology is a set of beliefs! You do have beliefs? Certainly even the quickest of glances at your blog reveals you have strong views on many issues, even the pseudonym “FatBigot” indicates strong partisan beliefs.

Perhaps, I’ve miss interpreted what you meant, perhaps you’re claiming that even though you hold certain ideological beliefs, these beliefs don’t affect your views on AGW.

If that’s the case how do you justify putting so much time into an interest that holds only, presumably, a scientific interest to you? That charge is the basis for your sceptisicm about my integrity in what I’ve stated are my views, and surely what’s good for the goose is good for the gander.

I’m sure you’re aware that those holding the more exteme views on the consequences of AGW, “it’s bullshit” and “the end is nigh” tend to hold political views towards the right and left ends of the spectrum respectively?

As you’re someone whose views are clearly to the right of centre, and has an interest in the debate that isn’t based in science, through your own line of reasoning that you’ve applied to explain my interest in the debate it can only be concluded that your motivation to get involved is ideological, otherwise, why the interest??

Now, to address this: “Somehow I think that might not be the case. Somehow I think he feels the need to argue a particular case for some reason other than the fun of doing so. Somehow I think he feels the need to sway the mind of someone he does not know and will almost certainly never meet”

The reason that I find the debate interesting is that I find the motivations of the participants interesting, we have laymen, as you’ve observed, dedicating huge amounts of time arguing points on complex issues that they just don’t have the backgrounds on which to base reasoned opinions. We have scientists whose training should, in theory, lead them to have converging opinions based in the science, who’ve let themselves get carried away by their own ideologies into arguing points that are simply absurd.

What really interests me is socio-biology and evolutionary phycology, Humans are far more driven by instinct that reason, and in the AGW debate this is displayed beautifully!

Pogo, the most reliable measure of atmospheric CO2 prior to 1957 are ice-cores, these clearly show the rise and falls in CO2 concentrations over the last 800,000 years of between about 180ppm during the glacial periods and 280ppm during the inter-glacials. The chemical results you refer to were often collected at ground level in urban areas where, as demonstrated by such tests when conducted these days, CO2 levels can be several hundred ppm higher than throughout the well mixed majority of the atmosphere. If those tests did show accurate results for the whole atmosphere, the CO2 flux indicated by such rapid variations that those tests supposedly show would be utterly staggering.

Kind regards, Andrew W

Pogo said...

Andrew... yes, I agree that the "chemical" measurements of CO2 were, I assume, taken from non-optimal locations - probably convenient for the lab techs, ie near the lab, ie probably in urban connurbations and would presumably have been taken at ground, or close-to-, levels.

However, it would appear that CO2 concentration in the atmosphere is far from uniform. Beck, 2008, “50 Years of Continuous Measurement of CO2 on Mauna Loa” in Energy and Environment, Vol 19, No.7. reports that samples taken at Mauna loa can contain momentary levels of 600+ppm. These obviously are smoothed out by the continuous-sampling system, but tend to suggest that the chemical methods - reporting as they did, very wide swings in CO2 - are quite possibly valid results despite being "point" figures rather than smoothed averages.

Anonymous said...

Pogo, you appear to be arguing that, momentarily, CO2 concentrations for the atmosphere can spike to 600ppm, before returning to normal, a process that would involve the transition of 100's of billions of tonnes of CO2 in an instant.

Regards, Andrew W

Pogo said...
This comment has been removed by the author.
Pogo said...

Andrew, you're making an assumption too far.

There's no reason, physical or chemical, for the atmosphere to be a completely uniform fluid, indeed it is inevitable that there will be pockets where there will be higher concentrations of CO2 (and other atmospheric gases), balanced out by those that have lower concentrations - something borne out both by the early CO2 records and by the scatter information from Mauna Loa.

Anonymous said...

OK, you've moved away from advancing the notion that CO2 has been far higher in the recent past.

Certainly we agree that pockets of high concentrations of CO2 exist where there's a source. Regarding the anomalous high readings from Mauna Loa, I understand that these are attributed to local sources, your breath contains over 100 times the natural concentration of CO2, the concentrations from car exhausts is even higher, and pockets of high CO2 air can travel some distance before totally dispersing.

It is known that through the troposphere the concentration of CO2 falls SLIGHTLY with increasing altitude.

Since molecules of CO2 aren't mutually attracted the only way large pockets of significantly higher concentrations of CO2 could spontaneously form is as a result of its greater density or through chance, like flipping a coin 50,000,000,000,000 times and getting <24,000,000,000,000 heads (assuming a fair coin) it's possible but (and I'm no statistician) it's incredibly rare. As you know it takes a lot of air molecules to fill a tiny volume.

I suppose we could speculate that CO2 concentrations could build up close to the ground, or through some natural centrifuge process, but what bearing would that have on the validity or otherwise of AGW?

Regards Andrew W

Pogo said...

Andrew, I don't think that I've moved much away from the notion that CO2 may have been higher in the recent past than is taken as read now.

My original posting was based around the "objectivity" of the results collected over the various "chapters" of the past. They tend to be treated as if handed down on tablets of stone, whereas, like the temperature record, they are open to considerable interpretation and processing.

My background is in "hard science" where we were expected, nay mandated, to archive *all* the data and algorithms that were involved in deriving the published results - that's as objective as you can be. Looking at the historically assorted CO2 measurements gives one the strong impression that there has been a degree of selectivity in what gets included in the "official record" and what has, for whatever reason, been eliminated. The record is not as clear-cut as superficial examination would imply.

I'm not making any statements, either pro or con the validity of AGW, just trying to draw attention to the extreme difficulty in being "objective" - especially when we're working with data derived from natural sources rather than laboratory experiments.

I'll stop now, I think we've just about beaten this one to death! :-)

james c said...

Dear FB,

Suppose you wanted to increase the earh's temperature over 50 years. you could do this by placing reflective mirrors in the atmosphere to reflect light back to earth.

The question is how many mirrors you would need. I have no idea, but would expect they would be a very small proportion of the atmosphere.