What Do We Think About Climate Change

[Boston]

Pardon me but Im a bit skeptical about this Ferenc guys work on climate

Wasn't old Ferenc the guy who's last paper was blasted by the scientific community or its numerous errors and formula's that simply did not add up. Eq 4 to be specific of his last ?

Just sayin cause now it kinda looks like he is at it again with this new paper

Although at least he has admitted that there is warming he is also suggesting that he could not find a cause and pretty much focuses on the denial end of it by focusing on what he thinks its not rather than presenting what he thinks it is. Kinda odd for a paper to rather then present an idea try and shoot one down wouldn't you think.

should be interesting to see what the community has to say about this new work by Miskolczi cause there is this little bird telling me something is amiss in his calculations which someone more qualified and with more time than I is just waiting to publish.

should be interesting to do a quick search and see if there are any responses to this paper yet

just to review we know his last paper (2007) was completely off base

1. The whole theme of the analysis as something that undermines current AGW practice is wrong. Dr Miskolczi’s modelling is of a gray-body atmosphere (no spectral lines or shapes). No GCM or practical climate study would use such an assumption, or use any gray-body theory due to Milne. A gray-body model is sometimes used for teaching purposes to convey concepts.

2. The paper is presented as a physics-based theoretical analysis. It is based on three fundamental errors: a. Kirchhoff’s Law, which is completely mis-stated. KL says that emissivity equals absorptivity. These are coefficients, which are used with other environment variables (temperature, incident radiation) to determine actual emittances and absorbances (total energy amounts). Dr Miskolczi simply assumes the emittances and absorbances can be equated. b. The Virial Theorem. People who know about this scratch their heads here, because it is a principle which can be important in stars, but applied to Earth just describes the hydrostatic balance of the atmosphere. Dr Miskolczi’s statement is totally mystifying - he says that because of some relation between energies, two fluxes must have a certain relation. No-one can work that out. c. A third equation, (7) in the paper and on this site. Dr Miskolczi has two equations which describe the result of applying conservation of energy to the Earth and the atmosphere, the two entities in his simple model. In the paper he introduced (7) as a third, but never said over what entity or region energy balance was being assessed. In an earlier version of this on-line “proof”, he sought to invoke conservation of momentum instead - a different principle, and very strange in the context. In this latest version, it sounds like it’s back to energy conservation, but eq (7) still makes no sense.

So with the physics not really working so well, he (or Zagoni) says now on this site “Regardsless of the names and laws referred to in their derivation, the equations of Dr Miskolczi given in the points 3.-9. above are original and proved to be valid.”

3. So the proof is now, presumably, held to be empirical. But what does empirical mean here? In the paper, Dr M makes frequent reference to plots of 228 points, which seem to have reasonable regression fits. But what are the points? He sometimes talks of (”selected” radiosonde readings, but there isn’t much detail offerred. And sometimes of simulations, using his code “HartCode”. In this site he assembles the results to prove the main principles, but the claim to their observational nature is somewhat undermined by the fact that he has similar graphs for Mars. It seems clear the results are simulations - how real-world observations fit in is quite unclear.

The key finding, often quoted, is that the greenhouse effect is limited. This result follows from his claim that the optical depth has a theoretical value (about 1.84), so if more CO2 is put into the atmosphere, somehow water is squeezed out. But that theoretical depth is based on a claim that the atmosphere must somehow optimise cooling, which he never justifies. Towards the end of this “proof” site, he lists comments from some of the referees of journals that rejected his paper. I don’t know why; the referees seem to make very strong points. On this particular point, one said: ”The overall concluding statement that ‘the existence of a stable climate requires a unique surface upward flux density and a unique optical depth of 1.841’ makes absolutely no sense at all. An atmosphere can be in stable radiative equilibrium for any LW optical depth, but the equilibrium surface temperature will monotonically depend on the value of the optical depth….” Quite right - the radiative balance can’t remove or add gases to the atmosphere.

and that he refused to print a retraction to correct any of the numerous errors it contained

so now he is presenting another paper and we are supposed to take it to heart ?

[Boston]

It might also be noteworthy to realize that the Theory of Rapid Global Climate Shift began with and has continued with predictions that have turned out to be accurate enough to show that we have a working theory and not simply a few flawed models as the deniers would have you believe

from
http://www.realclimate.org/index.php...gilbert-plass/

Gilbert Plass was one of the pioneers of the calculation of how solar and infrared radiation affects climate and climate change. In 1956 he published a series of papers on radiative transfer and the role of CO2, including a relatively ‘pop’ piece in American Scientist. This has just been reprinted (as an abridged version) along with commentaries from James Fleming, a historian of science, and me. Some of the intriguing things about this article are that Plass (writing in 1956 remember) estimates that a doubling of CO2 would cause the planet to warm 3.6ºC, that CO2 levels would rise 30% over the 20th Century and it would warm by about 1ºC over the same period. The relevant numbers from the IPCC AR4 are a climate sensitivity of 2 to 4.5ºC, a CO2 rise of 37% since the pre-industrial and a 1900-2000 trend of around 0.7ºC. He makes a lot of other predictions (about the decrease in CO2 during ice ages, the limits of nuclear power and the like), but it’s worth examining his apparent prescience on these three quantitative issues. Was he prophetic, or lucky, or both?

