Posted 2 July 2012
"We are grateful to the editors of *Eos *for this right of reply to Corbin and Katz (Effective Strategies to Counter Campus Presentations on Climate Denial, *Eos*, 2012 July 3)*, *a * *1200-word *melange *or smørgasbord of the shop-worn logical fallacies of argument *ad populum, ad verecundiam, *and, above all, *ad hominem*." Lord Monckton rebuts claims made in a closed paper in *Eos, *a publication of the American Geophysical Union. === **Right of reply** We are grateful to the editors of *Eos *for this right of reply to Corbin and Katz (Effective Strategies to Counter Campus Presentations on Climate Denial, *Eos*, 2012 July 3)*, *a * *1200-word *melange *or smørgasbord of the shop-worn logical fallacies of argument *ad populum, ad verecundiam, *and, above all, *ad hominem*. The authors, arguing solely from consensus (*ad pop.) *among scientific experts *(ad vcd.)*,* *say without evidence that speakers like us “intend to muddy the waters with respect to climate science” *(ad hom.)*; they serially cite politicized websites and tendentious non-peer-reviewed presentations by non-climate-scientists against us as though they were authoritative *(ad vcd.)*, while omitting to cite published rebuttals (e.g. Monckton of Brenchley, 2006, 2010) to these dubious sources *(ad hom.)*; they accuse us of misrepresentation, distortion, and flawed analysis without adducing a single instance *(ad hom.)*; and they four times brand us as “climate change deniers” *(ad hom.)* – a hate-speech comparison with Holocaust denial. Because these irrational allegations are so serious, we have insisted upon this right of reply.** The authors also say we attempt to discredit their research when, as philosophers of science from al-Haytham via Huxley to Popper (1934) make clear, error-elimination by questioning of hypotheses is essential to the scientific method. They describe “strategies” to counter us – including “public displays” and “social media” – which surely belong more in the realm of political propaganda than of scientific discourse. Our argument against the Party line is that catastrophic manmade global warming has not been occurring at anything like the predicted rate; that there is no sound scientific reason to expect that it will; and that, even if it did, future adaptation would be at least an order of magnitude more cost-effective than heavy spending today. In the generation since 1990, the observed warming rate has turned out below the least estimate projected by the IPCC in that year. The models agreed with one another, but events have proven the consensus wrong. Despite rapidly-increasing CO2 concentration, there has been no statistically-significant warming for a decade and a half. The post-1950 warming rate, as the least-squares trend on the Hadley/CRU surface temperature series (HadCRUt3, 2011), is just 1.2 K/century. Yet IPCC (2007, table SPM.3 and fig. 10.26) implicitly predicts as the mean of all six emissions scenarios that Man’s influence, including an increase in CO2 concentration from 368 ppmv in 2000 to 713 ppmv by 2100, will cause 2.8 K warming by 2100 – 0.6 K previously committed, 1.5 K from CO2 emitted in this century, and 0.7 K from other greenhouse gases. This predicted (though unalarming) more-than-doubling of the post-1950 warming rate depends upon at least three implausible assumptions: that other gases augment CO2’s contribution to warming by as much as 43%; that as much as half of the warming caused by our past sins of emission has not yet come through the pipeline; and, above all, that unmeasured and unmeasurable temperature feedbacks will near-triple the small direct warming from greenhouse gases. Therefore, two-thirds of the consensus warming is based on a guess: and that is a poor basis for consensus. The first assumption lacks credibility now that methane, the most significant non-CO2 greenhouse gas we emit, has stabilized: its concentration grew by only 20 parts by billion over