![ipcc[1]](http://wattsupwiththat.files.wordpress.com/2011/06/ipcc1.jpg)
Guest Essay by Barry Brill
The timing couldn’t be worse.
On 23-26 September, scores of representatives of the world’s Environment Ministries are scheduled to meet in Stockholm to wordsmith the final draft of the Summary for Policymakers (SPM) of the key WG1 (physical science) portion of the Fifth Assessment Report (AR5) of the UN’s Intergovernmental Panel on Climate Change (IPPC).
The draft SPM, sent to governments on 2 August, is a 22-page condensation of 14 chapters comprising 1,914 pages of material discussing scientific papers that were published between 2006 and 15 March 2013.
This SPM is (or could be) a document of world-shaking importance. As Bloomberg points out – “it is designed to be used by ministers working to devise by 2015 a global treaty to curb climate change”.
The timetable for the global treaty was deferred at the Durban COP because developing countries (particularly China and India) felt that the 2013 SPM was an indispensable input to the negotiations. Governments need an authoritative up-to-date assessment of both the extent and the causes of the climate change threat, present and future.
But the SPM has been sidelined by momentous climate change events that occurred after its March cut-off date – and even after the date the draft was circulated.
Climate sensitivity
The “extent of warming” issue turns on how sensitive the planet is to increasing CO2 concentrations. Equilibrium climate sensitivity (ECS) was crudely estimated by Charney in 1979 at 3.0 ±1.5°C and that range remained more-or-less constant through all four previous IPCC reports.
During 2012, several groups of researchers noted that recent data and modern diagnostics now showed that the 30-year old 3°C mid-point had been grossly over-stated. Peer-reviewed journal papers included:
• Ring et al: estimates of climate sensitivity ranged from 1.5 to 2.0°C.
• Van Hateren: millennium-scale sensitivity found to be 2.0 ±0.3°C.
• Aldrin et al: the 90% credible interval ranges from 1.2°C to 3.5°C, with a mean of 2°C
This, of course, led to great dissension and became the major challenge faced by the lead authors of WG1. Although we don’t yet know how they finally reacted, a leaked copy of the SPM draft suggests that they mainly held to the longstanding orthodoxy.
In January 2013, the British media reported that the UK Met Office was projecting a 20-year standstill in global warming by 2017. This ‘pause’ had not been predicted by climate models. In February, IPCC chairman Pachauri admitted that the temperature data had already been flat for 17 years, while opining that a standstill of 30 years would be required to rebut the previous consensus.
Both “cause” and “extent” issues are heavily dependent on the validity of climate simulations by the contemporary Coupled Model Intercomparison Project (CMIP5), as are all IPCC projections of future planetary temperatures and their impacts. Serious scientific doubts about either ECS-related inputs or the accuracy of temperature outputs would be fatal to the credibility of the AR5.
After the March cut-off date for WG1 papers, the following 2013 papers have strongly reinforced concerns regarding the exaggeration of climate sensitivity:
• Otto et al: the best estimate of sensitivity is 30% below the CMIP5 multimodel mean.
• Forster et al: analysis of CMIP5 shows that 2/3 are above the Otto ‘likely’ range.
• Masters: median estimate of ECS is 1.98°C.
• Lewis: improved methodology shows the mode and median to be 1.6K
In congressional testimony, Judith Curry cited the Hawkins graph depicting observed trends below 90% of CMIP5 projections, and notes that warming may not resume until mid-century. James Hansen attributes the ‘hiatus’ to a combination of natural variability and lower sensitivity but predicts “temperature will rise significantly in the next few years with the nex El Nino phase.”
Temperature standstill
The temperature standstill has been apparent in the data for many years, but the tribalism of climate science rendered it unmentionable until the public disclosures of early 2013. Once spoken, it demanded an explanation – and it then became clear there was a great dearth of research on the subject. By the time researchers were ready to fill this gap, the draft SPM had already been dispatched.
During August 2013, a flood of highly influential papers have appeared:
• von Storch & Zorita[1] found that observed temperatures 1998-2012 were not consistent with 23 tested CMIP3 and CMIP5 models, even at the 2% confidence level. The inconsistency increases rapidly with trend length and a 20-year trend (ie to 2017) would lie outside the ensemble of all model-simulated trends.
• von Storch & Zorita (the same paper) concludes that ‘natural’ internal variability and/or external forcing has probably offset the anthropogenic warming during the standstill. Overestimated sensitivity may also have contributed.
