Estimated CO2 Warming Cut By 65%
Submitted by Doug L. Hoffman, Resilient Earth via ICECAP
Any competent researcher involved with the science behind climate change will admit that CO2 is far from the only influence on global climate. It has long been known that short-lived greenhouse gases and black-carbon aerosols have contributed to past climate warming. Though the IPCC and their fellow travelers have tried to place the blame for global warming on human CO2 emissions, decades of lies and erroneous predictions have discredited that notion. For anyone still clinging to the CO2 hypothesis, a short perspective article on the uncertainty surrounding climate change in Nature Geoscience has put paid to that notion. It states that not only did other factors account for 65% of the radiative forcing usually attributed to carbon dioxide, but that it is impossible to accurately determine climate sensitivity given the state of climate science.
In “Short-lived uncertainty?” Joyce E. Penner et al. note that several short-lived atmospheric pollutants – such as methane, tropospheric ozone precursors and black-carbon aerosols – contribute to atmospheric warming while others, particularly scattering aerosols, cool the climate. Figuring out exactly how great the impacts of these other forcings are can radically change the way historical climate change is interpreted. So great is the uncertainty that the IPCC’s future climate predictions, which are all based on biased assumptions about climate sensitivity, are most certainly untrustworthy. As stated in the article:
It is at present impossible to accurately determine climate sensitivity (defined as the equilibrium warming in response to a doubling of atmospheric carbon dioxide concentrations) from past records, partly because carbon dioxide and short-lived species have increased together over the industrial era. Warming over the past 100 years is consistent with high climate sensitivity to atmospheric carbon dioxide combined with a large cooling effect from short-lived aerosol pollutants, but it could equally be attributed to a low climate sensitivity coupled with a small effect from aerosols. These two possibilities lead to very different projections for future climate change.
All truthful climate researchers know these facts, yet publicly the party line is that catastrophic changes are in the offing and CO2 emissions are to blame. The perspective authors argue that only by significantly changing the amounts of these other pollutants and carefully measuring the impact on global climate over a period of several decades will science be able to figure out what is going on. “Following this strategy, we will then be able to disentangle the warming and cooling contributions from carbon dioxide and short-lived pollutants, hence placing much tighter constraints on climate sensitivity, and therefore on future climate projections,” they state. See chart below, enlarged here.
And they said it was all carbon dioxide’s fault.
Most of the factors under discussion have relatively short lifetimes in the atmosphere, several less than two months. We do not know how the relative influences of these various substances (referred to by climate scientists as “species”) may change in a warming climate. It is also not clear how to reduce short-lived species under present conditions but the uncertainties in atmospheric chemistry and physics must be resolved if Earth’s environmental system is to be understood. Again quoting from the paper:
Of the short-lived species, methane, tropospheric ozone and black carbon are key contributors to global warming, augmenting the radiative forcing of carbon dioxide by 65%. Others – such as sulphate, nitrate and organic aerosols – cause a negative radiative forcing, offsetting a fraction of the warming owing to carbon dioxide. Yet other short-lived species, such as nitrogen oxides, carbon monoxide and volatile organic compounds, can modify the abundance of both the climate-warming and climate-cooling compounds, and thereby affect climate change.
Quantifying the combined impact of short-lived species on Earth’s radiative forcing is complex. Short-lived pollutants – particularly those with an atmospheric lifetime of less than two months – tend to be poorly mixed, and concentrate close to their sources. This uneven distribution, combined with physical and chemical heterogeneities in the atmosphere, means that the impact of short-lived species on radiative forcing can vary by more than a factor of ten with location or time of emission. The situation is further complicated by nonlinear chemical reactions between short-lived species in polluted areas, as well as by the interactions of clouds with aerosols and ozone. These processes add further uncertainty to the estimates of radiative forcing.
Unfortunately, climate models neither accurately deal with local effects of these pollutants nor are the complex interactions among these substances understood. That not withstanding, the report is clear – CO2 does not account for even a majority of the warming seen over the past century. If other species accounted for 65% of historical warming that leaves only 35% for carbon dioxide. This, strangely enough, is in line with calculations based strictly on known atmospheric physics, calculations not biased by the IPCC’s hypothetical and bastardized “feedbacks.”
Of course, the real reason for the feedbacks was to allow almost all global warming to be attributed to CO2. This, in turn, would open the door for radical social and economic policies, allowing them to be enacted in the name of saving the world from global warming. The plain truth is that even climate scientists know that the IPCC case was a political witch’s brew concocted by UN bureaucrats, NGOs, grant money hungry scientists and fringe activists.
