Deal with climate reality as it unfolds
Special to Financial Post May 23, 2012
By Dr. Bob Carter
Over the last 18 months, policymakers in Canada, the U.S. and Japan have quietly abandoned the illusory goal of preventing global warming by reducing carbon dioxide emissions. Instead, an alternative view has emerged regarding the most cost-effective way in which to deal with the undoubted hazards of climate change.
This view points toward setting a policy of preparation for, and adaptation to, climatic events and change as they occur, which is distinctly different from the former emphasis given by most Western parliaments to the mitigation of global warming by curbing carbon dioxide emissions.
Ultimately, the rationale for choosing between policies of mitigation or adaptation must lie with an analysis of the underlying scientific evidence about climate change. Yet the vigorous public debate over possibly dangerous human-caused global warming is bedeviled by two things.
First, an inadequacy of the historical temperature measurements that are used to reconstruct the average global temperature statistic.
And, second, fueled by lobbyists and media interests, an unfortunate tribal emotionalism that has arisen between groups of persons who are depicted as either climate “alarmists” or climate “deniers.”
In reality, the great majority of working scientists fit into neither category. All competent scientists accept, first, that global climate has always changed, and always will; second, that human activities (not just carbon dioxide emissions) definitely affect local climate, and have the potential, summed, to measurably affect global climate; and, third, that carbon dioxide is a mild greenhouse gas.
The true scientific debate, then, is about none of these issues, but rather about the sign and magnitude of any global human effect and its likely significance when considered in the context of natural climate change.
For many different reasons, which include various types of bias, error and unaccounted-for artifacts, the thermometer record provides only an indicative history of average global temperature over the last 150 years.
The 1979-2011 satellite MSU (Microwave Sounding Units) record is our only acceptably accurate estimate of average global temperature, yet being but 32 years in length it represents just one climate data point. The second most reliable estimate of global temperature, collected by radiosondes on weather balloons, extends back to 1958, and the portion that overlaps with the MSU record matches it well.
Taken together, these two temperature records indicate that no significant warming trend has occurred since 1958, though both exhibit a 0.2C step increase in average global temperature across the strong 1998 El Niño.
In addition, the recently quiet Sun, and the lack of warming over at least the last 15 years — and that despite a 10% increase in atmospheric carbon dioxide level, which represents 34% of all post-industrial emissions — indicates that the alarmist global warming hypothesis is wrong and that cooling may be the greatest climate hazard over coming decades.
Climate change takes place over geological time scales of thousands through millions of years, but unfortunately the relevant geological data sets do not provide direct measurements, least of all of average global temperature.
Instead, they comprise local or regional proxy records of climate change of varying quality. Nonetheless, numerous high-quality paleoclimate records, and especially those from ice cores and deep-sea mud cores, demonstrate that no unusual or untoward changes in climate occurred in the 20th and early 21st century.
Despite an estimated spend of well over $100-billion since 1990 looking for a human global temperature signal, assessed against geological reality no compelling empirical evidence yet exists for a measurable, let alone worrisome, human impact on global temperature.
Nonetheless, a key issue on which all scientists agree is that natural climate-related events and change are real, and exact very real human and environmental costs. These hazards include storms, floods, blizzards, droughts and bushfires, as well as both local and global temperature steps and longer term cooling or warming trends.
It is certain that these natural climate-related events and change will continue, and that from time to time human and environmental damage will be wrought.
Extreme weather events (and their consequences) are natural disasters of similar character to earthquakes, tsunami and volcanic eruptions, in that in our present state of knowledge they can neither be predicted far ahead nor prevented once underway. The matter of dealing with future climate change, therefore, is primarily one of risk appraisal and minimization, and that for natural risks that vary from place to place around the globe.
Dealing with climate reality as it unfolds clearly represents the most prudent, practical and cost-effective solution to the climate change issue. Importantly, a policy of adaptation is also strongly precautionary against any (possibly dangerous) human-caused climate trends that might emerge in the future.
From the Financial Post via Dr. Carter in email correspondence
Bob Carter, a paleoclimatologist at James Cook University, Australia, and a chief science advisor for the International Climate Science Coalition, is in Canada on a 10-day tour. He speaks at Carleton University in Ottawa on Friday.