To understand if Plass should get full credit, we need to see his workings. These are mainly outlined in two more technical papers in Tellus and QJRMS earlier that year. In today’s parlance, Plass calculated the change in top-of-the-atmosphere (TOA) radiative fluxes given a doubling (or a halving) of CO2 while everything else stayed the same. He then took that number and using someone else’s estimate of the sensitivity of the TOA radiation to the surface temperature, he calculated the temperature change that would be necessary to compensate. Converting from the units he used, the radiative flux values for a doubling of CO2 were 8.3 W/m2 and 5.8 W/m2 for clear-sky (no clouds) and averagely cloudy conditions (all-sky) respectively (and slightly larger and of opposite sign for a halving). The sensitivity of the TOA flux to surface temperature he used was around 2.3 W/m2 per ºC (equivalent to a temperature sensitivity of 0.4 ºC/(W/m2)). However, this is a ‘no-feedback’ estimate (allowing only the surface temperature to change with a constant lapse rate, but with no changes to water vapour, albedo or clouds).

Today, our current best guess for the forcing due to 2xCO2 is around 4 W/m2, and the ‘no-feedback’ sensitivity is around 0.3 ºC/(W/m2), giving an expected no-feedback temperature change of about 1.2 ºC, a factor of 3 smaller than the number Plass quoted, though since our number is for ‘all sky’ conditions, it would be a little better to compare it to his averagely cloudy number 2.5 ºC (so a factor of two higher). Note that Plass was a little casual in how he described his numbers and the ‘clear sky’ designation for the 3.6ºC number was not always made clear. However, Plass was well aware that the ‘no-feedback’ case was unrealistic and estimated that the water vapour, cloud and ice-albedo feedbacks would be amplifying, although he was not able to quantify them.

Moving now to the rate of change of CO2 in the atmosphere, Plass made a very good estimate as to how much human emissions of CO2 were increasing. His estimate was (again, in modern units) that then-current emissions were 1.5 GtC based on earlier estimates from Callendar, which actually was an underestimate. Our current best estimate for the anthropogenic emissions in 1956 is about 2.2 GtC. Given the increasing nature of the emissions, Plass then estimated that concentrations would rise about 30% by the end of the 20th Century. This however needs an estimate of how much of the emissions would be absorbed by the oceans and biosphere. Here, Plass has another impressive insight that the ocean chemistry would prevent quick uptake of the human CO2, a concept that wasn’t fully worked out until Revelle and Suess’s paper in 1957 (though possibly he may have been aware of some informal communications earlier). Plass actually assumed that none of the CO2 would be taken up in the short term. So his 30% growth estimate (the actual rise was 36%) was derived from an underestimate in emissions (and emissions growth) combined with an overestimate of the ‘airborne fraction’ (which is roughly 40% of total emissions).

Finally, his estimate of temperature rise of about 1ºC by the end of century follows from the two previous numbers, along with two further assumptions – that the climate is always close to equilibrium with the forcings and that of course, there aren’t any other factors changing. The first assumption affected by the substantial lag in the system because of the thermal inertia of the oceans, and of course, there are many more factors driving climate change over the 20th C. Plass can of course be forgiven for not knowing about the greenhouse impact of rises in CH4, N2O and CFCs (not realised until 1974), or the role of aerosol emissions (1970s), and indeed, he was fortunate that the net effect of all non-CO2 drivers is close to zero (though with significant uncertainties).

So Plass was correct about all of the big issues, but lucky that, in his quantitative estimates, the errors went both ways and end up pretty much cancelling out.

Eli has described this using Isaiah Berlin’s Hedgehog and the Fox metaphor – Plass being the Hedgehog who knows one big thing, and for whom the details are more incidental. I think this is a reasonable take, as long as it is realised that Hedgehogs are not always right, even though in this case he was.

The Fox in this case was another big name in atmospheric physics, Lewis Kaplan. He published a counter to Plass’s 1956 work in Tellus in 1960 (vol. 12, p204-208), and there was a “spirited” exchange of letters in 1961 (vol. 13, p296-302) (references for those of you with libraries – for some reason, none of the old Tellus volumes are online). His calculation used a different methodology, more up-to-date spectra but was different enough in approach and specifics to make a fair apples-to-apples comparison between the results hard to do. Nonetheless, Kaplan declared that “Plass’ estimate of a temperature drop of 3.8ºC due to a halving of [CO2] appears to be too high by a factor of two or three” and that “it would seem, then, that CO2 variations could not play a role in the ice-age cycle unless the changes were by an order of magnitude”.

The subsequent comment and reply are actually very reminiscent of recent disputes in climate science. Plass complains that not enough information was provided to replicate the analysis, that Kaplan used unjustified precision, that he wasn’t comparing like-with-like (all-sky with clear-sky), that he made unjustified technical assumptions, and that his overall conclusion was ‘misleading’ because of the neglected feedbacks (that neither of them had quantified). Kaplan responds that of course there is enough information to check his workings (in another paper), that it was Plass’ fault he compared the all-sky and clear-sky numbers, and that he has exaggerated the impact of the technical criticisms. Notably, Kaplan did not respond on the issue of feedbacks.

Looking over the exchange with a 50 year perspective, a number of things stand out. First, Kaplan does seem to have been closer to modern values in his calculation – Plass was out by a factor of two for the all-sky no-feedback case. I’m not really familiar enough with the details to be be able to tell why (perhaps someone can enlighten us in the comments). However, Kaplan was wrong about everything that has ended up mattering – CO2 does play a big role in ice age cycles (with a magnitude of change close to what Plass anticipated) and its growth today is climatically significant. Significantly, I can find no trace in the literature of any resolution of the technical issues raised in the letters. Resolution in Plass’ favour of the big questions came with further independent efforts as computers got fast enough to do the more complicated feedback problem, better observations, better spectral data and better paleo-climate information (particularly from the ice cores). In some sense, resolution of their technical differences would have been moot because that wasn’t the real issue. Of course, that would have been difficult to see at the time.

So, to summarize, Plass did have some key insights and in many respects was well ahead of his time. But he was also lucky.