Now, after three decades of sturm und drang over climate policy, the truth has emerged – scientists have no idea of how Earth’s climate will change in the future because they don’t know why it changed in the past. Furthermore, it will take decades of additional study to gain a useful understand climate change. To do this, climate scientists will need further funding. Too bad the climate science community squandered any public trust it may have had by trying to frighten people with a lie.
Be safe, enjoy the interglacial and stay skeptical. Read full post here.
Icecap Note: Whatsmore, this totally ignores the other external and internal global factors like solar, ocean multidecadal cycles related to variations in the thermohaline circulation or ocean gyres.
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Here is the paper at Nature Geosciences:
Short-lived uncertainty?
Joyce E. Penner1, Michael J. Prather2, Ivar S. A. Isaksen3,4, Jan S. Fuglestvedt4, Zbigniew Klimont5 & David S. Stevenson6
- University of Michigan, Ann Arbor, Michigan 48109-2143, USA
- University of California, Irvine, California 92697, USA
- University of Oslo, PO Box 1022, Blindern, 0315 Oslo, Norway
- Center for International Climate and Environmental Research (CICERO) Oslo, PO Box 1129 Blindern, 0318 Oslo, Norway
- International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, 2361 Laxenburg, Austria
- School of Geosciences, The University of Edinburgh, Edinburgh EH9 3JN, UK.
Correspondence to: Joyce E. Penner1 e-mail: penner@umich.edu
Abstract
Short-lived greenhouse gases and black-carbon aerosols have contributed to past climate warming. Curbing their emissions and quantifying the forcing by all short-lived components could both mitigate climate change in the short term and help to refine projections of global warming.
Earth’s climate can only be stabilized by bringing carbon dioxide emissions under control in the twenty-first century. But rolling back anthropogenic emissions of several short-lived atmospheric pollutants that lead to warming — such as methane, tropospheric ozone precursors and black-carbon aerosols — could significantly reduce the rate of climate warming over the next few decades1, 2, 3.
Henry@Yuba
As indeed they did cut my final remarks. They would never allow a link to my blogg. So what does that tell you about RealClimate?
I suspect most everyone that posts much at RC has had posts that did not make it through. I have (and I don’t even post there much). You likely never would have gotten your initial question through if they had not had an “open thread” for you to post it. I too have been criticized by Gavin for the quality of my hypothesis.
The thing is that your theories are not new or unique and that they have been gone over many times at RC. Repeats of the same claims do not make it through the censors there.
You started out with a reasonable question: “How do we know the overall (warming/cooling) effects of CO2 (in isolation) on the planet? (Show me the data).” You want to verify for yourself that “they” thought of the potential pitfalls that you have. This is reasonable and is reasonable skepticism. The thing is until you track down where the numbers came from you are premature to criticize them (this is not being skeptical). You must be willing to go to the library track down obscure paywalled sources before you can make any claims as to what they do or do not include. Start with the footnotes for the AR4.
Your “70% H20>warmer water>more water vapor>more clouds> more cooling (either through radiant energy blockage or through greater convection of latent heat)” hypothesis has been around for a long time. Currently it’s most prominent champion is Dr Roy Spencer. Spencer has his own blog and I suggest you might find support there. http://www.drroyspencer.com/ Dr Lindzen (probably the best credentialed skeptical climate scientist) published a related paper a few years about his “Iris” hypothesis that is somewhat related to this theory. It has generally been discredited in the journals however.
Back to your original question about CO2 effects (in isolation). You are right we don’t know *exactly*. We do know within a couple percentage points and the in the end that is good enough because of the feedback effects of water vapor and clouds are so great. This point came up in the recent Scientific American article about Dr. Judy Curry. If you have some time it is worth a read since it is basically about the problems of political polarity in the climate issue – something you seem to be affected by as much as anyone. http://www.scientificamerican.com/article.cfm?id=climate-heretic
“What does that tell you about RC?”
