By Paul C. “Chip” Knappenberger and Patrick J. Michaels
The United Nations Intergovernmental Panel on Climate Change (IPCC) is in the midst of finishing its Fifth Assessment Report (AR5) on the topic. Based on a series of content leaks, it seems as if the AR5 has so much internal inconsistency that releasing it in its current form will be a major fiasco.
The central issue of climate change science is the earth’s equilibrium climate sensitivity (ECS)—that is, how much the earth’s average surface temperature will increase as a result of a doubling the atmospheric carbon dioxide concentration. New and mutually consistent re-assessments of this important parameter are appearing in the scientific literature faster than the slow and arduous IPCC assessment process can digest them (presuming it even wants to—given that they are making the current AR5 look pretty bad).
Further, even if the IPCC is able to do an adequate job of assimilating this evolving and quite convincing science, the vast majority of the rest of the IPCC’s report will also have to be changed as it is highly dependent on the magnitude of the climate sensitivity.
By now, though, it’s too late in the game (the final report is due out in early 2014)—the cows have all left the IPCC’s barn on these subjects and it’s too late to round them all up and rebrand them.
The First Order Draft (FOD) of the IPCC’s AR5 was leaked/made public back in December 2012. In the FOD, the IPCC recognized the significance of the earth climate sensitivity, calling it:
[T]he single most important measure of climate response because the response of many other climate variables to an increase in CO2 scales with the increase in global-mean surface temperature.
The IPCC went on to assess the current scientific knowledge as to the magnitude of the climate sensitivity this way:
Despite considerable advances in climate models and in understanding and quantifying climate feedbacks, the assessed literature still supports the conclusion from AR4 [the IPCC’s Fourth Assessment Report published in 2007] that climate sensitivity is likely in the range 2–4.5°C, and very likely above 1.5°C. The most likely value remains near 3°C. An ECS greater than about 6–7°C is very unlikely, based on combination of multiple lines of evidence. [emphasis in original]
The IPCC’s “mostly likely value” in the FOD is 3.0°C. This is interesting in and of itself because according to the same First Order Draft the average climate sensitivity produced by the climate models used by the IPCC is 3.4°C, which is already some 13% higher than the IPCC’s 3.0 degrees.
If the IPCC thinks there was something systematically wrong with the models it was using, then it should just come out and say it. The fact that the IPCC (currently) will not do so does not exactly inspire confidence in its ability to stand up and criticize. In reality, the average climate sensitivity of a collection of results published within the past 2-3 years suggests that the value is closer to 2.0°C, and recent observations of the pace of global temperature rise hint at a value even a bit lower than that.
The IPCC has come under growing pressure from the scientific community—especially members of the commission directly involved in climate sensitivity research—to reflect these new, lower estimates.
There are some indications, though, that the IPCC times may be a–changing.
According to The Economist, which claims to have seen the most recent draft of the IPCC’s AR5, the IPCC’s assessment of climate sensitivity has now been altered. Here is how The Economist describes what is in the new IPCC draft concerning the equilibrium climate sensitivity:
Both the 2007 IPCC report and a previous draft of the new assessment reflected earlier views on the matter by saying that the standard measure of climate sensitivity (the likely rise in equilibrium temperature in response to a doubling of CO2 concentration) was between 2°C and 4.5°C, with 3°C the most probable figure. In the new draft, the lower end of the range has been reduced to 1.5°C and the “most likely” figure has been scrapped. That seems to reflect a growing sense that climate sensitivity may have been overestimated in the past and that the science is too uncertain to justify a single estimate of future rises.
If this is true, the combination of the IPCC lowering the low end of the range of possible climate sensitivity values and the IPCC deciding not to provide its assessment of the “most likely” value strongly suggests that the average climate model sensitivity of 3.4°C is even further removed from the science on the topic and less justifiable. Just how far removed the climate models really are is kept under wraps by the IPCC by its no longer supplying a “most likely” value. If the “most likely” value were to be assessed at 2.5°C, then the climate model average would be 36% too high compared to the science. If the “most likely” value were to be 2.0°C, then the model average climate sensitivity would be some 70% too high.