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Bart:
At May 25, 2012 at 5:40 pm you quote my having said (at May 25, 2012 at 1:11 pm)
And you respond saying;
Richard, the correlation holds up continuously since 1958. That’s 54 years.
I am sorry that my “logic” is not clear. In this thread I have twice tried to explain my view, most recently in the post you are answering. And I do not know how I can be more clear.
I can only point you to subsequent comments of rgbatduke and IanH both of whom are saying what I have been saying since 2005 in peer reviewed publication, at conferences and seminars, on WUWT and elsewhere. Perhaps it would help if you were to search the WUWT archives for related threads and to follow some of my debates with Engelbeen on the matter (he and I have been disputing this for more than a decade).
In this thread rgbatduke and IanH each use different language from me to say the same thing. For example, at May 25, 2012 at 4:43 pm rgbatduke says;
etc.
These statements I quote are not the first time Robert has stated an understanding identical to my own and in words which I wish I had been capable of thinking to use.
And at May 25, 2012 at 7:57 pm IanH says;
His saying to you,
“It is this fairly steady growth that people are concerned about. You haven’t explained it. You’ve completely ignored it”
is the same as my having said to you,
“The correlation may be indicating a short-term effect which is not significantly involved in the rise since 1958.”
I really, really do not know how to explain my “logic” more clearly. Sorry.
Richard
cgh:
Your post at May 25, 2012 at 7:26 pm takes knit-picking to a new level. It starts saying;
Well, you can claim whatever you like about the publicity, but you do not dispute the fact that Canada has abandoned greenhouse gas targets.
If you think a difference of opinion about the publicity of that fact “doesn’t provide great trust for the rest of it” then your lack of judgement is clear for all to see.
Richard
This argument is rubbish. Disguising it in jargon doesn’t make it less rubbish.
It isn’t steady state. C is increasing yes? The solution is exact. It works for all k. It works for big k. It works for small k. Your whole argument depends on asserting that k has to be big. But your reasons for making that assertion are total rubbish.
I’m a mathematician. You are not going to win an argument with me by using lots of jargon and trying to fudge the maths.
Bart, I followed your newer link to the graphs (including the integral graph) and again, while I do find it suggestive, it isn’t smoking-gun compelling. To make it so, you really do have to eliminate all reasonable alternatives. It isn’t enough to show that your very simple model works, you need to show that alternative models do NOT work, AND — and this is a very important and — you have to come up with a concrete physical model, not just point out a coincidence in the data. Otherwise one can easily show that smoking cigarettes causes teenage pregnancy, or any of the eight-zillion examples in stats textbooks for why correlation is not causality. There are many things that are covariant but are not plausibly causal.
On a second note: on the new graph, although my eyes aren’t what they used to be, I can pick up numerous places where CO_2 derivative increase precedes the GISS temperature. Systematically, not as a “noise” fluctuation — in fact several of the GISS temp fluctuations appear to be a lagged version of the CO_2 fluctuations. I know you are applying smoothing filters, and this may be an artifact of that, but I have to say that at the moment the best inference I could make from the graph is that when something causes the rate of CO_2 increase to jump, that same something (or the resulting CO_2 bump) cause a bump in the GISS temp. But this isn’t completely consistent — sometimes the temperature slightly leads or they move at the same time. Could it be that both CO_2 levels AND temperature are being modulated, through slightly different mechanisms, by a third causal mechanism altogether? Say rainfall/cloudiness, state of the sun, the value of the DJIA…
As they say, what’s up with that?
rgb
Regarding avoidance of confusing conincidence with causality, my advice to Bart is to accoomplish it by cross-validation. The model is tested in a sample that differs from the one from which it was built.
Richard, the only lack of judgment here was your snark. I notice that you were unable to challenge the facts. Your further lack of judgment is shown by the fact that it is important that countries publicly renounce Kyoto targets, not just slide away from them in the dark of night.
cgh:
At May 26, 2012 at 7:34 am you say to me;
I replied to your “snark” with “snark”. Don’t throw it if you don’t like it.
Bob Carter is known to me. For example, this thread has included much discussion on the carbon cycle and we shared lodgings when we were both speakers at a conference where I presented a paper on the carbon cycle. My knowledge of him tells me of his honesty.