• Tung & Zhou[2] reported that the “underlying net anthropogenic warming rate has been steady since 1910 at 0.07-0.08°C/decade, with superimposed AMO-related ups and downs ..”. The sharply increased CO2 concentrations of recent decades has not caused warming to accelerate, as was predicted by the models.
• Yu Kosaka & Shang-Ping Zie[3] plausibly found that climate models have vastly under-estimated natural variation. La-Nina-like cooling in the Eastern Pacific throughout the 21st century (since the PDO turned negative) has conquered the projected greenhouse warming. The 0.68°C warming trend during 1975-98 (when the PDO was positive) would have been[4] 0.4°C natural and only 0.28°C anthropogenic.
• Katz et al[5] says the critical uncertainty measures used by the IPCC are “out of date by well over a decade”. Modern statistical techniques could improve assessments “dramatically”.
• Fyfe Gillett & Zwiers[6] focused on the extraordinary gap between the temperature simulations of 37 CIMP5 models and the observed outcomes. Due to a ‘combination of errors’, the models have overestimated warming by 100% over the past 20 years and by 400% over the past 15 years.
Come the revolution…
These new papers devastate the IPCC orthodoxy that current and future global temperatures are mostly driven by greenhouse gas emissions, and will reach dangerous levels later this century. On the other hand, all older papers are blindsided by their apparent failure to take account of the recent data (standstill).
The IPCC’s 2001 report cautioned[7]: In climate research and modelling, we should recognise that we are dealing with a coupled non-linear chaotic system, and therefore that the long-term prediction of future climate states is not possible. The most we can expect to achieve is the prediction of the probability distribution of the system’s future possible states by the generation of ensembles of model solutions. This reduces climate change to the discernment of significant differences in the statistics of such ensembles.
The “dangerous anthropogenic global warming” (DAGW) hypothesis is based on a clear difference between CMIP5 runs with natural plus anthropogenic forcing, versus natural variability only. That difference now disappears when ensembles are adjusted to reflect current empirical data. It is quite conceivable that natural variabilty (including natural forcing) has historically dwarfed anthropogenic effects and will persistently do so in future.
In his seminal 1962 work, The Structure of Scientific Revolutions, Thomas Kuhn persuasively argued that science does not progress through the linear accumulation of knowledge but undergoes periodic revolutions or ‘paradigm shifts’.
In Kuhn’s view, no evidence that is incompatible with the current paradigm will be entertained during long periods of normal science. However, as anomalous results build up, science eventually reaches a crisis which drives the necessary acceptance of a new paradigm, which subsumes both the old and new results into a new framework. Kuhn calls this transformative point, revolutionary science.
2013 is ushering in a long-delayed revolution in climate science. A new paradigm is demanded which recognizes that AGW is but one non-determinative component in a ‘non-linear chaotic system’.
Dealing to the paradigm shift
All of this leaves the IPCC in a terrible bind regarding its September meeting. Should it:
• rubber-stamp a SPM that has been overtaken by events?
• add a major caveat to the state of play in March 2013, promising an addendum will be issued to cover post-cut-off papers? or
• adjourn the meeting to accomodate a crash program to re-write both the WG1 Technical Report and the consequent SPM?
The business as usual course is the worst option. With tense international negotiations riding on this document, it is far better that it be delayed than wrong – or indefensible. No government can make far-reaching policy decisions on the basis of a report which is widely believed to be obsolete before it is released.
An interim report suffers from a similar credibility deficit. Already[8], Environment departments from the USA and the European Union have formally sought more clarity on the “warming hiatus” and have asked the IPCC to include full information in the SPM.
“The recent slowing of the temperature trend is currently a key issue, yet it has not been adequately addressed in the SPM,” said the EU.
Although the draft says the trend has tapered off, the implications are unclear – causing the US to comment “a bunch of numbers are [left] up in the air without a concrete conclusion.”
Several countries, including China, seek information on the heat uptake of the oceans or other natural variances which might have depressed climate change data.
The draft SPM apparently fails to mention[9] that 30-year warming trends have declined each year since peaking in 2003. Or that the latest 10-year period (2003-12) is the coolest decade[10] since satellite records began in 1979.
WG1 has a track record of ignoring inconvenient research on grounds that it is ‘isolated’ or published in obscure journals. That can hardly be the fate of the August papers. All but one have been accepted by Nature Climate Change. Several of the authors are active contributors to IPCC reports, with Zwiers a current vice-chairman of WG1 and Fyfe a review editor.
Revolutionary climate science is under way. The question now is whether the IPCC is up to the challenge.