Because, as the IPCC admits, the change in many other climate variables “scales with the increase in global-mean surface temperature,” the climate impacts derived from the model projections (which essentially is what the IPCC is all about) are also (substantially) too high.
The IPCC has three options:
- Round-file the entire AR5 as it now stands and start again.
- Release the current AR5 with a statement that indicates that all the climate change and impacts described within are likely overestimated by around 50%, or
- Do nothing and mislead policymakers and the rest of the world.
We’re betting on door number 3.
On a final note, the problem of large government climate change assessments being scientifically outdated even before they are released is not atypical of “group science,” which is hugely expensive, grossly inefficient, and often is designed to justify policy. We noted the same thing in our comments on the recent draft report of the U.S. effort at assessing climate change impacts, the “National Climate Assessment” (NCA), stating:
To the extent that the recent literature ultimately produces a more accurate estimate of the equilibrium climate sensitivity than does the climate model average, it means that, in general, all of the projections of future climate change given in the NCA are, by default, some 40% too large (too rapid) and the associated (and described) impacts are gross overestimates.
Our recommendation is that an alternative set of projections be developed for all topics discussed in the NCA, incorporating the latest scientific findings on the lowered value of equilibrium climate sensitivity. Without the addition of the new projections, the NCA will be obsolete on the day of its official release.
And to think, these national and international assessments are undertaken to justify policy actions.
Scary thought.
Global mean surface temps have gone up by ‘0.8C’ since 1850. What proportion of this rise has the IPCC conceded is due to natural climate variation as we came out of the Little Ice Age? ……..Ignoring all the ‘necessary adjustments’, UHI, soot, land use changes, thermometer changes etc.
Expect a new thermometer deep ocean program where all the instruments will be placed as near to deep sea volcanic vents as necessary. The missing heat will be found. Siting issues – unverifiable. 🙂
Other_Andy says:
July 26, 2013 at 7:38 pm
Werner Brozek says:
At the moment, RSS has a flat slope for 16 years and 7 months.
hasn’t the RSS been flat before for almost that long?
1979 till 1995, or 16 years.
What’s different now?
From 1979 to 1995, or 16 years, the slope was still positive at 0.0029. Now the slope is actually very slightly negative for 16 years and 7 months. At no time has RSS been negative for that long.
In reply to:
Village Idiot says:
July 26, 2013 at 10:38 pm
What policy actions? The world community has done basically nothing to reduce GHG emissions!
Now THAT’S scary.
William:
The Western countries have most definitely done something in response to the IPCC’s scary predictions.
The Western countries have wasted trillions of dollars on scams that have made almost no difference in atmospheric CO2 emissions in the countries where the scams were installed. CO2 emissions in Western countries have increased if the CO2 content of imported goods is included. Western countries have just managed to increase the loss of manufacturing jobs to Asia.
A good example of a super duper scam is the conversion of food to biofuel which has resulted in massive deforestation and increased the price of food for all nations. The conversion of food to biofuel is madness and will result in food wars if it is not stopped.
As you note world emissions of CO2 have increased. However, if the planet resists forcing changes rather than amplifies forcing changes the warming due to a doubling of atmospheric CO2 will be less than 1C with most of the warming occurring at high latitudes which will and has caused the biosphere to expand.
Plant’s of course eat CO2 and thrive when CO2 increase. There is for example a 40% increase in cereal crop yield when CO2 doubles. When atmospheric CO2 is raised C3 plants can and do produce less stomata which enables them to reduce water loss. The reduction in plant trans-respiration water loss will and has reduced desertification and leaves more water at the plant’s roots for nitrogen fixing synergistic bacteria. Win-win for the biosphere.
It is surreal that the atmospheric increase in CO2 and the slight warming at higher latitude regions is one of the most beneficial environmental changes man is making to the environment.