I defended him against the snark from an anonymous troll; viz. you.
And I do not need to “challenge the facts” because Bob presents them correctly and you provide none. Your only dispute of the facts is that you differ in opinion about publicity of those facts.
My judgement is flawed: nobody has perfect judgement. And your comments show that you have no qualification to comment on the judgement of others.
Please return when – and only when – you have something to contribute.
Richard
NickB. says:
May 25, 2012 at 7:51 am
Bart,
In regards to your comment….
Anyway… in a multivariate system, correlation (even perfect correlation!) does not necessarily imply causation…..
The problem you have is that while you do seem to have a very good correlation, there is no mechanism proposed (testable or not) to explain it, and therefore you cannot rule out that the relationship is spurious.
__________________________________________
You can add to Bart’s correlation a very good mechanism. As the oceans warm CO2 is out-gassed. As oceans cools CO2 is absorbed. see: http://wattsupwiththat.com/2011/08/05/the-emily-litella-moment-for-climate-science-and-co2/ and especially the earlier thread referenced: http://wattsupwiththat.com/2011/08/05/the-emily-litella-moment-for-climate-science-and-co2/
Of course this is mitigated by plant life.
CO2 levels have been near starvation level and therefore we have had the more efficient C4 photosynthesis pathway evolve. Studies on a crop of wheat (C3) show CO2 remains steady at 300 ppm during the day at 2 meters above the crop. Other studies show tomatoes in a green house reduce CO2 by 50 ppm within minutes of sunrise. Therefore plants will grab any CO2 molecule they can get their greedy little leaves on as long as the partial pressure of CO2 is above their threshold. (If you want I will dig out the references again)
Add to higher air temperature (longer growing season) that higher CO2 means plant use less water and you get an expanded biosphere of CO2 starved plants.
As Dr. Roy Spencer said. After all, the human source represents only 3% (or less) the size of the natural fluxes in and out of the surface. With CO2 starved plants near the sources of man released CO2 emissions I doubt the CO2 would be around long enough to have time to even mix with the atmosphere. We have experimental proof CO2 will hug the ground.
A grim reminder of why CO2 sequestering is a really bad idea BTW.
The only way that man released CO2 causes additional CO2 in the atmosphere works is if you believe the unproven assumption made by Callender and Keeling that CO2 is well mixed in the atmosphere and that there is a “background CO2 level”
There is certainly evidence that this is a bogus assumption.from Ernest Beck’s historical CO2 measurements: http://www.biomind.de/realCO2/ to what AIRS is saying about mid troposphere CO2.
They talk of middle troposphere for their results. Even at this level AIRS does not see well mixing.
This is the paper that should make people realize just how close we were to a real disaster.
References on plants:
Wheat
CO2 depletion in leaf canopy
http://www.pnas.org/content/92/24/11230.full.pdf
http://www.thehydroponicsshop.com.au/article_info.php?articles_id=27
http://www.hydrofarm.com/articles/co2_enrichment.php
http://www.co2web.info/stoten92.pdf
http://i32.tinypic.com/nwix4x.png
Gail Combs:
You make good comments in your post at May 26, 2012 at 8:50 am.
Oceanic outgassing is only one of several plausible mechanisms of the observed recent change(s) to atmospheric CO2 concentration. Several, possible mechanisms are related to temperature change and others are not (e.g. altered ocean surface layer pH resulting from variations in undersea volcanism centuries in the past inducing a change to the equilibrium between atmospheric and ocean surface layer CO2 concentrations).
Indeed, Beck’s data (which you cite) suggests that response to temperature is not the predominant mechanism (but variations in undersea volcanism could be).
However, with respect, you miss the point of the discussion with Bart. I don’t think anybody has claimed Bart’s conclusion is wrong, but some of us are trying to explain to him that the available data is not capable of showing he is right.
Bart says he concludes that temperature change is the underlying cause of the recent change (i.e. throughout the period since 1958) in atmospheric CO2 concentration. He may be right (and I think he is) but the data does not provide his conclusion because other causes (e.g. undersea volcanism) are also possible.
In conclusion, I thank you for your contribution to the discussion. And, as an addendum, I point out that this reply to you is not intended to extend the debate into discussion of the ‘undersea volcanism’ hypothesis or any other plausible explanation of the observed rise in atmospheric CO2 concentration.