[Guillermo]

Global Convergence in the Temperature Sensitivity of Respiration at Ecosystem Level
Miguel D. Mahecha,1,2,* Markus Reichstein,1 Nuno Carvalhais,1,3 Gitta Lasslop,1 Holger Lange,4 Sonia I. Seneviratne,2 Rodrigo Vargas,5 Christof Ammann,6 M. Altaf Arain,7 Alessandro Cescatti,8 Ivan A. Janssens,9 Mirco Migliavacca,10 Leonardo Montagnani,11,12 Andrew D. Richardson13
Published Online July 5, 2010
Science DOI: 10.1126/science.1189587

REPORT
"The respiratory release of CO2 from the land surface is a major flux in the global carbon cycle, antipodal to photosynthetic CO2 uptake. Understanding the sensitivity of respiratory processes to temperature is central for quantifying the climate–carbon cycle feedback. Here, we approximate the sensitivity of terrestrial ecosystem respiration to air temperature (Q10) across 60 FLUXNET sites using a methodology that circumvents confounding effects. Contrary to previous findings, our results suggest that Q10 is independent of mean annual temperature, does not differ among biomes, and is confined to values around 1.4 (±0.1). The strong relation between photosynthesis and respiration, instead, is highly variable among sites. Overall, the results partly explain a less pronounced climate–carbon cycle feedback than suggested by current carbon cycle climate models."

1 Max Planck Institute for Biogeochemistry, 07745 Jena, Germany.
2 Institute for Atmospheric and Climate Science, ETH Zürich, Universitätsstrasse 16, 8092 Zürich, Switzerland.
3 Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
4 Norsk Institutt for Skog og Landskap, N-1431 Ås, Norway.
5 Department of Environmental Science, Policy and Management, University of California, Berkeley, CA 94720, USA.
6 Agroscope ART, Federal Research Station, Reckenholzstr. 191, CH-8046 Zürich, Switzerland.
7 McMaster Centre for Climate Change, McMaster University, Hamilton, Ontario L8S 4L8, Canada.
8 European Commission, Joint Research Center, Institute for Environment and Sustainability, I-21027 Ispra, Italy.
9 Department of Biology, University of Antwerpen, Universiteitsplein 1, 2610 Wilrijk, Belgium.
10 Remote Sensing of Environmental Dynamics Laboratory, DISAT, University of Milano-Bicocca, 20126 Milano, Italy.
11 Servizi Forestali, Agenzia per l’Ambiente, Provincia Autonoma di Bolzano, 39100 Bolzano, Italy.
12 Faculty of Sciences and Technologies, Free University of Bozen-Bolzano, Piazza Università 1, 39100, Bolzano, Italy.
13 Department of Organismic and Evolutionary Biology, Harvard University, HUH, 22 Divinity Avenue, Cambridge, MA 02138, USA.

http://www.sciencemag.org/cgi/conten...ence.1189587v1

(Bolded is mine)

[Guillermo]

Further publications by Ferenc Miskolczi:

F.M. Miskolczi: Greenhouse effect in semi-transparent planetary atmospheres. Idojaras - Quarterly Journal of the Hungarian Meteorological Service, Vol. 111. No. 1. 2007.



Kratz-Mlynczak-Mertens-Brindley-Gordley-Torres-Miskolczi-Turner: An inter-comparison of far-infrared line-by-line radiative transfer models. Journal of Quantitative Spectroscopy & Radiative Transfer No. 90, 2005.



F.M. Miskolczi and M.G. Mlynczak: The greenhouse effect and the spectral decomposition of the clear-sky terrestrial radiation. Idojaras - Quarterly Journal of the Hungarian Meteorological Service, Vol.108, No. 4. 2004.



Rizzi-Matricardi-Miskolczi: Simulation of uplooking and downlooking high-resolution radiance spectra with two different radiative transfer models. Applied Optics, Vol. 41. No. 6, 2002.



F. Miskolczi-R. Rizzi: High Accuracy Skin Temperature Retrieval Using Spectral Measurements of Multichannel IR Imagers. International Radiation Symposium, Madison, Visconsin, 1998.



F.M. Miskolczi: Modeling of Downward Surface Longwave Flux Density for Global Change Applications and Comparison with Pyrgeometer Measurements. Journal of Atmospheric and Oceanic Technology, Vol. 11. No. 2, April 1994.



F.M. Miskolczi and R. Guzzi: Effect of nonuniform spectral dome transmittance on the accuracy of infrared radiation measurements using shielded pyrradiometers and pyrgeometers. Applied Optics, Vol. 32. No. 18., 1993.



F.M. Miskolczi et al.: High-resolution atmospheric radiance-transmittance code (HARTCODE). In: Meteorology and Environmental Sciences Proc. of the Course on Physical Climatology and Meteorology for Environmental Application. World Scientific Publishing Co. Inc., Singapore, 1990.

[Marco1]

Originally Posted by Boston

It might also be noteworthy to realize that the Theory of Rapid Global Climate Shift began with and has continued with predictions that have turned out to be accurate enough.....

Err...hemm...coff coff...exxxcuse mee....you mean to say the HYPOTHESIS of [insert here any name you want to use]

And predictions who have turned to be accurate? ... what? What was "predicted" that turned out to be accurate? That winter is usually cold and summer usually warm?

Come on Boston, you can claim almost anything, from polar bear extintions to the stopping of the gulf current, the melting of the ice caps and the end of the cappuccino as we know it, but "ACCURACY" in the warmers camp? You must be joking haha. I get it, its a joke, ok I get it now. Sorry a bit slow today.