The warmists are fighting the wrong war. The environmental issue is habitat not CO2 emissions. To have surplus money to spend on habitat protection and conservation countries need to be successful, to have industry, to have jobs. Cheaper energy more jobs. Wasting trillions of dollars on green scams has increased the deficit and reduced funding for all programs. The liberals do not get the concept of limited funds to spend. Indefinite deficit spending ends in tears. A series of Greece and Detroit like collapses.
The reason the warmists are fighting the wrong war is primarily the incorrect IPCC science and a lack of understanding concerning costs and engineering issues related to the green scams.
If the increase in atmospheric CO2 was truly an issue the only solution would be a massive change to nuclear power, war time like restrictions on the economies of all countries, and a massive drop in living standards in the Western countries. That type of policy ‘change’ would require military action to enforce and to get agreement from all countries. The citizens of Western democratic countries would not support the massive reduction in standard of life and a massive conversion to nuclear power.
There has been absolutely no realistic discussion of what it would take to reduce CO2 emissions by say 60% for the entire world not just for Western countries.
My view is that the atmospheric control system that damps out natural fluctuations is near 0 K CO2 climate sensitivity.
There has been AGW, from Asian aerosols reducing the albedo of low level clouds. This led to the 1980s and 1990s heating but has now saturated. It lead to the ocean temperature rise
What we are seeing now in the reduction of TPW and the turn down of OHC and air temperature is the effect of operation of other parts of the control system.
CO2 is automatically eliminated from the temperature effects.
Seems to be an urgent need to introduce an extended twelve month assessment review before releasing a failed before publication AR5! This will keep IPCC scientists scrambling for their cut of the “extended” research funds and so employed for an extra 12 months ?, or more, if luck holds and funds kept flowing it could be further extended, as they gravely ponder why the models aren’t living up to the job that was given them, a tweak here an adjustment there, and you never know what they might be able to get away with, before admitting the inevitable, that they really don’t know,…. puzzled, concerned, thus requires much more research funding!!
And unless a hiatus/pause in funding intervenes, I guess they will hope that the weather will co-operate, that mother nature serves up some super variable that can be used [exploited] to scare the pants off everyone!!
No matter what the weather will eventually do, if they can just spin it right AR5.1 might just continue the gravy train until some new scam can be developed for AR5.2.1 take three..
After all we must keep those insiders and THE INDUSTRY rewarded/paid at the level and manner to which they demand to be accustomed too, and at least until IPCC Mark II can be justified by the UN agenda commissars.
This could not happen though, no one can be that stoopid!!
Any engineer who has ever dealt with positive feedback just knows that high levels of positive feedback are highly unlikely in any real system. So, as a matter of simple common sense you would need an extraordinary argument to justify a figure even as high as 2°C. Personally I would need my arm twisted behind my back by unquestionable data and unanimous agreement by ivory tower academics to even consider a sensitivity greater than 1.5°C.
So, we know that most of what they are modelling is just chaotic natural variation which cannot be modelled except as (1/f) “noise”. And so we know these unbelievable levels of positive feedback are just the result of blind senseless curve fitting … which given the nature of noise will slowly and surely come down toward a figure below 1.5°C.
So this whole IPCC clownery is a bit like watching Men In Black for the third time … we all know exactly what is going to happen … but it is still fun to watch.
‘releasing it in its current form will be a major fiasco.’
that depends on what the update is intended to do , the chances are very good it will support the need for a IPCC, that is check one , the chances are very good it supply ‘political’ required ‘proof ‘ that is check two and the chances are there will more than enough in it for the AGW faithful to spin to their friends in the press, that is check three .
Remember they said themselves they do not do science so its ‘scientific validity ‘ is no measure of its ‘worth ‘
In other words its can be fact free nonsense that defines reality , but still be far from a ‘fiasco’ for those whose who support ‘the cause ‘
Other_Andy says:
… hasn’t the RSS been flat before for almost that long?