It tells me that they think your hypothesis is raw and green and lacks credible scientific backing. (I would have warned you not to post it there but to limit your posts key technical questions concerning it). It really has been addressed there many times and would likely come up in most every thread if they did not censure the topic. Seriously, if you want to pursue it – first read the “feedback and forcing thread” at RC (and the following discussion) and limit yourself to key technical questions concerning it (unfortunately I suspect that thread is long closed, but I bet they would let an articulate question through from you in the open thread if it were about some aspect of the topic that was unclear or not addressed in the feedback & forcing thread). If what you want is the scientist’s response to technical questions (that is what you were asking originally) then RC is a good place for it, if you want to post your musings or links to them, then RC is not.
dear Yuba
you really have to take some time to look at the overall picture. I had my brother here from Holland and we had some long late night discussions. I remember telling him about Al Gore and his stories (the so-called glove that”fits”, :::but remember: smoking causes cancer but cancer does not cause smoking). Then I told him about actual global warming: 0.7 C during the past 100 years and that what is projected into the future (worst case scenario): ca. 1 C at the end of the next 50 years. Then I asked him if he was worried about that? (Generally in the NH they would love to have it a bit warmer). So we laughed and laughed, and laughed…..
Henry,
I have and continue to look at the big picture.
Consider that the 1C in 50 years is a global average and that it is expected to be more or less in various areas. Consider that the effects on rainfall changes are also considered to be very (if not more) significant. Consider that the effects of the Business As Usual scenario that forecasts a >1C change in the following 50 years.
Henry, I don’t want to argue how we should discount future generations. I have tried very hard to present you with sources that would both support and challenge your hypothesis. I have seen little evidence that you have followed through with questioning your and your brother’s own gut feelings (beyond your posting at RC – but then again you were very quick to play the “look – they censored me at RC” card, which is little evidence of anything in particular).
The fact that you start out with a reasonable scientific question and then resort to a “me and my brother” comment is not encouraging me to think that you are looking for a valid scientific discussion, but that you are looking for any evidence at all, no mater how indirect or valid, that will support your hypothesis (which itself is far from new).
The science is indeed complex and if you can poke a hole in it I wish you all the best, but it takes more than hand waving some wavelengths around. That is why I presented you with so many sympathetic sources. You can’t go to RC with hypothesis however; you have to have to be at least a theory and you have to be able to discuss its scientific support.
Henry, I respect your patience. I sincerely wish you and yours all the best.
Yuba, I am finished with my investigations. Look carefully at the point where I started doubting that global warming is an unnatural problem. Study those graphs in my blogg that show there have been many warm periods in the past. Why would the current warm period be different to the natural warmer! period 1000 years ago?
And what about all the periods in the past where it was warmer still? It is not up to me to provide test results of the cooling and warming properties of the CO2, O2 and H2O, and to determine their interactions, overlaps and differing concentrations. But I can antipicate that it must be near impossible to do any accurate testing or calculations if you do not even know the exact total water vapor concentration in the atmosphere.
It is people like Al Gore, M.Mann, Spencer Weart and Grant Petty who make the claims that the warming is man made due to the CO2 increase to come up with that evidence. But when you ask those people directly you find they do not have the answers. They always do know that somebody has got the results. It is hidden in sonewhere, in copyrighted papers. But when I looked carefully at the IPPC report (2005) I found they rely heavily on the assumption that they know 100% for sure what is causing the warming (i.e. more greenhouse gases) because what they did is take the year 1750 as a zero point for the gases in the atmosphere as being before the industrial revolution started. Then they looked at the increases in the various gases versus the actual observed warming and then they allocated or correlated the forcings of each GHG. But that is looking at a solution for a problem from the wrong end. This is the worst mistake a scientist can make.
Based on my further observations (various tipping points around 2003, also in earth’s albedo), I predict global cooling for the future, not global warming, especially for the next 6- 7 years.
Unfortunately I am not good at maths. But you are welcome to take on those guys with their maths. In the end you will also find what I found. It is going to get cooler. Enjoy the global warming while it lasts.
Blessings!
Henry
Don’t miss this!
http://wattsupwiththat.com/2010/10/30/new-peer-reviewed-paper-says-there-appear-to-have-been-periods-of-ice-free-summers-in-the-central-arctic-ocean/#more-27209
Well Henry, It’s obvious that you only select the information that agrees with what you want to find and discard the rest. The article you wrote about CO2 is filled with so many long debunked talking points and tenuous leaps of logic that it is clearly pointless to discuss it with you. I don’t know what 2005 IPCC report you refer to but it would appear that you haven’t spent much time with their latest 2007 report which devotes many pages to discussing uncertainty, and I don’t recall any major area of discussion that was assigned 100% certainty. I find it curious that you consider yourself such an expert on IPCC methodology when you actually seem so unfamiliar with the report (and appear to wish to remain so).