Richard
Ian H says:
May 26, 2012 at 3:49 am
“This argument is rubbish.”
I.e., you do not understand it. You clearly have no background or experience with actual real world systems. This is my bread and butter. You would be well advised to avoid being cocksure before you have understood my argument.
Work this out, for example:
dC/dt = ka*t-kC
Starting from zero initial condition, the output is
C = (a/k)*(k*t-(1-exp(-k*t))
It does not approach even a delayed version of a*t until the exponential has decayed.
Additionally, to counter your argument, there is no room for a linear term in the derivative – that is already taken up by the linear term in T times the scaling factor alpha in dCO2/dt = alpha*(T – T0). Game, set, match.
richardscourtney says:
May 26, 2012 at 3:28 am
I am sorry, Richard, but you are wrong, and I really cannot explain it more clearly. See above.
rgbatduke says:
May 26, 2012 at 6:34 am
“…you have to come up with a concrete physical model…”
Fine. Here’s a model. It may not be the model, but it would reproduce something very like the data, and implements commonly encountered processes in the natural world.
dC/dt = (Co – C)/tau1 + k1*H
dCo/dt = -Co/tau2 + k2*(T-To)
C = atmospheric CO2 content
H = human input
Co = nominal set point of CO2 in the atmosphere dictated by temperature
tau1 = fast time constant
tau2 = slow time constant
k1, k2 = coupling constants
tau1 being short, C will track Co tightly, rolling off H with high gain. tau2 being long, the set point Co will behave approximately as the integral of k2*(T-To) in the near term when there is a change.
rgbatduke says:
May 26, 2012 at 6:34 am
“On a second note: on the new graph, although my eyes aren’t what they used to be, I can pick up numerous places where CO_2 derivative increase precedes the GISS temperature.”
It may be an artifact of the data collection and smoothing. But, it does not matter. When you integrate the derivative, you get a 90 degree phase lag. The CO2 lags the temperature.
You can always differentiate a smooth signal enough times that the result appears to lead the input, because each differentiation introduces a 90 deg phase lead. But, down cannot be made up – the output still lags the input in a causal world.
Further to Bart’s model, the interval between 1980 and 2012 contains between 0 and 1 thirty year observed climatological events. In either case, the event count is far too low for a model to be constructed and validated.
Terry Oldberg says:
May 26, 2012 at 11:31 am
“In either case, the event count is far too low for a model to be constructed and validated.”
I’m definitely not going to put forward a model at this point and say “this is truth”. But, I can make qualitative statements about how the model has to work, given the evidence, and demonstrate that such workings are well within the bounds of ordinary, i.e., commonly encountered, systems behavior. And, the data clearly indicate that CO2 is driven by temperature, and human inputs are rapidly sequestered and have a relatively small impact.
Bart:
At May 26, 2012 at 11:22 am you say:
Say what!?
I fail to find where you have stated any flaw in what I wrote.
Please cite and quote where you have shown me to be “wrong” “above”.
Richard
Richard S Courtney says:
May 26, 2012 at 12:25 pm
You said you agreed with the statement from Ian: “It is this fairly steady growth that people are concerned about. You haven’t explained it. You’ve completely ignored it.”
I have demonstrated that Ian is wrong from two points of view: 1) the bandwidth would have to be large enough that the human input would be significantly attenuated 2) there is no room for a linear-with-time term showing up in the derivative because it is already accounted for in the temperature dependence, which has to be scaled as it is in order for the fine detail to match up.
Actually, three. I also explained previous that it is highly unlikely that a low bandwidth system exists which would eliminate the curvature of the human input from the output. Number (1) was so obvious to me that I jumped several steps forward of the position which, it became apparent, Ian was arguing.
I have also showed a system
dC/dt = (Co – C)/tau1 + k1*H
dCo/dt = -Co/tau2 + k2*(T-To)
which can replicate the qualitative characteristics of what we are observing, which demonstrates that such action is not beyond the realm of the possible. In fact, it is fairly commonplace.
I therefore conclude that the attribution of significant human forcing of the rise in atmospheric CO2 concentration observed over the last half century is falsified. You may disagree. I cannot stop you. But, I am on solid ground.