[1] http://www.academia.edu/4210419/Can_climate_models_explain_the_recent_stagnation_in_global_warming
[2] http://www.pnas.org/content/early/2013/01/22/1212471110.short
[3] http://www.nature.com/nature/journal/vaop/ncurrent/full/nature12534.html
[4] See http://judithcurry.com/2013/08/28/pause-tied-to-equatorial-pacific-surface-cooling
[5] http://www.nature.com/nclimate/journal/v3/n9/full/nclimate1980.html?WT.ec_id=NCLIMATE-201309
[6] http://www.nature.com/nclimate/journal/v3/n9/full/nclimate1972.html?WT.ec_id=NCLIMATE-201309
[7] 14.2.2.2 WG1 TAR IPCC
[8] http://www.bloomberg.com/news/2013-08-29/global-warming-slowdown-data-sought-in-un-climate-report.html
[9] http://www.quadrant.org.au/blogs/doomed-planet/2013/08/if-warmists-would-only-tell-the-truth
[10] http://www.skepticalscience.com/trend.php
Go Fever</b – – Wikipedia:
“In the US space industry, “go fever” is an informal term used to refer to the overall attitude of being in a rush or hurry to get a project or task done while overlooking potential problems or mistakes. “Go fever” results from both individual and collective aspects of human behavior. It is due to the tendency as individuals to be overly committed to a previously chosen course of action based on time and resources already expended (sunk costs) despite reduced or insufficient future benefits, or even considerable risks. “
Unless the IPCC takes Path Three (and more), adjourn to rewrite/redesign WG1, and revise accordingly the WG2, WG3, and SPM, they will be suffering “Go Fever”
They will not take Path Three, for the anti-carbon climate change social and political activists DO suffer Go Fever. Complete the project, meet the schedule, ignore the data warnings, hang the risks. Go Fever explains the advocacy in the AGU statement. Go Fever is behind “Carbon Pollution” in the administration. Go Fever is behind the “95% confidence” in the leaked AR5.
Go Fever was elemental in the Apollo One fire.
It caused the Challenger failure.
“Go Fever” is a charge that can and should be leveled at the authors of AR5. I think it is label that can stick and be understood by a large swath of the public in the coming debates
Go Fever – – Wikipedia:
“In the US space industry, “go fever” is an informal term used to refer to the overall attitude of being in a rush or hurry to get a project or task done while overlooking potential problems or mistakes. “Go fever” results from both individual and collective aspects of human behavior. It is due to the tendency as individuals to be overly committed to a previously chosen course of action based on time and resources already expended (sunk costs) despite reduced or insufficient future benefits, or even considerable risks. “
Unless the IPCC takes Path Three, adjourn to rewrite/redesign WG1, and revise accordingly the WG2, WG3, and SPM, they will be suffering “Go Fever”
They will not take Path Three, for the anti-carbon climate change social and political activists DO suffer Go Fever. Complete the project, meet the schedule, ignore the data warnings, hang the risks. Go Fever explains the advocacy in the AGU statement. Go Fever is behind “Carbon Pollution” in the administration. Go Fever is behind the “95% confidence” in the leaked AR5.
Go Fever was elemental in the Apollo One fire.
It caused the Challenger failure.
“Go Fever” is a charge that can and should be leveled at the authors of AR5. I think it is label that can stick and be understood by a large swath of the public.
[Mods: please delete my badly formatted 11:06 am above. Thank you.]
The science is settled. The great Railway Engineer has recently said the ‘pause’ will need to be 30 years before it means anything. Where did he get that, out of the same hat Trenbeth pulled his 2°C tipping point out of. The current 17 year hiatus is almost as long as the increase years.
Reality shows even the Warmistas aren’t in agreement, worse than we thought ‘peer’ reviewed papers continue to contradict each other many, many times over even when both claim to prove AGW.
My first thought when I heard about AGW was that a few millionths of CO2 could never affect the climate (common sense), then when you realize the planet makes many times more CO2 than people what does that say, they never talk about that, just the human cause yet do not subtract the natural CO2 from the reports of who much the (overall) CO2 has increased.
@- richardscourtney
“Izen, anyone who has read your numerous posts on WUWT knows that science is difficult for you, but your point I quote here is scientifically illiterate even by your standards.”
Numerous seems a little overstated, if my posts are ‘numerous’ how would you characterise your posting record?
But as you know I always welcome your fulsome help in clarifying the science for me.
@- “The Null Hypothesis applies. Therefore, nobody needs to devise an alternative unless and until the Null Hypothesis is overcome.
I explain the matter as follows.
The Null Hypothesis says it must be assumed a system has not experienced a change unless there is evidence of a change.”
That begs the question of what qualifies as a ‘change’.