Werner Brozek says:
From 1979 to 1995, or 16 years, the slope was still positive at 0.0029. Now the slope is actually very slightly negative for 16 years and 7 months. At no time has RSS been negative for that long.
I’ve always loved the way the warmist zealots were incensed by the pause – to the sceptic 16 years without warming is neither here nor because ups, downs, pauses humps, valleys … these are all precisely what you expect from a system with (1/f) noise.
But to the warmist whose whole career advancement is contingent on the belief that one of these random trends was caused by us … it was the end of the world.
First they round it out … but then it got so long that any rounding that got rid of the pause also destroyed the impact of the 30 year warming trend.
So then they denied it existed “global warming has not stopped” … but Canute like the sceptical tide kept coming in.
So then they tried to explain it as “something we always expected” … but to argue that natural variation was causing the lack of warming … meant they had to stop denying the huge contribution of natural variation.
So, then they just said “but it is not cooling”.
Now it has started cooling
So lately I have seen another argument to prove themselves “right” … which is that “they always predicted climate change” … which is slowly morphing into “we always predicted natural variation” … which is just a very long and convoluted way of them using long words and lots of Greek/Latin pretend made up words to say …
The scientists were always right because science is by its very nature sceptical … so all us science plebs (obviously I joke) at WUWT were clearly by (their) definition wrong. Because now climate scientists are the sceptics.
hand me the monkey wrench!
You have contributed an excellent look into the scientific mess the IPCC has created Pat and Phil. Thank you. While we see through the bad science behind the IPCC forcing position and know that CO2 is not a pollutant or a significant green house gas, our political leaders, the media and environmentalists accept and act upon the IPCC conclusions without question. Billions of dollars flow to the IPCC scientists and their research organizations. Our scientific societies and publications debate the details but never question the concept of CO2 forcing as the culprit behind catastrophic global warming. And when we question the IPCC Report we will be dismissed as crack pots or paid pawns of the fossil fuel industry. Knowing all this, you fine gentlemen continue to work toward exposing the scinetific establishment’s folly of continuing to promote Co2 forcing. I salute you.
Alan Watt, Climate Denialist Level 7 says:
July 26, 2013 at 5:06 pm
“If the “most likely” value were to be assessed at 2.5°C, then the climate model average would be 36% too high compared to the science. If the “most likely” value were to be 2.0°C, then the model average climate sensitivity would be some 70% too high.”
I don’t think this can possibly be right. Did you reverse these two?
I think you might want to go back and re-read, Alan. The point made was, these suggested “most likely” values do not correspond to the model average of 3.4°C. The model average is 36% higher than 2.5°C, and 70% higher than 2.0°C.
Oops, I should clarify: the sensitivity of the model average is higher.
I have commented on this before. the timing of AR5 presents real problems for the IPCC.
Depending upon which data sets are used, the pause in the rise of temperature anomalies is between 16 to 22 years. The release of AR5 will coincide with the ‘magical’ 17 year period when data length is claimed to be long enough to be significant. Assuming that 2013 and early 2014 does not show any rapid rise in temperature anomalies, the report will be released coinciding with what even the proponents iof the ‘conjecture’ claim to be a significant lengthy main temperature set which shows no warming for 17 years.
Further, again assuming no significant warming in 2013/early 2014, by the time of the release of AR5, or by the beginning of 2015, the observed temperatures will below the 95% projection of even the coolest of the ensembe model runs. Within the next year or so, we will be drop out of the scenario C model projection. Just imagine the laughter if the IPCC were to present a report claiming rthat action is needed to halt dangerous warming coinciding with the time that observational temeprature records sho that the Earth’s global temperature anomaly is below that projected for a complete halt of all CO2 emissions!