Not long ago, I saw a video on the testimony of four of the scientists. This meeting was held in the presence of a United States Senate Subcommittee. “Causes of climate change” was the subject of the review. It was quite frustrating. The Committee members had questions of the scientists, “what they should do in the United States Senate for Climate Change”? The answer …. totally disorganized.
Without the necessary and sufficient reasons, how the politicians are able to break the strong economic structures?
I read in another place that the ocean water level is rising due to the harvest of subterranean water storage. According to the statement, the amount of water vapor in the atmosphere, therefore it is growing. If this is true, then there are many reasons by which, extensive fossil resources under exploitations to be effective on the planet as well.
In accordance with one of the witnesses present at the Senate committee meeting, the (plants) of high carbon dioxide should be happy. Even with 1000 ppm! More heat means life! What about us?
The Venus with 400 degrees Celsius Weather conditions and atmospheric accumulation of carbon dioxide is a good guest house.
Bart:
I am replying to your post at May 26, 2012 at 1:41 pm which purports to explain how and where you had shown me to be “wrong” in this discussion.
Sorry. But you have not shown that.
Yes, as you say, I do agree with – and I said I agree with – IanH when he says;
Indeed, if I have no problem with your quoting my agreement with his statement as an example of what I said because I said it first and he restated it in different words.
However, that is not an example of my being “wrong”. And you have not shown it to be wrong. But you say;
[snip]
Sorry, but that is not true. I take each of your four points in turn.
Your first point says “the bandwidth would have to be large enough that the human input would be significantly attenuated”. Factually, that is not true as IanH showed at May 26, 2012 at 3:49 am when he wrote
You seem to think you have answered that in your post at May 26, 2012 at 11:22 am, but you have not.
Your second point says “there is no room for a linear-with-time term showing up in the derivative because it is already accounted for in the temperature dependence”.
But that is a description of your model. As you know, I have published a variety of different models which each matches the empirical data. You have not provided evidence to show that your model is the correct model from among the many possible models.
Your third point is actually an iteration of your first point.
And your fourth point says “I have also showed a system …”
So what? I have published 6 “systems” which each matches the empirical data and 3 of them have the anthropogenic emission as the cause of the observed rise in atmospheric CO2 concentration.
An ability to attribute a suggested cause does not demonstrate that the attributed cause is the true cause in part or in whole. Indeed, you are replicating an error made by the IPCC.
• The IPCC says the anthropogenic emission can be attributed as the cause of the observed rise in atmospheric CO2 and, therefore, the anthropogenic emission is the true cause.
• You say temperature change can be attributed as the cause of the observed rise in atmospheric CO2 and, therefore, temperature change is the true cause.
You and the IPCC are both wrong in your claim that an ability to attribute a cause indicates that the attributed cause is the true cause.
In summation, I reject your assertion that you have shown me to be “wrong”.
And you have not falsified “the attribution of significant human forcing of the rise in atmospheric CO2 concentration observed over the last half century”: you have merely demonstrated that another attribution is also possible.
Richard
The Venus with 400 degrees Celsius Weather conditions and atmospheric accumulation of carbon dioxide is a good guest house.
richardscourtney says:
May 26, 2012 at 9:38 am
Gail Combs:
You make good comments in your post at May 26, 2012 at 8:50 am….
However, with respect, you miss the point of the discussion with Bart.
_____________________________________
Actually that is why I put in the information about plants.
If the temperature is Warm:
A. The oceans outgasses.
B. However the plants sequester more CO2
If the temperature is Cool.
A. the oceans absorb CO2
B. However the plants sequester LESS CO2.
And that is just two very well know parts of the Carbon Cycle. And as you said volcanism is a wild card as Lake Nyos shows.
Then there are termite who put out more CO2 than humans. According to the journal Science (Nov. 5, 1982), termites alone emit ten times more carbon dioxide than all the factories and automobiles in the world. Natural wetlands emit more greenhouse gases than all human activities combined. (If greenhouse warming is such a problem, why are we trying to save all the wetlands?) http://ilovecarbondioxide.com/2009/04/termites-emit-ten-times-more-co2-than.html
I very much doubt we really understand the Carbon Cycle well enough to put numbers on everything. For example they just found out soil is also a major part of the carbon cycle: http://wattsupwiththat.com/2010/03/25/earth-follows-the-warming-soils-add-100-million-tons-of-co2-per-year/
BIGTIX says:
May 26, 2012 at 3:15 pm
The Venus with 400 degrees Celsius Weather conditions and atmospheric accumulation of carbon dioxide is a good guest house.