[Guillermo]

Often a target for environmentalists and global warming alarmists alike, intensive modern agriculture has been demonized as the cause of many types of pollution, including those dreaded greenhouse gases. A study, appearing in the Proceedings of the National Academy of Sciences (PNAS), reveals that highly productive modern agriculture actually reduces net greenhouse gas emissions when compared with using croplands less intensively. Furthermore, expansion of agriculture, needed to feed mankind's ever growing numbers, can help reduce future increases in CO2 emissions. Looks like the doomsayers got it backwards again, more intensive agricultural is a good thing for the environment. In fact, agriculture reduced total human carbon emissions from 1850 to 2005 by 34%.

What the study found was that improved crop yields have maximized land use efficiency and minimized the need for clearing more farmland. “Enhancing crop yields is not incompatible with a reduction of agricultural inputs in many circumstances,” state the authors. “To the contrary, careful and efficient management of nutrients and water by precision farming, incorporation of crop residues, and less intensive tillage are critical practices in pursuit of sustainable and increased agricultural output.” Not that yield gains alone necessarily preclude expansion of cropland. The report suggests that agricultural intensification must be coupled with conservation and development efforts for best results. Nonetheless, continuing improvement of crop yields was found to be the most important single factor.

The report's conclusions have been corroborated by recent information from Europe. The European Commission has been working on a plan for future agricultural development. Their website states: “EU agricultural emissions of methane and nitrous oxide declined by 20.2% in the period 1990-2007. Large reductions occurred in the greatest sources of emissions, nitrous oxide from agricultural soils and methane emissions from enteric fermentation by cattle, which both fell by about 21%.” So the news from the EU is supportive.

Not only does human agriculture reduce GHG emissions today, Burney et al. suggest that in the future will reduce potential emissions even more. Benefits of intensive agriculture include reducing the need to clear tropical forests, which have been religiously defended against development by greens world wide. In view of this new work, it seems that expanding agriculture intelligently is the path to a greener future, and not an example of mankind raping the land. And, if you are worried about global warming, it looks like farming may be part of the solution, not a part of the problem.


Greenhouse gas mitigation by agricultural intensification
1. Jennifer A. Burneya,b,1,
2. Steven J. Davisc, and
3. David B. Lobella,b
Edited by G. Philip Robertson, W. K. Kellogg Biological Station, Hickory Corners, MI, and accepted by the Editorial Board May 4, 2010 (received for review December 9, 2009)

Paper here: http://www.pnas.org/content/early/20....full.pdf+html

Abstract

"As efforts to mitigate climate change increase, there is a need to identify cost-effective ways to avoid emissions of greenhouse gases (GHGs). Agriculture is rightly recognized as a source of considerable emissions, with concomitant opportunities for mitigation. Although future agricultural productivity is critical, as it will shape emissions from conversion of native landscapes to food and biofuel crops, investment in agricultural research is rarely mentioned as a mitigation strategy. Here we estimate the net effect on GHG emissions of historical agricultural intensification between 1961 and 2005. We find that while emissions from factors such as fertilizer production and application have increased, the net effect of higher yields has avoided emissions of up to 161 gigatons of carbon (GtC) (590 GtCO2e) since 1961. We estimate that each dollar invested in agricultural yields has resulted in 68 fewer kgC (249 kgCO2e) emissions relative to 1961 technology ($14.74/tC, or ~$4/tCO2e), avoiding 3.6 GtC (13.1 GtCO2e) per year. Our analysis indicates that investment in yield improvements compares favorably with other commonly proposed mitigation strategies. Further yield improvements should therefore be prominent among efforts to reduce future GHG emissions."


Supporting information: http://www.pnas.org/content/suppl/20...00914216SI.pdf

[Guillermo]

I had listed Dr. Gee in posts 1698 & 3740, but I din't dig into information about him till today. Let's see what Dr. Gee said, when, and why it is relevant (who is Dr. Gee?) to our little debate:

Geologist Dr. David Gee, chairman of the science committee of the 2008 International Geological Congress, dismissed the notion that the “science is settled” on man-made climate fears by asking his fellow scientists “How sure can we be?” about carbon dioxide driving global temperatures. “You see the carbon dioxide curve going straight across that diagram from left to right, upwards,” Gee continued.

Gee presented a temperature and carbon dioxide chart to the conference to illustrate the lack of linkage between global temperature and carbon dioxide levels. [Note: An online video of a conference climate change panel is a must-see video for anyone desiring healthy scientific debate. See:
http://www.33igc.org/coco/EntryPage....ObjectID=12520

“So my question is extremely simple, we know temperature goes up and down. We know there is tremendous amount of natural variations, but for how many years must the planet cool before we begin to understand -- we politicians and scientists-- that the planet is not warming? For how many years must cooling go on?"


David Gee
European Environment Agency, Copenhagen, Denmark

David Gee was educated in politics and economics and has worked for over 30 years at the science/policy interface of occupational and environmental risk assessment & reduction, with UK Trade Unions; the Environmental Group, Friends of the Earth, where he was Director; and, since December 1995, with the European Environment Agency, an EU information providing body in Copenhagen, where he is responsible for “Emerging Issues and Scientific Liaison” and Group leader for Science, Policy and Innovation. He has published reports and lectured on many issues, including Scientific Uncertainty,; the Precautionary Principle, Environmental Health, Environmental Taxes and Ecological Tax Reform, and Clean production/ Eco-efficiency.

Cheers.

[Boston]

a few predictions that were conservative

Back in November '09, the Copenhagen Diagnosis was published. It was basically an update on the 2007 IPCC report, comparing the data since then to the projections. The report found: (in part)

From 2007-2009, there was about 40% less Arctic summer sea ice than the IPCC predicted, far exceeding its worst-case scenarios.