the past decade. The second and third assumptions imply a volatility in surface temperatures that is belied by the paleoclimate record, which – allowing for great uncertainties –indicates that absolute temperature has not fluctuated by more than 3% or 8 K either side of the mean in the past 64 million years (Scotese, 1999; Zachos *et al., *2001). That is enough to cause an ice age at one era and a hothouse Earth at another: but the inferred temperature variability is far too small to permit the closed-loop feedback gains of as much as 0.64[0.42, 0.74] that are implicit in the projected warming of 3.26[2, 4.5] K per CO2 doubling (IPCC, 2007, p. 798, box 10.2). In process engineering, where the mathematics of feedbacks adopted by climate science has its origins (see Bode, 1945; Roe, 2009), electronic circuits intended to be stable are designed to permit closed-loop gains of no more than 0.1. Given the Earth’s formidable temperature stability, the IPCC’s implicit interval of loop gains is far too close to the singularity in the feedback-amplification equation to be credible: for across that singularity, at a loop gain of 1, strongly net-positive feedback becomes as strongly net-negative. Yet the inferred paleo-temperature record shows no such pattern of violent oscillation. Empirical evidence (e.g. Lindzen and Choi, 2009, 2011; Spencer and Braswell, 2010, 2011), though hotly contested (e.g. Trenberth *et al., *2010; Dessler *et al., *2010, 2011), indeed suggests what process-engineering theory would lead us to expect: that feedbacks in the temperature-stable climate system, like those in a well-designed circuit, are at most barely net-positive and are more likely to be somewhat net-negative, consistent with a harmless continuance of the observed warming rate of the past 60 years but inconsistent with the far greater (though not necessarily harmful) warming rate predicted by the IPCC. Even if we assume *ad argumentum *(and *per impossibile*) that our unmitigated emissions will greatly accelerate the observed warming rate, the very high cost of measures intended to mitigate CO2 emissions exceeds the likely cost of climate-related damage arising from our failure to act now. To take a single topical and typical example, carbon trading in Australia will cost $10.1 bn/year, plus $1.6 bn/year for administration (Wong, 2010, p. 5), plus $1.2 bn/year for renewables and other costs, a total of $13 bn/year, rising at 5%/year, or $130 bn by 2020 at n.p.v., to abate 5% of current emissions, which represent 1.2% of world emissions (derived from Boden *et al., *2010ab). Thus the Australian measure, if it succeeded as fully as its promoters intend, would abate 0.06% of global emissions over its 10-year term. CO2 concentration would fall from a business-as-usual 410 to 409.988 ppmv by the end of the term. Forcing abated is 0.0002 W m–2; warming consequently abated is 0.00006 K; mitigation cost-effectiveness, which is the cost of abating 1 K global warming by measures of equivalent cost-effectiveness, is $2,000 tr/K. On the same basis, the cost of abating all projected warming over the ten-year life of the policy is $300 trillion, or $44,000/head, or 58% of global GDP over the period. The cost of mitigation by such measures would exceed the cost of climate-related damage consequent upon inaction by a factor of approximately 50. The very high costs of CO2 mitigation policies and the undetectable returns in warming abated imply that focused adaptation to any adverse consequences of such warming as may occur will be far more cost-effective than attempted mitigation today. CO2 mitigation strategies inexpensive enough to be affordable will be ineffective: strategies costly enough to be effective will be unaffordable. The question arises whether CO2 mitigation should any longer be attempted at all. Readers of *Eos *may now decide for themselves to what extent the unsupported attack upon our reputations by Corbin and Katz was justifiable, and