It is an inescapable fact that the longer the pause in warming, the lower the Climate Sensitivity muct be. How can the IPCC release a report which does not reflect this and the fact that the latest evidence suggests a Climate Sensitivity of below 2.5deg C, if not below 2degC? As the pause in temperature anomaly rise continues there will be more and more studies suggesting low Climate Sensitivity. One can expect to see a lot iof papers between 2014 and 2017 re-assessing Climate Sensitivity more towards the low end of the IPCC’s current estimations. The fifth assessment will be consider as obviously flawed, if it becomes patently inconsistent with the latest evidence/reports on Climate Sensitivity and will be entombed in a constant battle to justify it’s position in the light of the barrage of recent studies pointing to significantly lower Climate Sensitivity.
Personally, I doubt that AR5 needs substantial re-writing. It is just the emphasis of the conclussions that need attention. They need merely to be framed in less certain terms, and need merely to accept that presently we do not know the level of Climate Sensitivity, it is inherently uncertain but the probability distribution now no longer suggests that it will be more than 3degC (or perhaps 2.8degC, or even 2.7degC, if really bold). If they want to be really bold, they can still stick to the past estimate range and state that recent studies now suggest that the probability of the distribution is such that it is unlikely to exceed 3degC, and more likely to be below 2.3degC (or may be even 2.2degC), without actually putting a figure on it.
As long as they maintain a risk that Climate Sensitivity will be more than 2degC, then they can still justify action. By emphasising probabilities they can assert that there is a not insignificant risk that Climate Sensitivity will be somewhere between 2.2degC and 3degC such that action to curb emissions is still required.
The real issue is how are they going to deal with extreme weather events, and the recent heat waves.
William Astley: “It would appear the IPCC and many of us do not believe significant cooling is possible. ”
The key word here is “significant”. This is in fact a concept born out of model of variation based on Gaussian noise. In Gaussian noise one can assign levels of “significance” as in a threshold which we not expect to be crossed by 5%, 0.01% or whatever level we choose.
However, climate variation is not Gaussian … instead it is 1/f. The difference is that a signal drifts, so there cannot be any concept of a “significant” level because the theoretical level of long term noise is infinite. So, there is no single level which is “significant”.
Instead, significance must be defined within a time period. “There is less than a y% expectation of warming/cooling of greater than X°C within a time period Z.
Gaussian noise is simple, the statistics is simple, the concepts are simple and when it can be used it is the preferred way to think of natural variation. That is why science courses tend to avoid 1/f noise, but climatic noise is not Gaussian it is a form of 1/f noise and one just cannot use “noddy” statistical ideas like “significance” that derive from Gaussian noise.
So e.g. if you ask “is significant cooling likely in the next year”, or “is significant cooling likely within the next decade/century” … you could get a sensible response from those who understand natural variation (better with a scale for that trend). But if you ask “is significant cooling possible” … the proper answer is that we expect cooling because a trend is as natural to 1/f noise as is the concept that Gaussian noise will sooner or later return to the “baseline”. So as we expect trends in 1/f noise whenever we suspect natural variation we expect to see (short term) trends so, without stating a scale or timescale, a trend is never significant.
I should perhaps have added to my above post a further problem faced by the IPCC, namely that climate is local/regional, not global.
Irrespective of what may be happening globally, much of Northern Europe is cooling. The UK, according to CET, has seen a fall in temperatures of 0.5degC since 2000. Hence in the UK there is not simply a pause in the ruise of tempeature anomaly, but a significant fall given that (it is claimed that) the 20th Century warmed by about 0.7 or 0.8degC. So most of the past century warming as been eradicated. Perhaps more significantly, as far as winter temperatures are concerned CET suggests that these have fallen by nearly 1.5deg C since 2000. The upshot of this is that people are not experiencing global warming, but rather regional cooling and this presents a PR and a political problem for ‘the Cause’.
Much of Northern has experienced similar. This is material since Europe has been one of the strongest advocates for decarbonisation. The public is gradually and slowly becoming aware of the consequences of the decarbonisation agenda, namely high energy costs causing many to face fuel poverty, and industrial uncompetitiveness creating a very slow rebound from the economic depression in Europe and a cap on wages and the risk of job losses.