Recent global average sea-level rise is about 80% more than the IPCC predicted.

Global CO2 emissions are around the highest scenarios considered by the IPCC.
http://www.copenhagendiagnosis.com/

You might not have heard about it because it was completely ignored by the mainstream media. On the other hand, the IPCC Working Group 2 (much lower profile than Working Group 1) made a minor error claiming that some Himalayan glaciers would melt by 2035 (in reality it's closer to 2050), reviewers caught the error but the editor didn't take the statement out before the deadline passed, and the story was all over the media

Since IPCC’s first report in 1990, assessed projections have suggested global average temperature increases between about 0.15°C and 0.3°C per decade for 1990 to 2005. This can now be compared with observed values of about 0.2°C per decade, strengthening confidence in near-term projections. {1.2, 3.2}

obviously there are many predictions of the IPCC that have proven themselves to be accurate if conservative and many more that are just plain right on the money and yes a few that were off the mark. Simple reality is it was right a lot more than it was wrong. Sorry but the deniers camp is way off base once again.

a little insight into the IPCC for those of you who clearly have no idea of what the IPCC actually is

Currently, a few errors –and supposed errors– in the last IPCC report (“AR4″) are making the media rounds – together with a lot of distortion and professional spin by parties interested in discrediting climate science. Time for us to sort the wheat from the chaff: which of these putative errors are real, and which not? And what does it all mean, for the IPCC in particular, and for climate science more broadly?

Let’s start with a few basic facts about the IPCC. The IPCC is not, as many people seem to think, a large organization. In fact, it has only 10 full-time staff in its secretariat at the World Meteorological Organization in Geneva, plus a few staff in four technical support units that help the chairs of the three IPCC working groups and the national greenhouse gas inventories group. The actual work of the IPCC is done by unpaid volunteers – thousands of scientists at universities and research institutes around the world who contribute as authors or reviewers to the completion of the IPCC reports. A large fraction of the relevant scientific community is thus involved in the effort. The three working groups are:

Working Group 1 (WG1), which deals with the physical climate science basis, as assessed by the climatologists, including several of the Realclimate authors.

Working Group 2 (WG2), which deals with impacts of climate change on society and ecosystems, as assessed by social scientists, ecologists, etc.

Working Group 3 (WG3) , which deals with mitigation options for limiting global warming, as assessed by energy experts, economists, etc.

Assessment reports are published every six or seven years and writing them takes about three years. Each working group publishes one of the three volumes of each assessment. The focus of the recent allegations is the Fourth Assessment Report (AR4), which was published in 2007. Its three volumes are almost a thousand pages each, in small print. They were written by over 450 lead authors and 800 contributing authors; most were not previous IPCC authors. There are three stages of review involving more than 2,500 expert reviewers who collectively submitted 90,000 review comments on the drafts. These, together with the authors’ responses to them, are all in the public record (see here and here for WG1 and WG2 respectively).

Errors in the IPCC Fourth Assessment Report (AR4)

As far as we’re aware, so far only one–or at most two–legitimate errors have been found in the AR4:

Himalayan glaciers: In a regional chapter on Asia in Volume 2, written by authors from the region, it was erroneously stated that 80% of Himalayan glacier area would very likely be gone by 2035. This is of course not the proper IPCC projection of future glacier decline, which is found in Volume 1 of the report. There we find a 45-page, perfectly valid chapter on glaciers, snow and ice (Chapter 4), with the authors including leading glacier experts (such as our colleague Georg Kaser from Austria, who first discovered the Himalaya error in the WG2 report). There are also several pages on future glacier decline in Chapter 10 (“Global Climate Projections”), where the proper projections are used e.g. to estimate future sea level rise. So the problem here is not that the IPCC’s glacier experts made an incorrect prediction. The problem is that a WG2 chapter, instead of relying on the proper IPCC projections from their WG1 colleagues, cited an unreliable outside source in one place. Fixing this error involves deleting two sentences on page 493 of the WG2 report.

Sea level in the Netherlands: The WG2 report states that “The Netherlands is an example of a country highly susceptible to both sea-level rise and river flooding because 55% of its territory is below sea level”. This sentence was provided by a Dutch government agency – the Netherlands Environmental Assessment Agency, which has now published a correction stating that the sentence should have read “55 per cent of the Netherlands is at risk of flooding; 26 per cent of the country is below sea level, and 29 per cent is susceptible to river flooding”. It surely will go down as one of the more ironic episodes in its history when the Dutch parliament last Monday derided the IPCC, in a heated debate, for printing information provided by … the Dutch government. In addition, the IPCC notes that there are several definitions of the area below sea level. The Dutch Ministry of Transport uses the figure 60% (below high water level during storms), while others use 30% (below mean sea level). Needless to say, the actual number mentioned in the report has no bearing on any IPCC conclusions and has nothing to do with climate science, and it is questionable whether it should even be counted as an IPCC error.

Some other issues

African crop yields: The IPCC Synthesis Report states: “By 2020, in some countries, yields from rain-fed agriculture could be reduced by up to 50%.” This is properly referenced back to chapter 9.4 of WG2, which says: “In other countries, additional risks that could be exacerbated by climate change include greater erosion, deficiencies in yields from rain-fed agriculture of up to 50% during the 2000-2020 period, and reductions in crop growth period (Agoumi, 2003).” The Agoumi reference is correct and reported correctly. The Sunday Times, in an article by Jonathan Leake, labels this issue “Africagate” – the main criticism being that Agoumi (2003) is not a peer-reviewed study (see below for our comments on “gray” literature), but a report from the International Institute for Sustainable Development and the Climate Change Knowledge Network, funded by the US Agency for International Development. The report, written by Morroccan climate expert Professor Ali Agoumi, is a summary of technical studies and research conducted to inform Initial National Communications from three countries (Morocco, Algeria and Tunisia) to the United Nations Framework Convention on Climate Change, and is a perfectly legitimate IPCC reference.