whether the editors of any respectable scientific journal of opinion should ever have printed it. True science is founded not upon invective and illogic but upon reason. Lose that: lose all. *References* Bode, H.W. (1945), *Network analysis and feedback amplifier design,* Van Nostrand, New York, USA, 551 pp. Boden and Marland (2010a), *Global CO2 Emissions from Fossil-Fuel Burning, Cement Manufacture, and Gas Flaring, 1751-2007*, Carbon Dioxide Information and Analysis Center, Oak Ridge, Tennessee, USA. Boden *et al. *(2010b), *Ranking of the world's countries by 2007 total CO2 emissions from fossil-fuel burning, cement production, and gas flaring*, Carbon Dioxide Information and Analysis Center, Oak Ridge, Tennessee, USA. Dessler, A.E. (2010), A determination of the cloud feedback from climate variations over the past decade, *Science *220, 1523-1527. Dessler, A.E. (2011), Cloud Variations and the Earth’s energy budget, *Geophys. Res. Lett*. HadCRUt3 (2011), Monthly global mean surface temperature anomalies, 1850-2011, [http://www.cru.uea.ac.uk/cru/data/temperature/hadcrut3gl.txt](http://www.cru.uea.ac.uk/cru/data/temperature/hadcrut3gl.txt). IPCC (1990), *Climate Change: The IPCC Scientific Assessment (1990): Report prepared for Intergovernmental Panel on Climate Change by Working Group I, *J. T. Houghton, G.J. Jenkins and J.J. Ephraums (eds.), Cambridge University Press, Cambridge, UK, New York, NY, USA, and Melbourne, Australia. IPCC (2007), *Climate Change 2007: the Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, 2007* [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Avery, M. Tignor and H.L. Miller (eds.)], Cambridge University Press, Cambridge, United Kingdom, and New York, NY, USA. Lindzen, R.S., and Y.-S. Choi (2009), On the determination of feedbacks from ERBE data, *Geophys. Res. Lett., *36, L16705. Lindzen, R.S., and Y.-S. Choi (2011), On the observational determination of climate sensitivity and its implications, *Asia-Pacific J. Atmos. Sci., *47(4), 377-390, doi:10.1007/s13143-011-0023-x. Monckton of Brenchley, C.W. (2006), *Chuck it, Schmidt! A Science Commentary on Web Posts at Realclimate.org, *Science and Public Policy Institute, Washington, DC, USA, November. Monckton of Brenchley, C.W. (2010), *Response to John Abraham, *SPPI Reprint Series, Science and Public Policy Institute, Washington DC, USA, July 12, [http://scienceandpublicpolicy.org/images/stories/papers/reprint/response_to_john_abraham.pdf](http://scienceandpublicpolicy.org/images/stories/papers/reprint/response_to_john_abraham.pdf). Popper, K (1934), *Logik der Forschung, *rewritten 1959 by the author in English as* The Logic of Scientific Discovery*, Hutchinson, London. Roe, G. ( 2009), Feedbacks, Timescales, and Seeing Red, *Ann. Rev. Earth & Planet. Sci. *37, 93-115. Scotese, C.R., A.J. Boucot, and W.S. McKerrow (1999), Gondwanan paleogeography and paleoclimatology, *J. Afr. Earth Sci.* 28(1), 99-114. Spencer, R.W., and W.D. Braswell (2010), On the diagnosis of radiative feedback in the presence of unknown radiative forcing, *J. Geophys. Res, *115, D16109. Spencer, R.W., and W.D. Braswell (2011), On the misdiagnosis of surface temperature feedbacks from variations in Earth’s radiant-energy balance, *Remote Sensing *3, 1603-1613, doi:10.3390/rs3081603. Trenberth, K.E., J.T. Fasullo, C. O’Dell, and T. Wong (2010), Relationships between tropical sea-surface temperature and top-of-atmosphere radiation, *Geophys. Res. Lett, *37, L03702. Wong, P. (2010), *Portfolio Budget Statements 2010-11: Budget-Related Paper No. 1.4. Climate Change and Energy Efficiency Portfolio*, Commonwealth of Australia, Canberra, Australia. Zachos, J., M. Pagani, L. Sloan, E. Thomas, and K. Billups (2001), Trends, Rhythms and Aberrations in Global Climate 65 Ma to Present, *Science *292, 686-693. ─ CHRISTOPHER MONCKTON OF BRENCHLEY, Chief Policy Advisor, Science and Public Policy Institute, Washington, DC, USA; firstname.lastname@example.org.