Was the LIA a change? How about the glacial cycle that has radicaly changed the climate every few 10,000 years for the last several million?
Does a measured change in the TOA energy balance qualify as a change in the system… or not? But I see that you are restating the null hypothesis again…
@- “In the case of global climate no unprecedented climate behaviours are observed so the Null Hypothesis decrees that the climate system has not changed. ”
Ah, that helps, so you define a system change as unprecedented behavior. Any changes in the system that have happened before, no matter how large or whatever the present and past causes, are discounted.
Hmmm….
The problem with that definition of the null hypothesis is that given the very wide range of changes that the climate exhibits on all timescales I doubt there is any climate change that could be described as unprecedented.
I am afraid that we differ on what the null hypothesis is in this instance. I suspect that every climate behavior has a precedent. The present might be comparable with the PETM. As I result I would suggest that the inclusion of unprecedented is a logical error in this case. The climate behavior may change in ways that have historical parallels, but the cause may be different. For instance a rapid cooling of the climate may be the result of changes in the solar output or changes in the Earth albedo from volcanic eruptions or increasing ice albedo.
And of course the ice-age cycle is strongly mediated by the changes in CO2 levels that amplify the insolation changes from the MIlankovitch cycle.
I think the inclusion of ‘unprecedented’ in your version of the null hypothesis is a strawman. Climate science is not claiming that the climate is going to do something unprecedented, just that the cause of the present changes in the climate is unprecedented. Past increases in CO2 causing warming have not been anthropogenic.
Perhaps we could agree that a rather more sensible version of the null hypothesis would be the original one you wrote –
“The Null Hypothesis says it must be assumed a system has not experienced a change unless there is evidence of a change.”
Well there is abundant evidence of change –
http://onlinelibrary.wiley.com/doi/10.1029/2005GL024826/abstract
” Here, we extend the reconstruction of global mean sea level back to 1870 and find a sea-level rise from January 1870 to December 2004 of 195 mm, a 20th century rate of sea-level rise of 1.7 ± 0.3 mm yr−1 and a significant acceleration of sea-level rise of 0.013 ± 0.006 mm yr−2. This acceleration is an important confirmation of climate change simulations which show an acceleration not previously observed. If this acceleration remained constant then the 1990 to 2100 rise would range from 280 to 340 mm, consistent with projections in the IPCC TAR.”
http://www.sciencedirect.com/science/article/pii/S0033589497919001
“Most Arctic glaciers have experienced predominantly negative net surface mass balance over the past few decades. There is no uniform recent trend in mass balance for the entire Arctic, although some regional trends occur. Examples are the increasingly negative mass balances for northern Alaska, due to higher summer temperatures, and increasingly positive mass balances for maritime Scandinavia and Iceland, due to increased winter precipitation. ”
http://journals.ametsoc.org/doi/abs/10.1175/MWR-D-13-00046.1
“The tripole wind pattern, however, has displayed significant trends since the late 1980s. The negative phase of the tripole wind pattern corresponds to an anomalous anticyclone over northern Eurasia during winter, as well as two anomalous cyclones respectively occurring over southern Europe and in the mid-high latitudes of East Asia. These anomalous cyclones in turn lead to enhanced winter precipitation in these two regions, as well as negative surface temperature anomalies over the mid-high latitudes of Asia. The intensity of the tripole wind pattern and the frequency of its extreme negative phase are significantly correlated with autumn Arctic sea ice anomalies”
What we are in dispute about is whether these changes are the result of the increased CO2 or whether there are other explanations for the empirical observations.
And of course what the eventual magnitude of the climate changes might if the rising anthropogenic CO2 is a cause of the observed climate change.
The sensitivity of the climate to a doubling of CO2 might be indicated by how sensitive it is to other past changes. Given the very wide variations seen in the historical record I think it is difficult to make a strong argument for a very low sensitivity unless you can show that the explanation, the cause of those past climate changes were much larger in terms of energy imbalance than the present measure TOA imbalance from the anthropogenic rising CO2.
“In Kuhn’s view, no evidence that is incompatible with the current paradigm will be entertained during long periods of normal science. However, as anomalous results build up, science eventually reaches a crisis which drives the necessary acceptance of a new paradigm, which subsumes both the old and new results into a new framework. Kuhn calls this transformative point, revolutionary science.”
I can understand why an author who is not a professional philosopher of science would find the Kuhnian conceit attractive. However, the more important problem is explaining why the earlier IPCC positions diverged so radically from the empirical data and explaining why some important climate scientists are now taking empirical data seriously.