It is noteworthy that chapter 9.4 continues with “However, there is the possibility that adaptation could reduce these negative effects (Benhin, 2006).” Some examples thereof follow, and then it states: “However, not all changes in climate and climate variability will be negative, as agriculture and the growing seasons in certain areas (for example, parts of the Ethiopian highlands and parts of southern Africa such as Mozambique), may lengthen under climate change, due to a combination of increased temperature and rainfall changes (Thornton et al., 2006). Mild climate scenarios project further benefits across African croplands for irrigated and, especially, dryland farms.” (Incidentally, the Benhin and Thornton references are also “gray”, but nobody has complained about them. Could there be double standards amongst the IPCC’s critics?)

Chapter 9.4 to us sounds like a balanced discussion of potential risks and benefits, based on the evidence available at the time–hardly the stuff for shrill “Africagate!” cries. If the IPCC can be criticized here, it is that in condensing these results for its Synthesis Report, important nuance and qualification were lost – especially the point that the risk of drought (defined as a 50% downturn in rainfall) “could be exacerbated by climate change”, as chapter 9.4 wrote – rather than being outright caused by climate change.

Trends in disaster losses: Jonathan Leake (again) in The Sunday Times accused the IPCC of wrongly linking global warming to natural disasters. The IPCC in a statement points out errors in Leake’s “misleading and baseless story”, and maintains that the IPCC provided “a balanced treatment of a complicated and important issue”. While we agree with the IPCC here, WG2 did include a debatable graph provided by Robert Muir-Wood (although not in the main report but only as Supplementary Material). It cited a paper by Muir-Wood as its source although that paper doesn’t include the graph, only the analysis that it is based on. Muir-Wood himself has gone on record to say that the IPCC has fairly represented his research findings and that it was appropriate to include them in the report. In our view there is no IPCC error here; at best there is a difference of opinion. Obviously, not every scientist will always agree with assessments made by the IPCC author teams.

Amazon forest dieback: Leake (yet again), with “research” by skeptic Richard North, has also promoted “Amazongate” with a story regarding a WG2 statement on the future of Amazonian forests under a drying climate. The contested IPCC statement reads: “Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation; this means that the tropical vegetation, hydrology and climate system in South America could change very rapidly to another steady state, not necessarily producing gradual changes between the current and the future situation (Rowell and Moore, 2000).” Leake’s problem is with the Rowell and Moore reference, a WWF report.

The roots of the story are in two blog pieces by North, in which he first claims that the IPCC assertions attributed to the WWF report are not actually in that report. Since this claim was immediately shown to be false, North then argued that the WWF report’s basis for their statement (a 1999 Nature article by Nepstad et al.) dealt only with the effects of logging and fire –not drought– on Amazonian forests. To these various claims Nepstad has now responded, noting that the IPCC statement is in fact correct. The only issue is that the IPCC cited the WWF report rather than the underlying peer-reviewed papers by Nepstad et al. These studies actually provide the basis for the IPCC’s estimate on Amazonian sensitivity to drought. Investigations of the correspondence between Leake, scientists, and a BBC reporter (see here and here and here) show that Leake ignored or misrepresented explanatory information given to him by Nepstad and another expert, Simon Lewis, and published his incorrect story anyway. This “issue” is thus completely without merit.

Gray literature: The IPCC cites 18,000 references in the AR4; the vast majority of these are peer-reviewed scientific journal papers. The IPCC maintains a clear guideline on the responsible use of so-called “gray” literature, which are typically reports by other organizations or governments. Especially for Working Groups 2 and 3 (but in some cases also for 1) it is indispensable to use gray sources, since many valuable data are published in them: reports by government statistics offices, the International Energy Agency, World Bank, UNEP and so on. This is particularly true when it comes to regional impacts in the least developed countries, where knowledgeable local experts exist who have little chance, or impetus, to publish in international science journals.

Reports by non-governmental organizations like the WWF can be used (as in the Himalaya glacier and Amazon forest cases) but any information from them needs to be carefully checked (this guideline was not followed in the former case). After all, the role of the IPCC is to assess information, not just compile anything it finds. Assessment involves a level of critical judgment, double-checking, weighing supporting and conflicting pieces of evidence, and a critical appreciation of the methodology used to obtain the results. That is why leading researchers need to write the assessment reports – rather than say, hiring graduate students to compile a comprehensive literature review.

Media distortions

To those familiar with the science and the IPCC’s work, the current media discussion is in large part simply absurd and surreal. Journalists who have never even peeked into the IPCC report are now outraged that one wrong number appears on page 493 of Volume 2. We’ve met TV teams coming to film a report on the IPCC reports’ errors, who were astonished when they held one of the heavy volumes in hand, having never even seen it. They told us frankly that they had no way to make their own judgment; they could only report what they were being told about it. And there are well-organized lobby forces with proper PR skills that make sure these journalists are being told the “right” story. That explains why some media stories about what is supposedly said in the IPCC reports can easily be falsified simply by opening the report and reading. Unfortunately, as a broad-based volunteer effort with only minimal organizational structure the IPCC is not in a good position to rapidly counter misinformation.

One near-universal meme of the media stories on the Himalaya mistake was that this was “one of the most central predictions of the IPCC” – apparently in order to make the error look more serious than it was. However, this prediction does not appear in any of the IPCC Summaries for Policy Makers, nor in the Synthesis Report (which at least partly explains why it went unnoticed for years). None of the media reports that we saw properly explained that Volume 1 (which is where projections of physical climate changes belong) has an extensive and entirely valid discussion of glacier loss.