________________________________________
Venus is a Red Herring. “Atmospheric pressure on Venus’ surface is 92 times larger than earth,….” See discusions at WUWT threads.
http://wattsupwiththat.com/2010/05/06/hyperventilating-on-venus/
http://wattsupwiththat.com/2010/05/08/venus-envy
Don’t miss the opportunities…
I recently watched a video. The testimony of prominent scientists who had participated in the United States Senate subcommittee hearing. The Senators asked the scientists what the Senate should do to deal with global warming.
What was the response?
A handful of disorganized academic debate and then nothing. Disperse people around a table.
With full respect to these scientists, I’m sorry to say that policymakers of the session returned back to the Senate with empty hands.
Now the question is; should the policymakers break all the infrastructures based on what certain realities and or strong scientific reasons? Dr.Carter says the politicians have been silent for 18 months.
I read in an article by the harvest of subterraneous water storage, the amount of water vapor in the atmosphere have increased, and the sea level is rising as well. If this is true, then how can we ignore the effects of mining the vast resources of fossil fuels on the planet?
One of the scientists present at the meeting of the above testimony, stated that the increase of CO2 is good, and even up to 1000 ppm carbon dioxide, it doesn’t make sense. It has happened in the past. And the plants are very happy. (what about us?!)
The senator said that what should we do with the phenomenon of migration of species due to climate change? The scientist remained unable to answer.
The Venus with 400 degrees Celsius conditions and atmospheric accumulation of carbon dioxide is a good guest house for us, if we don’t find the right answer to the policymakers.
Richard S Courtney ( May 26, 2012 at 3:07 pm):
Logic and related topics have arisen as issues in your conversation with Bart over Bart’s model. I have some expertise in this area and would like to share my views.
You point out that you have published a variety of different models, each of which matches the empirical data. Of logical interest is the fact that, in making public policy on CO2 emissions, the policy maker can rely upon but a single model. This state of affairs raises the issue of how this model shall be selected by the policy maker. To select this model for the world’s policy makers is one of the jobs that have been taken on by the IPCC in publishing the organization’s periodic assessment reports.
A scientific model is a procedure for making inferences. Each time an inference is made, there are several candidates for being made. Logic contains the principles by which the one candidate that is correct may be discriminated from the many candidates that are incorrect. These principles are called the “principles of reasoning.”
In the articles at ( http://judithcurry.com/2010/11/22/principles-of-reasoning-part-i-abstraction/ ) and ( http://judithcurry.com/2010/11/25/the-principles-of-reasoning-part-ii-solving-the-problem-of-induction /) I argue that the principles of reasoning select that candidate which: a) minimizes the missing information or b) maximizes the missing information under constraints expressing the available information.
In selecting a model for use in policy making, the IPCC has not employed a logical process ( http://judithcurry.com/2011/02/15/the-principles-of-reasoning-part-iii-logic-and-climatology/ ). Instead, as you astutely point out, it has selected this model arbitrarily.
richardscourtney says:
May 26, 2012 at 3:07 pm
“Factually, that is not true as IanH showed at May 26, 2012 at 3:49 am when he wrote…”
And, I showed Ian was mistaken – there is only a finite time available to establish the linear trend. You can’t do it with low bandwidth.
I showed that the solution to the equation
dC/dt = ka*t-kC
is
C = (a/k)*(k*t-(1-exp(-k*t)))
If k*t is small, then this is approximately equal to
C := (a/k)*(k*t – (k*t – 0.5*(k*t)^2)) = 0.5*a*k*t^2
i.e., the integral of the input. And, that means the higher power character of the accumulated emissions has to show through. It doesn’t.
Moreover, Ian’s “solution” requires that there be a ramp in dCO2/dt which is unrelated to temperature. But, you cannot fit a significant one into the residual once you have subtracted out the alpha*(T-T0) term, and alpha is required to be what it is in order to match the fine detail.