The fixed point in the mess that is climate science is Dr. Lindzen. Notice that recent developments are bringing climate science back to Lindzen’s position. It seems to me that Lindzen has always seen that climate science is immature and that he has been willing to drive that immature vehicle as well as possible. By contrast, the vision of climate science held by mainstream climate scientists is a wholly idealized vision that compulsively substitutes “what might be someday” for the immature vehicle of today.
richardscourtney say:
Sorry Richard, but it is impossible to observe causality.
We can only observe correlation, and then set up a theory about causality. This theory will be strengthening as long as the correlation continue and weaken when the correlation is missing.
@- davidmhoffer
“3. What does changes is the temperature profile from earth surface to TOA (Top of Atmosphere) with the top becoming cooler and the bottom becoming warmer. ”
May I say how refreshing it is to find a poster here who clearly understands the underlying process behind the GHG effect!
Yes, the temperature gradient increases when the amount of insulation between the surface and tropopause is increased.
@-“However, the magnitude of this change is defeated entirely by the very physics you claim are so well known:
a) CO2′s effects are logarithmic. Beyond 400 ppm, the effect diminishes so fast that any additional CO2 at this point is immaterial.”
Logarithmic in this instance means that a doubling always has the same effect. Venus rather refutes the claim that anything beyond 400ppm is an immaterial effect.
@-“b) Temperature does not have a linear response to increased CO2 which can be measured in w/m2 (watts per meter squared). P(w/m2) varies with T raised to the power of 4.”
Not quite, radiative emission varies with the fourth power of the temperature. That is the dominant negative feedback to temperature increase which constrains the effect of the positive feedbacks that I see you go on to mention.
@-” Positive feed backs are extremely rare in natural systems. Further, if feed backs were high, the climate would be incredibly unstable due to natural variability alone, and it isn’t.”
Multiple feedbacks both positive and negative are actually very common in natural systems, biology is stuffed with them, it is that very complexity of interaction between the various numerous factors that confers the incredible stability seen in many natural systems.
@-“d) Beyond that, the bulk of the positive feed back assumed by the IPCC is based on increased water vapour. All the data we have to date suggests that the increase in water vapour is absent”
Not quite all !
http://www.pnas.org/content/104/39/15248.full.pdf
Data from the satellite-based Special Sensor Microwave Imager (SSM/I) show that the total atmospheric moisture content over oceans has increased by 0.41 kg/m2 per decade since 1988.
http://journals.ametsoc.org/doi/pdf/10.1175/2007JCLI2142.1
Satellite measurements from the Atmospheric Infrared Sounder (AIRS) in the upper troposphere over 4.5 yr are used to assess the covariation of upper-tropospheric humidity and temperature with surface temperatures, which can be used to constrain the upper-tropospheric moistening due to the water vapor feedback. …Results indicate that the upper troposphere maintains nearly constant relative humidity for observed perturbations to ocean surface temperatures over the observed period, with increases in temperature 1.5 times the changes at the surface, and corresponding increases in water vapor (specific humidity) of 10%–25% °C1.
. This theory will be strengthening as long as the correlation continue and weaken when the correlation is missing.
=====
and totally fail when there’s no correlation at all
@- Theo Goodwin
“In Kuhn’s view, no evidence that is incompatible with the current paradigm will be entertained during long periods of normal science. However, as anomalous results build up, science eventually reaches a crisis which drives the necessary acceptance of a new paradigm, which subsumes both the old and new results into a new framework. Kuhn calls this transformative point, revolutionary science.”
Kuhn was hoisted by his own petard.
His ideas were a passing paradigm, abandoned when evidence of how ideas and concepts actually evolve in science were found to be incompatible with his hypothesis. Try D. Shapere for a devolution of Kuhn. (grin)
izen:
I am replying to your post at September 1, 2013 at 11:22 am
http://wattsupwiththat.com/2013/08/31/can-the-ipcc-do-revolutionary-science/#comment-1405605
in reply to my post at September 1, 2013 at 9:57 am
http://wattsupwiththat.com/2013/08/31/can-the-ipcc-do-revolutionary-science/#comment-1405531
Several people gave curt rejections of your post but I tried to inform you of your error by explaining the Null Hypothesis to you. Sadly, my attempt failed because it seems you were determined to misunderstand.
As I took the trouble to explain for you
The Null Hypothesis says it must be assumed a system has not experienced a change unless there is evidence of a change.
We are discussing the present global climate system which has been recovering from the Little Ice Age (LIA) for centuries. Any alteration to that system would be a change.