All of this makes it difficult for the politicians to sell manmade global warming. The MSM is just awakening to the plight and one can therefore expect the 5th Assessment to be more openly scrutinised in the press. Should Northern Europe continue to cool and should the enrgy policies of EU states get into trouble, one can expect the IPCC to be in for a rough ride if its report is far divorced from reality.
These factors additional pile pressure on the IPCC to be more honest, if not to succumb to public ridicule. The ‘Cause’ would truly be lost if MSM were to start ridiculing the IPCC, and the next step from there, is for the press to look into the gravy train. I firmly consider the IPCC needs to have some semblence of realism in its report, and politicians themselves require this since they will be the focus of attention should the MSM start suggesting that AGW was never settled, never certain and much of it a hoax. Don’t forget that judgment will be based on hindsight. Someone will look at the thermometer record since 1850 and point out that there were periods of warming, and periods of cooling quite independent of CO2 emissions, and periods of warming and cooling are natural and to be expected when reviewing climate. They will question why anyone could have been as stupid to consider that CO2 was a mjor player.
Mike Haseler says:
July 27, 2013 at 12:11 am
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Mike
I have read your comments with interest.
If you just stop and think of what planet Earth has been through these past 4.5 billion years, and how remarkably stable the known climate is, it is almost certainly the case that there must be negative feedbacks at play.
Accordingly, if the ‘theoretical’ warming response to a doubling of CO2 is about 1.2degC, if you were to take a gut shot, I suspect that most reasonable people would consider that Climate Sensitivity must be less than 1.2degC. I am sceptical of the entire concept, but I would wish to see overwhelming evidence before I consider that I would be persuaded to accept a Climate Sensitivity figure of 1degC, or more..
Just from knowing how planet Earth has survived this long notwithstanding the fire and brimstone it has gone through, runaway global warming sounds nonsense in the extreme. All our data is flawed, much of it is not fit for the purpose to which it is being put, we have no proper grasp on natural variation and its bounds, and we do not know and understand all the feedbacks.
Other_Andy says:
July 26, 2013 at 7:38 pm
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Other_Andy
You are right, it has been flat before.
This is material, since RSS suggests that there is no first order correlation between CO2 emissions and temperature, unless the Super El Nino (in and around 1998) which coincided with the only warming (which was a step change) in its entire 33 year record was in some way driven by CO2 (which as far as I am aware, is not cliamed).
Accordingly, if one were to review the 33 year record of the Satelitte data (RSS and UAH) one would be forced to conclude that Climate Sensitivity based purely on that data appears to be zero or so close thereto that it can not be currently measured by empirical observational evidence of the resolution posssessed by the Satelitte measuring equipment.
Village Idiot says:
July 26, 2013 at 10:38 pm
Very well chosen ID. Congrats
The IPCC may well re-phrase AR5 to improve clarity for ‘decision makers’. They can hardly do an about face, but will seek to give themselves room to manoeuvre in AR6, whilst at the same time reinforcing the message that the underlying warming trend remains and will return even more strongly after a period of natural variability.
However, the very real danger exists for the IPCC that prolonged and possibly increasingly steep cooling to 2030 and beyond will leave the IPCC and their cohorts in complete dissaray.
The MSM is increasingly showing signs of deserting the sinking co2 ship with a recent UK television program bringing news about a quiet sun and a potentially cold future. I have noticed that this has had an impact on a number of people at work and it wouldn’t take a lot more to produce a sea change in public opinion, producing a significant sceptic majority amongst the voters some time before the shielded from reality politicians finally learn they have been skilfully manipulated by Green Peace, the WWF, the IPCC and other watermelon organisations.
The real question for me is how wide an area for manoeuvre will the IPCC try to create in the air brushed final release of AR5. Will they leave enough room to allow for the possibility of cooling ?
Ultimately I think the question of sensitivity to co2 forcing will be discarded as effectively irrelevant.