What apparently has happened is that interested quarters, after the Himalyan glacier story broke, have sifted through the IPCC volumes with a fine-toothed comb, hoping to find more embarrassing errors. They have actually found precious little, but the little they did find was promptly hyped into Seagate, Africagate, Amazongate and so on. This has some similarity to the CRU email theft, where precious little was discovered from among thousands of emails, but a few sentences were plucked out of context, deliberately misinterpreted (like “hide the decline”) and then hyped into “Climategate”.

As lucidly analysed by Tim Holmes, there appear to be a few active leaders of this misinformation parade in the media. Jonathan Leake is carrying the ball on this, but his stories contain multiple errors, misrepresentations and misquotes. There also is a sizeable contingent of me-too journalism that is simply repeating the stories but not taking the time to form a well-founded view on the topics. Typically they report on various “allegations”, such as these against the IPCC, similar to reporting that the CRU email hack lead to “allegations of data manipulation”. Technically it isn’t even wrong that there were such allegations. But isn’t it the responsibility of the media to actually investigate whether allegations have any merit before they decide to repeat them?

Leake incidentally attacked the scientific work of one of us (Stefan) in a Sunday Times article in January. This article was rather biased and contained some factual errors that Stefan asked to be corrected. He has received no response, nor was any correction made. Two British scientists quoted by Leake – Jonathan Gregory and Simon Holgate – independently wrote to Stefan after the article appeared to say they had been badly misquoted. One of them wrote that the experience with Leake had made him “reluctant to speak to any journalist about any subject at all”.

Does the IPCC need to change?

The IPCC has done a very good job so far, but certainly there is room for improvement. The review procedures could be organized better, for example. Until now, anyone has been allowed to review any part of the IPCC drafts they liked, but there was no coordination in the sense that say, a glacier expert was specifically assigned to double-check parts of the WG2 chapter on Asia. Such a practice would likely have caught the Himalayan glacier mistake. Another problem has been that reports of all three working groups had to be completed nearly at the same time, making it hard for WG2 to properly base their discussions on the conclusions and projections from WG1. This has already been improved on for the AR5, for which the WG2 report can be completed six months after the WG1 report.

Also, these errors revealed that the IPCC had no mechanism to publish errata. Since a few errors will inevitably turn up in a 2800-page report, obviously an avenue is needed to publish errata as soon as errors are identified.

Is climate science sound?

In some media reports the impression has been given that even the fundamental results of climate change science are now in question, such as whether humans are in fact changing the climate, causing glacier melt, sea level rise and so on. The IPCC does not carry out primary research, and hence any mistakes in the IPCC reports do not imply that any climate research itself is wrong. A reference to a poor report or an editorial lapse by IPCC authors obviously does not undermine climate science. Doubting basic results of climate science based on the recent claims against the IPCC is particularly ironic since none of the real or supposed errors being discussed are even in the Working Group 1 report, where the climate science basis is laid out.

To be fair to our colleagues from WG2 and WG3, climate scientists do have a much simpler task. The system we study is ruled by the well-known laws of physics, there is plenty of hard data and peer-reviewed studies, and the science is relatively mature. The greenhouse effect was discovered in 1824 by Fourier, the heat trapping properties of CO2 and other gases were first measured by Tyndall in 1859, the climate sensitivity to CO2 was first computed in 1896 by Arrhenius, and by the 1950s the scientific foundations were pretty much understood.

Do the above issues suggest “politicized science”, deliberate deceptions or a tendency towards alarmism on the part of IPCC? We do not think there is any factual basis for such allegations. To the contrary, large groups of (inherently cautious) scientists attempting to reach a consensus in a societally important collaborative document is a prescription for reaching generally “conservative” conclusions. And indeed, before the recent media flash broke out, the real discussion amongst experts was about the AR4 having underestimated, not exaggerated, certain aspects of climate change. These include such important topics as sea level rise and sea ice decline (see the sea ice and sea level chapters of the Copenhagen Diagnosis), where the data show that things are changing faster than the IPCC expected.

Overall then, the IPCC assessment reports reflect the state of scientific knowledge very well. There have been a few isolated errors, and these have been acknowledged and corrected. What is seriously amiss is something else: the public perception of the IPCC, and of climate science in general, has been massively distorted by the recent media storm. All of these various “gates” – Climategate, Amazongate, Seagate, Africagate, Guillermogate :-), etc., do not represent scandals of the IPCC or of climate science. Rather, they are the embarrassing battle-cries of a media scandal, in which a few journalists have misled the public with grossly overblown or entirely fabricated pseudogates, and many others have naively and willingly followed along without seeing through the scam. It is not up to us as climate scientists to clear up this mess – it is up to the media world itself to put this right again, e.g. by publishing proper analysis pieces like the one of Tim Holmes and by issuing formal corrections of their mistaken reporting. We will follow with great interest whether the media world has the professional and moral integrity to correct its own errors.

PS. A new book by Realclimate-authors David Archer and Stefan Rahmstorf critically discussing the main findings of the AR4 (all three volumes) is just out: The Climate Crisis. None of the real or alleged errors are in this book, since none of those contentious statements plucked from the thousands of pages appeared to be “main findings” that needed to be discussed in a 250-page summary.

PPS. Same thing for Mike’s book Dire Predictions: Understanding Global Warming, which bills itself as “The illustrated guide to the findings of the IPCC”. Or Gavin’s “Climate Change: Picturing the Science” – which does include a few pictures of disappearing glaciers though!