And the recovery from the LIA seems to have been a steady rise with periods of ~30 years of warming interrupted by periods of ~30 years of lack of warming or slight cooling. There is no evidence of any kind that the climate system which is recovering from the LIA has changed; none, zilch, nada.
As I said to you
We are discussing the present climate system. The possible “unprecedented climate behaviours” of interest pertain to the present climate system which has been recovering from the LIA for centuries.
The Earth has had several climates in the past; e.g. global and interglacial.
Your talking about those is simple evasion. We are NOT in those climate systems.
However, on the basis of your history, I am willing to accept that your inability to understand was stupidity and not egregious.
Richard
One point that Barry Brill did not make is that whilst all these ‘new’ papers/studies may not find their way into AR5 because of late publication (ie., being published after the cut off date), these ‘new’ papers will have been read by those writing and finalising AR5 and these ‘new’ papers ought from an objective standpoint make the claim that man is primarily responsible for the late 20th century warming less certain, not more certain.
Irrespective as to whether these ‘new’ papers find their way into AR5, the certainty behind AGW should not be increasing up to the 97% band, but should in fact (by which I mean based on an objective view point) be decreasing from the level of certainty that was expressed in AR4.
this follows from the fact that model projections are departing increasingly from real observational/ empirical evidence and the fact that we do not know what has brought about the pause, and why and how this has occurred, makes AGW less certain not more certain. the pause was not predicted by the models, and prima facie runs contrary to AGW if that theory rests on the bedrock that increasing levels of CO2 results in warming.
To summarise, I am saying that even iif the IPCC choses not to comment on these new papers, their very existence ought to have an effect on the conclussions drawn by the IPCC. Personally, I do not see how they expect to get away with the claim that AGW is happening is more certain than it was when AR$ was published and before such time that there was a lengthy pause in the warming..
I have been surprised to find very little data about the magnitude of the century-to-century variation in global temperatures. I have submitted a paper giving an estimate from ice core records of the past 8000 years showing a standard deviation of 0.98+/-0.15 deg C per century, which means that any anthropogenic temperature signal is probably buried in the natural noise. The IPCC in early drafts of the SPM made a significant change – whereas previously (AR4) it had said AGW was “most likely” responsible for most of the observed global warming, in draft AR5 it said AGW was “extremely likely” to have caused at least half of the observed warming. The subtle difference between these two statements may confuse many commentators, as I am sure it was intended to do.
Jan Kjetil Andersen:
Your post at September 1, 2013 at 12:06 pm is wrong on two counts.
It is at
”
Firstly, I did NOT say causality could be observed.
I said causality cannot be assumed when there is no discernible effect resulting from a putative cause. That is a fundamental scientific principle which I explained.
Secondly, it is not true that we “can only observe correlation”. We can also observe coherence.
Both correlation and coherence can each and both provide information pertaining to causality.
Correlation is a mathematical relationship between two parameters. If the correlation is known over the length of the data sets, then their correlation indicates the magnitude of a change in one parameter that is expected when the other parameter changes by a known magnitude.
Correlation does NOT indicate a causal relation between two parameters.
But
Absence of correlation indicates absence of a direct a causal relation between two parameters.
Coherence of two parameters indicates that when one parameter changes then the other parameter changes later.
Coherence can disprove that change of one parameter causes change in the other; i.e. if change in parameter A follows change in parameter B then the change of A cannot be the cause of the change of B (because a cause cannot occur after its effect).
So,
1.
absence of correlation indicates absence of a direct causal relationship
and
2.
when there is a direct causal relationship then coherence indicates which of the two parameters is causal.
Furthermore, coherence in the absence of correlation is strongly suggestive that both parameters are affected by another parameter (or other parameters).
For example, leaves fall off trees soon after children return to school following their summer break.
The coherence is great; i.e. both effects occur each year.
But the effects do not correlate; i.e. the number of returning children is not indicative of the number of falling leaves.
In this example, the time of year is the additional parameter which causes children to return to school and the leaves to fall off trees.
So, if it is known that there is a causal relationship between two parameters. The coherence between the parameters indicates which is causal.
Importantly, if there is no correlation and no coherence between two parameters then it has to be assumed that there is no discernible causal relationship between the parameters.
Richard
The IPCC must be trying really hard to find more than a few scientist and railway engineer that will lend their name to such a farce .Until the IPCC can explain the interrelationship between climate variables the rest of what they claim about humans direct influence on climate is nothing more the misleading speculation..Everything humans do has some signature in the enviroment but claiming humans or CO2 is causing global warming (climate change)is so boguss . Is the doubling of CO2 causing global cooling of the past 15 years ? Fire the IPCC for abuse of the public trust .
izen says:
September 1, 2013 at 12:35 pm
You posted to the wrong person. I was quoting the author of the article. Kuhn has become nothing more than an interesting exercise for graduate students.