You cannot add the emissions to the derivative. There is not room for it. You cannot have an arbitrarily long time constant – there isn’t enough time to have responded to it. The case is open and shut – the attribution of significant human forcing of the rise in atmospheric CO2 concentration observed over the last half century is falsified.
“I have published a variety of different models which each matches the empirical data.”
Show me one in which the relationship dCO2/dt = alpha*(T-T0) best holds. That is the right one, or the closest one to being right.
You can always differentiate a smooth signal enough times that the result appears to lead the input, because each differentiation introduces a 90 deg phase lead. But, down cannot be made up – the output still lags the input in a causal world.
You seem to be confusing two things. One, properties of harmonic functions, which are the only context I can think of offhand where “90 degree phase lag/lead” might make sense. Two, the fact that your proposed effect — increase in CO_2 — leads the proposed cause, increased temperature.
I can think of no possible way that CO_2 will start to rise six months before the temperature rise that supposedly is causing it to rise, yet that feature occurs several times on your graph. There is no harmonic analysis that I can see present, there are no phases — I’m just pointing out that the very correlation that you are relying on tie temperature to CO_2 rise is out of order in many, but not all, places in your graph.
Since, as you note, output lags input in a causal world, that suggests problems with your assignment of causality.
You also misunderstand my problem with “no physical model” and to “not addressing alternatives”, because while you provided me with a mathematical model, things you did not do include:
a) Deriving, or at least justifying, the model in question by means of something other than “whatever it is that sets the baseline CO_2 concentration of the atmosphere as a function of temperature”. What is it? Is it the ocean? Where is your evidence that it is the ocean? Is it the soil? Evidence and plausible model please. Is it beer drinkers, who drink a lot more beer in hot weather? Evidence and plausibility. In justifying it, don’t forget to tally up the CO_2 content of the source/sink that buffers/modulates this baseline, to be sure that it has enough to do the job, and it wouldn’t hurt to address the physical time scales of the buffering process, especially since the CO_2 reaction, when it doesn’t actually lead the temperature shifts see above, is very tightly coupled to air temperature in time.
b) Addressing all of the problems with the model you propose, not just the reasons you think it might be right. This is the sort of honesty expected of a good scientist, although perhaps few of us can rein it in enough to live up to Feynman’s standards. We’re (as your “referees”, if you like:-) trying to help you out here…;-)
c) Addressing at least the major alternative models or proposed mechanisms. It isn’t enough to show that your model works. There are almost certainly many models one can build that will work to describe the data. That’s the big problem with climate science, one people constantly complain about in the context of “Global Climate Models” on this very list, is it not — it isn’t that one can’t build a GCM or a model of CO_2 — it is that the models one builds (even if they more or less work to fit a reasonable baseline of data) are probably not unique, have many moving parts and adjustable parameters (that is, not-currently-measurable parameters) and hence degrees of freedom, and often leave something out with little justification or set the adjustable parameters according to the biases of the researchers. Anyone who has messed with nonlinear models knows from experience that there is often more than one way to skin a cat in parameter space — sometimes radically different ways that still fit the data pretty well. I’d wax poetic about complex systems at this point (usually) but we’ll skip it this time and concentrate on the need to not just assert that your own model works and might be/is right, but to show why alternatives, even if they also work, are less likely to be correct and ideally present evidence that this is the case, not just a mathematical or heuristic argument.
As I’ve repeatedly pointed out, and Richard as well — this is not saying that you are wrong. It is that you have only taken the first step or two towards demonstrating that you are right, what you have is suggestive, but not yet compelling, in part because you haven’t paid any attention at all to steps a, b, or c, and you have sloughed off the temporal ordering problem in the data without really addressing it. The latter is especially worrisome as it suggests a common cause to both the CO_2 rise and the temperature rise, one that can affect CO_2 faster and earlier than it affects the temperature.
