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emissions to changes in atmospheric CO 2 since1960. The fraction of emissions retained in theatmosphere varies considerably and seems tocorrelate with ocean temperature, El Niñowarmings, and the coolings from volcanic eruptions.! Carbon dioxide sources and sinks arepoorly understood.Present carbon-cycle models rely on unknownsinks to explain recent trends. Presumably, theseadditional sinks were not operating prior toindustrialization and have emerged as aconsequence of the increasing atmosphericconcentration. In the future, will these ‘missingsinks’ amplify or diminish the human contributionto atmospheric CO 2 ?It is conventionally assumed that the differencebetween emitted anthropogenic CO 2 and themeasured increase must be absorbed in ocean, soils,and biosphere or partly buffered in the upper mixedocean. Yet there are few data to support this and theliterature talks about an unidentified ‘carbon sink’– renamed as ‘residual land sink’ [IPCC-AR4 2007,p. 26]. Recent speculation assigns this sink totropical forests.The observed increase in the seasonal change ofCO 2 concentration suggests increasing uptake by anexpanding biosphere and the upper mixed oceanbuffer. Unknown outgassing associated with awarmer ocean, changing exchange between thesurface layers and the deep ocean (where carbon islocked up for thousands of years), unknownbiosphere uptake in a warmer and wetter climate,increasing decay of biomass, as well as someoutgassing of (permafrost) soils, etc., all lead touncertainties in future values of atmospheric CO 2concentration.Less than half of the CO 2 emitted by fossil-fuelburning remains in the atmosphere; the rest isabsorbed by the ocean or incorporated by theterrestrial biosphere in roughly equal measures[Baker 2007]. In order to understand the relativerole of different parts of the terrestrial biosphere ascarbon sinks, global measurements of atmosphericCO 2 concentration must be interpreted by‘inversion’ models to determine how uptake,emission, and transport contribute to the seasonaland regional differences.Previous studies [IPCC-AR4 2007, p. 522] havesuggested there must be a strong carbon sink in theNorthern Hemisphere, and that the tropics are a netcarbon source. There is some evidence, consideredcontroversial, from detailed CO 2 data [Fan 1998]that North America is a net carbon sink [IPCC-AR42007, p. 523]. However, Stephens [2007] reportsthat global vertical distributions of CO 2 in theatmosphere are not consistent with thatinterpretation but are more consistent with modelsthat show a smaller NH carbon sink and possiblystrong carbon uptake in the tropics.! The role of oceans as CO 2 sources andsinks is a major source of uncertainty.The role played by a warming ocean seems tobe unquestioned. The solubility of CO 2 in waterdecreases with increasing temperature – roughly by4 percent per degree C. Therefore, the ability of awarming ocean to absorb CO 2 diminishes – orconversely, a warming ocean will give up CO 2 to awarming atmosphere. Observationally, ice-core datashow that atmospheric CO 2 increases followed (didnot precede) the rapid warmings of pastdeglaciations [Fischer 1999] by many centuries –although the increased CO 2 may well operate in afeedback loop and contribute to further warming.The details of this process are rathercomplicated. The IPCC does not discuss it beyondmentioning that CO 2 is absorbed in the colder partsof the ocean and may be released from upwellingwater in the warmer parts. A proper treatmentrequires knowing the detailed temperaturedistribution of the ocean in latitude and longitude. Itmust take into account ocean circulation and howthis brings CO 2 -rich colder water to the surface. Italso involves knowing the degree of saturation ofocean masses as a function of time and the thicknessof the mixed layer, likely a function of surfacewinds and sea state.The rate of CO 2 uptake by the ocean depends onthe difference between the partial pressure of CO 2 inthe atmosphere and the pressure that would exist ifthe ocean and the atmosphere were at equilibrium.Le Quere [2007] reports that the rate of uptake bythe Southern Ocean, one of the most importantCO 2 -absorbing regions, has slowed relative to whatwould be expected based solely on how fast theconcentration of atmospheric CO 2 has risen since1981. They attribute this shortfall to an increase inwindiness over the Southern Ocean, conveniently22