Frank says:
August 31, 2013 at 10:05 pm
Smashingly good post. Alarmist climate scientists constantly mention Chaos Theory but they never use it except as an excuse. No climate scientist presents calculations and reasoning that are typical of chaos theory as they argue for particular conclusions. None of them have offered hypotheses about “attractors” in climate, at least not as “attractor” is defined technically in Chaos Theory. But it seems that all of them, yes even the best, are willing to trot out Chaos Theory as an excuse at the drop of a hat. Whenever they mention Chaos Theory, they should be seriously challenged immediately.
Climate scientists do not understand probability. They have not a clue about differences between objective and subjective probability estimates. Physicists use probabilities in their ordinary work all the time but climate scientists seem to think that their use of probabilities excuses them from the methodological guidelines that physicists work under.
Joel Hammer says:
September 1, 2013 at 9:48 am
> A bit off topic, but, can somebody tell me whatever happened to methane?
Basically, the methane concentration stopped rising after people started wringing their hands over it. With a nearly level concentration, it no longer portends doom.
See http://www.windows2universe.org/earth/Atmosphere/images/methane_atmosph_concentr_1984_2004_big.gif
http://scienceandpublicpolicy.org/originals/atmospheric_methane_concentrations.html
Some of the leveling may be from changes in rice growing and keeping paddies flooded for less time, but I don’t think it’s confidently known.
As the links above show, the IPCC overestimated its rise, so they’d probably rather ignore it than explain it.
izen says:
September 1, 2013 at 12:14 pm
>>>>>>>>>>>>
Logarithmic in this instance means that a doubling always has the same effect. Venus rather refutes the claim that anything beyond 400ppm is an immaterial effect.
Yeah, you can’t argue the physics so you throw in a reference to Venus hoping that it will distract the reader from the physics. Since you’ve stipulated to the fact that doubling has the same effect, let’s do the math. Direct effects of CO2 doubling are thought to be in the range of 1 degree. So, in order to get 2 degrees of warming from current concentrations at roughly 400 ppm, we’d need 400 x 2 x 2 = 1600 ppm. At current rates of CO2 increases, that’s 800 years from now. To get to Venus type atmosphere we’d need millions upon millions of years, which is why the reference is completely meaningless.
@-”b) Temperature does not have a linear response to increased CO2 which can be measured in w/m2 (watts per meter squared). P(w/m2) varies with T raised to the power of 4.”
Not quite, radiative emission varies with the fourth power of the temperature.
Not quite? That’s exactly what I said!
Multiple feedbacks both positive and negative are actually very common in natural systems, biology is stuffed with them
We’re not discussing biology, we’re discussing physics, in which positive feed backs are exceedingly rare.
Not quite all
http://www.pnas.org/content/104/39/15248.full.pdf
Data from the satellite-based Special Sensor Microwave Imager (SSM/I) show that the total atmospheric moisture content over oceans has increased by 0.41 kg/m2 per decade since 1988.
Really? How do you stuff 0.41 kg of water into a two dimensional plane?
You’ve cherry picked the end points in any event, and I’ve spent enough time debunking you for one day. Your grasp of the physics is exceedingly weak, as demonstrated by your clear inability to understand that neither Venus nor biologic systems are of any relevance in the discussion.
richardscourtney say:
Well, you did say:
That is a direct quote from your post September 1, 2013 at 9:57 am
Look at that last part: “GHGs are observed to increase global temperature”
That is to observe that GHGs are a cause of increase in global temperature isn’t it?
And that mean the same as to observe causality.
Jan Kjetil Andersen says:
September 1, 2013 at 2:25 pm
You wrote to Richard:
That is a direct quote from your post September 1, 2013 at 9:57 am
Look at that last part: “GHGs are observed to increase global temperature”
What you failed to see in Richard’s definition of the Null Hypothesis were the words “unless and until” that preceded “GHGs are observed to increase global temperature. Leaving that out kinda changes the meaning, don’t ya think?
Jan Kjetil Andersen:
I do not know what you are trying to prove with your silly post which quotes me out of context at September 1, 2013 at 2:25 pm .
I actually wrote
You queried my meaning and I added clarification together with information on coherence which you said you lacked. Your response is to knit-pick my choice of words.
I think my meaning was clear and your knit-picking does not induce me to change my wording.
I would be pleased to discuss any substantive point you have to make. Knit-picking choice of words and quoting out of context is not making a substantive point.