Concerning the Jakobsson et al paper; I wouldn’t draw any conclusions until I had read it, or at least read more than the abstract. I don’t find it all that surprising though since best evidence indicates that the climate has cooled over the last 10,000 years (if ever so slightly), and we also know other factors such as changes in regional wind patterns can have dramatic short term effects on the arctic ice cover.
Sorry Yuba, but clearly:
1) we have no evidence that CO2 is warming more than it is cooling
2) we know that CO2 increases as it gets warmer (remember the first smoke from a kettle).
3) We have clear evidence that these increases in CO2 in the atmosphere lagged the warming periods by quite a few hundred years.
4) We have clear evidence that warmer periods have been around due to natural causes, e.g
http://wattsupwiththat.com/2009/12/09/hockey-stick-observed-in-noaa-ice-core-data/
Did you study these graphs? There are other sources if you don’t trust WUWT…
Ergo, the conclusion is that global warming is most probably not caused by an increase in carbon dioxide.
Anyways, yes, the saying goes that you can take a horse to the water, but you cannot make him drink. I suppose that from each other’s point of view that applies both ways.
Henry, clearly:
1) You are denying considerable evidence and you are assuming facts that have not been substantiated.
2) Yes, CO2 levels have risen post glacial. This is well understood. It is not the cause of recent atmospheric rise in CO2 levels however so what’s your point?
3) Yes they have. The theory of Milankovitch glacial cycles relies on this CO2 level rise to provide the feedback necessary to warm the climate as much as it has. The changes of solar insolation alone cannot do it by itself (and apparently neither would water vapor feedback without the CO2 feedback).
4) We know that there were forest fires long before humans ever appeared. That doesn’t mean humans can’t cause them.
Unlike you I have spent considerable time reading opinions from both sides (and I continue to). As for the graph from Watts; why do I need to remind you that central Greenland is not “the globe” and it is well known that the two hemispheres don’t always respond in unison?
My mind is not closed and unlike you I have not stopped examining the evidence (from both sides). This is why I could provide you with the links that I did that were sympathetic to your position. I would like to see you prove your point and I would stop worrying. Your arguments so far fall very short of intriguing let alone convincing. Most of them are from ignorance. Your talking points are commonly known as “zombies” that no informed climatologist (even contrarian) would use because they have so long been shown to be untrue or irrelevant – they simply keep rising from the dead on internet sites that cater to the uninformed. If you spent much time researching these things you would know this.
I’m not sorry to tell you this and I don’t feel sorry for you. I think you are a smart guy, you’ve just got a bad case of confirmation bias.
I repeat:
1) It is not up to me to provide test results of the cooling and warming properties of the CO2, O2 and H2O, and to determine their interactions, overlaps at 14-15 um at differing concentrations. But I can antipicate that it must be near impossible to do any accurate testing or calculations without messing up something here or there. Never mind the fact that we cannot ever be sure of exactly how much water vapor floats around in the atmosphere. It up to the people who make these claims to provide this information.
2) Surely you can distinguish between cause and effect? Are you saying that Al Gore & company did not make it look like it was the other way around? Whether it was deliberate or not, I am deeply disappointed that he has (not yet) clarified it.
3) What is the ice age trap? Lucky enough there are already people like me looking into the future to provide answers when global cooling starts. An idea that I thought of is throwing black carbon dust on the snow to prevent the sun’s rays being sent back into space.
4) I am glad we agree on something…
Henry, I am well aware of cause and effect (and the difference between correlation and causation) you might want to review the role of “feedbacks” as used in climate change discussions.
Never having read or seen anything by Al Gore I don’t know what he said on the topic but since the rise of CO2 is integral with the warming at the end of the last glacial maximum, if he implied that CO2 had a role in warming of the atmosphere at that point – he was right. (An 800 year lag is not much considering it took ~10,000 years to warm up after the last glacial maximum. Such is the role of a feedback. Milankovitch cycles – changes in Northern hemisphere (land mass) insolation was the trigger).
SkepticalScience does a pretty good job of explaining the science in simple terms. http://www.skepticalscience.com/co2-lags-temperature.htm
Take care
BTW, the one answer from a Patrick 027 @ur momisugly RC did not mention the problem I foresee with the oxygen. It seems they never classified oxygen as a GHG. Although the absorption of O2 at 14-15 is very weak, the percentage oxygen is very high, so this must have an influence and may well account for most of earth’s missing radiation in the 14-15 um band. You may want to check up on that, make sure they did not “cook” the books and all that. Be faithful to the truth.