lamed on global warming. The authors predict thisrelative trend will continue.Conclusion: While, evidently, there are still manyunknowns about CO 2 lifetimes, sources, and sinks,the overwhelming uncertainty is not in the sciencebut in the emission scenarios that depend on manysocio-economic assumptions.8. The Effects of Human Carbon DioxideEmissions Are BenignAnswers to questions regarding where CO 2 comesfrom and where it goes are of obvious importance inpredicting more accurately the effectiveness ofcontrols on human CO 2 emissions. But they are notnearly as important as knowledge of futureconsumption of fossil fuels or the likely effects ofhigher CO 2 concentrations on the planet’s plants andwildlife.Regarding the former, there is reason to believethe IPCC has exaggerated future emission trends,invalidating the temperature projections that rest onthe accuracy of those emission scenarios. Regardingthe latter, there is clear and compelling evidencethat higher levels of CO 2 , even if accompanied byhigher temperatures and changes in precipitation,would, on balance, be more beneficial than harmful.! The IPCC’s estimates of futureanthropogenic CO 2 emissions are too high.The IPCC used essentially the samemethodology for producing emission scenarios in itsAR4 as it did for TAR, a methodology that wasvigorously critiqued by Ian Castles and DavidHenderson in 2003 for containing basic errors ineconomics and the handling of economic statistics,excluding from consideration relevant publishedsources, and excluding economists from its writingand peer review processes [Castles and Henderson2003; Henderson 2005].For AR4 [2007], the IPCC ran computersimulations for one scenario that appeared in TAR(A2) and two new scenarios (B1 and A1B) [IPCC-AR4 p. 761]. The IPCC frankly admits in the bodyof AR4, though not in the SPM, that there isconsiderable uncertainty about the reliability of allof these scenarios and their possible effects onclimate:Uncertainty in predictions of anthropogenicclimate change arises at all stages of themodelling process described in Section 10.1.The specification of future emissions ofgreenhouse gases, aerosols and their precursorsis uncertain (e.g. Nakicenovic and Swart, 2000).It is then necessary to convert these emissionsinto concentrations of radiatively active species,calculate the associated forcing and predict theresponse of climate system variables such assurface temperature and precipitation (Figure10.1). At each step, uncertainty in the true signalof climate change is introduced by errors in therepresentation of Earth system processes inmodels (e.g., Palmer et al. 2005) and by internalclimate variability (e.g., Selten et al., 2004). ...Such limitations imply that distribution of futureclimate responses from ensemble simulationsare themselves subject to uncertainty... [p. 797]The IPCC grossly exaggerates the long-term(though not the short-term) increase in emissionsfrom poor countries. It does so by converting GrossDomestic Product estimates for wealthy and poorcountries into a common currency (U.S. dollars)using market exchange rates instead of purchasingpower parity. This method overstates the baselineincome disparity. Because the IPCC projects thatpoor nations will catch up to or even surpasswealthy nations in per-capita income by the end ofthe century, the inflated disparity in startingpositions means much greater economic activitymust take place, and more greenhouse gas emissionswould be released into the atmosphere.The assumption that poor countries would growas fast as the IPCC predicts is entirely implausibleand would be unprecedented in the history of theworld. For example, the IPCC predicts all of Asiawould increase real incomes by a factor of 70 to 1,whereas incomes even in fast-growing Japanincreased by ‘only’ a factor of 20 to 1 in thetwentieth century. According to even the mostconservative story lines used by the IPCC,per-capita GDP in the U.S. in 2100 would besurpassed by Estonia, Latvia, Lithuania, NorthKorea, Malaysia, Singapore, Hong Kong, Libya,Algeria, Tunisia, and Argentina [Castles andHenderson 2003].23
Page 1 and 2: Nature, Not Human Activity,Rules th
Page 3 and 4: ForewordIn his speech at the United
Page 5 and 6: group of activists wrote the all-im
Page 7: that action must be taken to reduce
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Page 15 and 16: Global and U.S. Mean Surface Temper
Page 19 and 20: verification of the IPCC’s analys
Page 21 and 22: ! Global warming prior to 1940 was
Page 23 and 24: Lockwood and Fröhlich [2007] have
Page 25 and 26: Figure 16: A result from the U.S. N
Page 27 and 28: Sea Level Since Last Glacial Maximu
Page 29 and 30: It is likely that actual SL observa
Page 31: Figure 21: CO 2 levels versus latit
Page 35 and 36: ates were linearly related to avera
Page 37 and 38: Estimated Annual Impact on U.S. ofD
Page 39 and 40: About the ContributorsAnderson, War
Page 41 and 42: ReferencesAnonymous 1994. IPCC’s
Page 43 and 44: Keatinge W.R. et al, 2000. Heat rel
Page 45 and 46: Rahmstorf, S., et al. 2007. Recent
Page 47 and 48: AcronymsAGW Anthropogenic Global Wa
Page 49 and 50: Labohm, Hans, Simon Rozendaal, and

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