Richard
Vieras says:
August 31, 2013 at 10:55 pm
“The next IPCC report will be just as alarmistic as before and it will be released with a tsunami of media articles trying to restart the whole failed meme again. They will be more sure than ever. Does anyone want to bet
I’m wrong.”
Dear Vieras, I hope and pray you are wrong and will bet $1,000.00*
that you are. I have lost every bet I’ve made in the last few years and
hope my string of failed wagers will be reversed and the IPCC will come
clean. I fear you are right and when I lose the bet I will have to pay
you in Monopoly Money after I’ve sold Boardwalk and Park Place.
If you lose the bet you will owe me nothing. We’ll both be too happy
celebrating together here on WUWT with Anthony and hundreds of
friends. L8tr, John
2014: IPCC Report. The world continues to warm from CO2 but natural variability is higher than previously thought. Still the first decade in this century was the warmest on record. More effort on climate sensitivity due to CO2 will help improve future estimates of warming.
2021: IPCC Report. As previously reported natural variability continues to weaken the long term warming trend due to CO2 although the second decade in the 21st century was the second warmest on record. Progress has been made on CO2 sensitivity to warming and has resulted in a slight downward revision. While hopeful, this revision does little to reduce concern about the future catastrophic trend in warming.
2028: IPCC Report. As predicted the revised estimates of climate sensitivity are in-line with measured temperature once natural variability is taken into account. It is likely that the decade 2020-2029 will be the third warmest decade on record. We have reached the point at which governments are now fully aware of the impacts of climate change and have made important changes to reduce the future growth of CO2 from fossil fuels. As a result of this IPCC-led effort, this will be the last report as the IPCC has met its goals and its members will now return to grass-roots programs to continue this important work.
Folks might want to take a look at what we had on it in response to Justin Gillis’ front page screed on the same in the NYT, and also click on the links to earlier articles on the upcoming IPCC fiasco:
http://www.cato.org/blog/ipcc-chooses-option-no-3
@- richardscourtney
“We are discussing the present global climate system which has been recovering from the Little Ice Age (LIA) for centuries. Any alteration to that system would be a change.”
Unfortunately in my stupidity I can see no reason WHY the present global system is ‘recovering’ from the LIA. By using the word recovering you make it sound as if the LIA was a pathological condition that the climate system had somehow acquired and it is only now managing to repair and correct itself.
The history of the Holocene is of gradual cooling since the climate optimum around 8000 years ago. Marcott et al recently produced a robust estimate of the last few thousand years of the state of the climate and it is clearly of a gradually cooling system as predicted by the physics of the Milankovitch cycles and seen in each previous interglacial period.
@-“And the recovery from the LIA seems to have been a steady rise with periods of ~30 years of warming interrupted by periods of ~30 years of lack of warming or slight cooling. There is no evidence of any kind that the climate system which is recovering from the LIA has changed; none, zilch, nada.”
So YOUR null hypothesis requires that it assumed without any reference to a cause that the climate system is recovering from previous state, and that process of change from the previous state is the null state. In fact as you claim that part of this miraculous healing or recovery performed by the anthropomorphic climate system involves ~30 years of lack of warming or slight cooling. That implies that you have chosen a definition of the null hypothesis that is incapable of refutation EXCEPT by significant cooling.
While you and Jan Kjetil Andersen spar over whether causation or only correlation/coherence can be observed, both of you have overlooked the fact that science deals in explanations supported by empiricalobservation, but invoking known physics, chemistry and biology.
Unless you can explain what this recovery from the LIA is caused by at the level of physics/chemistry/biology, it is null as a scientific explanation, merely descriptive as a hypothesis.
@-“However, on the basis of your history, I am willing to accept that your inability to understand was stupidity and not egregious.”
I thank you for the magnanimity of your condescension, and await with anticipation your explanation of why the climate system has been in a state of improving convalescence from the illness of the LIA, and how that state can be distinguished from any other physical process that might be affecting the climate system if significant cooling is the only “unprecedented climate behaviour” that would refute your selected null.
@- davidmhoffer
-Re; Data from the satellite-based Special Sensor Microwave Imager (SSM/I) show that the total atmospheric moisture content over oceans has increased by 0.41 kg/m2 per decade since 1988.
“Really? How do you stuff 0.41 kg of water into a two dimensional plane?”
It is a satellite measurement of the increase in water vapour as a result of the warming. If you were familiar with the field you would see that the satellite looks DOWN on the atmosphere and only detects the change within an area over the total depth of the atmosphere. Therefore the changes observed are expressed as changes per square metre from the TOA to surface.