This is an important clue! You don’t want to ignore it, you want to run it down! It is a tremendous constraint on the allowable physical models, is it not, not to mention a wound that opponents/skeptics of your suggestion can twist a knife in it at will if left unattended. We both agree that effect must follow cause, but CO_2 accelerates before the proposed cause. However, your real purpose is equally well served by finding something that causes both CO_2 derivative and temperature to vary, but not by the same pathways, so sometimes one can lead, sometimes the other, but they rarely get far apart. It’s running down things like this that might let you determine the physical mechanism — how many candidates can there be for this process? Which of the few is supported by completely independent evidence?
rgb
rgbatduke says:
May 26, 2012 at 10:01 pm
“One, properties of harmonic functions, which are the only context I can think of offhand where “90 degree phase lag/lead” might make sense.”
Not to an electrical engineer. Every L2 bounded time series has a Fourier transform which is equivalent in information content to the time series itself. The Fourier transform value at every frequency has a magnitude and a phase or, equivalently, a real and an imaginary part.
The derivative of a function has a Fourier transform which is amplified proportional to frequency, and whose phase is advanced 90deg from the transform of the function itself. Similarly, the integral of a function has a Fourier transform which is attenuated inversely proportional to frequency, and whose phase is delayed 90 deg from the transform of the function itself.
Speaking of harmonic functions: for every bounded interval, an L2 function can be fully described within that interval by a harmonic expansion (Fourier series) taking the 1st fundamental harmoinc to have a period equal to the interval length. Indeed, the Fourier Transform is essentially this expansion as the interval tends to infinity.
Something else you might consider, or which might gain additional insight – something very elementary for which you need no instruction, but which you might not have recalled: for a smooth function, every detail about what it is going to do in the future is contained within the value of the function itself at the initial time, and all its derivatives at that instant (Taylor series representation). So, indeed, you can predict and react to what it will do before it happens. Peering at the derivative gives you insight into the future. Peering at all the derivatives tells you everything that is going to happen.
Derivatives lead. They anticipate. It is why proportional-integral-derivative controllers are so ubiquitous. They could be called “present-past-future” controllers. The derivative part is what allows the controller to predict where the system is going, and apply a control impetus to head it off and shape the future in accordance with the design goals.
On a more practical note: how many times have you read about “adjustments” made to data? Do you think those adjustments are made with only knowledge of what happened prior to the adjustment? And, besides, there is lots of noise (inaccuracy) here in the signals we are evaluating. Numerically differentiating the data amplifies the noise (because of the amplification with frequency mentioned previously). So, what you think you see, and what is really happening, particularly as regards very fine detail such as this, is likely enough to be spurious.
Anyway, the upshot is, you really cannot hang your hat on there being anything noteworthy in these apparent (but not necessarily or even surprisingly) anticipatory events in the data.
As for providing you with a model, it rings to me a bit of refusing to believe it when I tell you the sky is blue until I can explain a mechanism for the sky appearing blue.
Bart says:
May 26, 2012 at 7:28 pm
“Moreover, Ian’s “solution” requires that there be a ramp in dCO2/dt which is unrelated to temperature. But, you cannot fit a significant one into the residual once you have subtracted out the alpha*(T-T0) term, and alpha is required to be what it is in order to match the fine detail.”
I am going to back off that statement. It requires only a constant (I know, duh, but in the heat of the battle, you don’t always sort things out clearly). But, my other argument still holds.
Basically, significant anthropogenic input only started about 100 years ago. By 1958 and until now, everything but a straight line trend is accounted for by the temperature relationship. That means you have about 50 odd years to have settled out the response. That puts a lower bound on the bandwidth, because otherwise, it would not have settled out by 1958.
If you think of a time constant as being approximately the inverse of the bandwidth, that means the time constant cannot be greater than about 50/3 = 16 or so years (assuming a standard settling time of 3 time constants). With that kind of bandwidth, you cannot get a significant impact on overall concentration from anthropogenic forcing.
Why? Because if we assume emissions have been growing linearly, the total dumped into the oceans and atmosphere is the rate of acceleration times 0.5*t^2. For t = 100 years, that is a factor of 5000. But, with the time constant limited to tau = 16 years, the amount remaining unsequestered in the oceans and atmosphere is about the rate of acceleration times tau*(t-tau). That is a factor of about 544, or approx 11% of the 5000. That’s roughly best you can do. That is, in rough terms, the max contribution of anthropogenic forcing to the total rise based on this evidence alone. And, I believe that it is conservative on the basis that it is likely enough that the rise in CO2 has been linear plus all the stuff accounted for by the temperature relationship since well before 1958.