[Marco1]

Sea level in the Netherlands: The WG2 report states that “The Netherlands is an example of a country highly susceptible to both sea-level rise and river flooding because 55% of its territory is below sea level”. This sentence was provided by a Dutch government agency – the Netherlands Environmental Assessment Agency, which has now published a correction stating that the sentence should have read “55 per cent of the Netherlands is at risk of flooding; 26 per cent of the country is below sea level, and 29 per cent is susceptible to river flooding”. It surely will go down as one of the more ironic episodes in its history when the Dutch parliament last Monday derided the IPCC, in a heated debate, for printing information provided by … the Dutch government. In addition, the IPCC notes that there are several definitions of the area below sea level. The Dutch Ministry of Transport uses the figure 60% (below high water level during storms), while others use 30% (below mean sea level). Needless to say, the actual number mentioned in the report has no bearing on any IPCC conclusions and has nothing to do with climate science, and it is questionable whether it should even be counted as an IPCC error.

What a load of crook. Who cares what the origin of the misinformation is? The only thing that matters is its intended use.
That data, was used to "demonstrate" that oceans are rising. They could as well say that Sydney Opera House is at risk of flooding from rising seas. The fact of the matter is that oceans are NOT rising and have never been rising in any significant way other than how they have been rising and falling for centuries or rather millennia. Some of the land on our planet on the other side is sinking and may be worth mentioning that some land is rising.

Not that reality has any grip on warmist of course. We are in the coldest winter in the last 60 years in Sydney. New York is in a heat wave. Uhuuu global warming will blow us all away.

[Guillermo]

Well, Realclimate opinions on IPCC are not the most imparcial ones, I'm afraid. And I wouldn't say Copenhagen summit was precisely a success....

[Boston]

oh thats brilliant

and you actually expect ten guys to print up 3000 pages of reports by 450 lead authors as well as 800 or so contributing authors as well as govern three stages of review involving 2,500 reviewers who add something like 90,000 comments to the drafts, to actually catch every single error.

I think the readers can clearly see for themselves how completely ridiculous it is to blame the IPCC for the occasional mistake let alone blame them for the occasional error by someone else involved

sorry but you guys are nipping at heals rather than address the simple reality that the science is dam sound

In some media reports the impression has been given that even the fundamental results of climate change science are now in question, such as whether humans are in fact changing the climate, causing glacier melt, sea level rise and so on. The IPCC does not carry out primary research, and hence any mistakes in the IPCC reports do not imply that any climate research itself is wrong. A reference to a poor report or an editorial lapse by IPCC authors obviously does not undermine climate science. Doubting basic results of climate science based on the recent claims against the IPCC is particularly ironic since none of the real or supposed errors being discussed are even in the Working Group 1 report, where the climate science basis is laid out.

To be fair to our colleagues from WG2 and WG3, climate scientists do have a much simpler task. The system we study is ruled by the well-known laws of physics, there is plenty of hard data and peer-reviewed studies, and the science is relatively mature. The greenhouse effect was discovered in 1824 by Fourier, the heat trapping properties of CO2 and other gases were first measured by Tyndall in 1859, the climate sensitivity to CO2 was first computed in 1896 by Arrhenius, and by the 1950s the scientific foundations were pretty much understood.

Do the above issues suggest “politicized science”, deliberate deceptions or a tendency towards alarmism on the part of IPCC? We do not think there is any factual basis for such allegations. To the contrary, large groups of (inherently cautious) scientists attempting to reach a consensus in a societally important collaborative document is a prescription for reaching generally “conservative” conclusions. And indeed, before the recent media flash broke out, the real discussion amongst experts was about the AR4 having underestimated, not exaggerated, certain aspects of climate change. These include such important topics as sea level rise and sea ice decline (see the sea ice and sea level chapters of the Copenhagen Diagnosis), where the data show that things are changing faster than the IPCC expected.

Overall then, the IPCC assessment reports reflect the state of scientific knowledge very well. There have been a few isolated errors, and these have been acknowledged and corrected. What is seriously amiss is something else: the public perception of the IPCC, and of climate science in general, has been massively distorted by the recent media storm. All of these various “gates” – Climategate, Amazongate, Seagate, Africagate, Guillermogate :-), etc., do not represent scandals of the IPCC or of climate science. Rather, they are the embarrassing battle-cries of a media scandal, in which a few journalists have misled the public with grossly overblown or entirely fabricated pseudogates, and many others have naively and willingly followed along without seeing through the scam. It is not up to us as climate scientists to clear up this mess – it is up to the media world itself to put this right again, e.g. by publishing proper analysis pieces like the one of Tim Holmes and by issuing formal corrections of their mistaken reporting. We will follow with great interest whether the media world has the professional and moral integrity to correct its own errors.

[Marco1]

Originally Posted by Guillermo

Well, Realclimate opinions on IPCC are not the most imparcial ones, I'm afraid. And I wouldn't say Copenhagen summit was precisely a success....

Guillermo, I think it is high time you post a good tried out paella recipe.

[Boston]

might just be
cause clearly the views being expressed concerning the science of climate research are hardly informed ones


for instance

can any of you actually name these ten guys in charge of your alleged conspiracy to rule the world through carbon credits
and better yet can you trace this mythical conspiracy back for us so we can see how the science has been corrupted
feel free to begin in 1824 with Fourier's work and continue with Tyndall and Arrhenius

its a ludicrous suggestion that this is some kind of gigantic conspiracy

[Marco1]

PS
Use normal print or it will not fit in my paella

[powerabout]

I heard from a guy working on a very large desalination plant that they have considered a falling sea level due to the drying up of many rivers and the sea going down as everybody is help bent on desal for fresh water and recycling so sewerage no longer goes into the sea and with the planet warming will make more places humid so hence more moisture carried in the air.