Nature, Not Human Activity, Rules the Climate - Science ...

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Figure 24: Phanerozoic CO 2 : CO 2 concentrations for the past 600 million years, in parts per million (left)and as multiples (up to a factor ~20) of current concentration (right). The past 400,000-year period issqueezed into a thin sliver on the left. Dots represent data, and lines represent various models [Hayden2007]. Note the significant downard trend in CO 2 levels in the past 200 million years.! Higher concentrations of CO 2 would bebeneficial to plant and animal life.An extensive scholarly literature documents thefact that increases in CO 2 give rise to many changesthat are beneficial. In the geologic past, CO 2 levelshave been many times higher than present values(Figure 24) and have sustained a large flora andfauna [Berner 1997;Berner and Kothaualla 2001;IPCC-AR4 2007, p. 441].Plants use CO 2 to produce the organic matterout of which they construct their tissues. Higherlevels of CO 2 in the air enable plants to grow bigger,produce more branches and leaves, expand theirroot systems, and produce more flowers and fruit[Idso 1989]. Laboratory experiments show that a300 ppm increase in the CO 2 content typically raisesthe productivity of most herbaceous plants by aboutone-third [Kimball 1983; Idso 1992]. Some 176experiments on trees and other woody plants reveala mean growth enhancement of 48 percent for a 300ppm increase in atmospheric CO 2 content [Poorter1993; Ceulemans and Mousseau 1994; Wullschlegeret al. 1995, 1997].Higher levels of CO 2 cause plants to producefewer leaf stomatal pores per unit area of leafsurface, and to open those pores less widely[Woodward 1987; Morison 1987]. Both of thesechanges tend to reduce most plants’ rates of waterloss by transpiration, making them better able towithstand drought conditions [Tuba et al. 1998],enabling terrestrial vegetation to begin to win backlands previously lost to desertification [Idso andQuinn 1983].Atmospheric CO 2 enrichment, finally, helpsplants cope with the negative effects of a number ofother environmental stresses, including high soilsalinity, high air temperature, low light intensity,low levels of soil fertility [Idso and Idso 1994], lowtemperature stress [Boese et al. 1997], oxidativestress [Badiani et al. 1997], and the stress ofherbivory (insect and animal grazing) [Gleadow etal. 1998].Concerns have been raised that coral reefs couldbe harmed by rising CO 2 emissions through aCO 2 -induced acidification of the world’s oceans.But a study of calcification rates of Porites coralcolonies on Australia’s Great Barrier Reef (GBR)found “the 20th century has witnessed the secondhighest period of above-average calcification in thepast 237 years” [Lough and Barnes 1997]. Researchby the same authors has found GBR calcification24
ates were linearly related to average annual seasurface temperature, such that “a 1ºC rise in averageannual SST increased average annual calcificationby 0.39 g cm -2 y -1 .”Warmer ocean temperatures are likely toincrease coral reef calcification “due to anenhancement in coral metabolism and/or increasesin photosynthetic rates of their symbiotic algae”[McNeil et al. 2004]. This biologically drivenprocess may account for the ability of coral tosurvive major changes in temperature over thecourse of millions of years.The evident survival of polar bears and otherspecies, of polar ice sheets and glaciers, and ofcorals, all demonstrate that warmer temperatureshave not been catastrophic, as many seem to fear. Incontrast, a markedly colder climate would certainlybe harmful. Were a warmer climate also to beharmful, then logic would seem to dictate that thepresent climate is optimal – an unlikely occurrence.! Higher concentrations of CO 2 are notresponsible for weather extremes, storms,or hurricanes.According to the IPCC, “It is very likely thathot extremes, heat waves, and heavy precipitationevents will continue to become more frequent”[IPCC-AR4 2007, SPM, p.12]. This argument isexpanded on in the main report. The phrase“continue to become more frequent” implies thatthese events have already become more frequent.But have they?Hall [2007] has reviewed climate data for the 50U.S. states; his chart of the number of record-hightemperatures by year goes back to 1884 (Figure 25).The chart shows 25 extreme high temperaturerecords set in 1934 and 29 in 1936, but none in2001, 2003, 2004, or 2005. There is no evidencefrom U.S. records that extreme high temperaturesare on the increase.Heat waves in Europe can almost entirely beexplained by more frequent occurrence ofFigure 25: Extreme high-temperature values recorded, by state, in the United States since 1880 [Hart2007]. Note the peaking around 1940 but not during recent decades; it suggests that the 1930s – notthe 1990s – were the warmest decade of the twentieth century.25
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
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Page 33: lamed on global warming. The author
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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