Might I make a suggestion concerning the “presentation” issues we have to deal with in CAGW, GW, CC or whatever it’s latest incarnation is?
The Alarmists call the current situation a “pause” (those that accept that there is a flattening of the global temperatures in the first place) which of course implies it will continue rising at some point in the future. The Met Office and Ed Davey (Minister for DECC UK) used this semantic trick formally in their recent pronouncements. We “deniers” sometimes use this phraseology as well, possibly without thinking too closely, thus appearing to go along with the meme. This has the effect of “confirming” the Alarmist message to the vast majority of the population who maybe have but a passing interest in the subject (for now) but who are the targets for the Alarmists.
There is a vast difference in perception from a MSM headline that reads “Global Warming Paused” to “Global Warming has Stopped”.
I believe that technically and semantically the warming has “stopped” (for some years now) and unless we know for certain it will continue then should that not be the word we use to describe the situation?
I am not advocating the use of tricks or untruths (the other side are our masters on that front) only that we remain wary of falling into the traps prepared for us.
I do not have a technical background and so if my understanding of the current hiatus is wrong then ignore the post.
Werner, Mike and Richard.
Thanks for the replies.
So, according to the warmists CO2 (And positive feedbacks) controls the Earth’s temperature. As CO2 goes up so does the temperature.
Between 1979 and 1996, CO2 increases by 25 ppm (More than 7% increase), there are several El Ninos and the temperature stays the same.
What is their explanation?
Then we get a huge El Nino around 1997-98, CO2 drops by 3 PPM and the temperature goes up by 0.3 C in 1997-1998 (Surprise?!).
Background: The period 1990–1994 was unusual in that El Niños have rarely occurred in such rapid succession and on top of that there was an especially intense El Niño event in 1998..
From 1999-2013, CO2 rises by 30 PPM (almost 10%) and the temperature stays the same.
And they say that CO2 (And positive feedbacks) controls the Earth’s temperature…?
I have said this before and I repeat, CO2 atmospheric residence time is far more important than the sensitivity rate. The IPCC use 100-200 years, the actual figure is between 5 and 10 years. Using the IPCC guess in models makes far more difference than doubling the CO2 content. Using the correct figure shows that our input is not significant.
Absolutely perfect. Well done.
The residence time of the average atmospheric CO2 molecule is 5 years, but the average residency time of increased CO2 levels in the atmosphere is 100 to 200 years. There is a difference in the concepts although they use the same term, residency.
Although a new study released in Nature Climate Change yesterday said the CO2 level residency time is more like 300,000 years. There is another term, weathering, which geologists have used successfully for a long time, but when the term is transferred to climate science, all kinds of unbelievable results pop out of the models used by the warmers.
Temps are currently rising as though the CO2 sensitivity per doubling is 1.2C to 1.4C.
By the year 2100, CO2 levels will likely be higher than the straight doubling level so tack on another 0.3 to 0.4C for temperatures by the year 2100. The log relationship of temperatures to CO2 will then keep temps close to stable even with increased CO2 after the year 2100.
But climate science also has control of the observational data. There are many years available to adjust the historic temperature records by the year 2100. They could get it up to 3.0C at the rate they are adjusting it currently.
To be honest, I think the temperature adjustments have kept them in the game for now. Without the adjustments, IPCC AR5 might never have happened or maybe it would have just been a wrap-up report, noting that temps will rise but it will not be a significant problem.
This science is going to be around for a long time unless we get the warmers out of the business of also controlling the temperature history.
Chad Wozniak says:
July 26, 2013 at 9:39 pm
@Ian W –
I wouldn’t be too sure that the worldwide focus is shifting away from CAGW, or that it will do so very soon.
Perhaps I was not clear.
The ‘useful idiots’ and fame seekers in climate ‘science’ have done their job and are now of no further use to the politicians. there is no continuing political requirement for the IPCC and the climate ‘science’ coterie as the ‘science is settled’ and the efforts now move forward along the Common Purpose of implementing Agenda21.