Jan 27, 2009

Twenty Years of Global Warming – Myths and Facts

      Human-caused Global Warming (GW) has been one of the most common headline-makers during the last twenty years. The updated concept of GW presumes that human industrial activities result in increasing carbon dioxide (CO2) and methane in the atmosphere, where they cause deleterious earth warming by the greenhouse effect, the major contributor being burning the fossil fuels, the minor one being farming. The population of developed countries has been frightened by expected floods, diseases,
hurricanes, and wars – the same plagues which were once believed to follow the appearance of a comet in the sky, and which still afflict the people of developing countries even without warming or other warnings. The organizations studying the popular catastrophe (IPCC, UNFCCC, etc.) employ thousands of social and other scientists, as well as artists, journalists and lawyers, who fight against the danger with the fervor of crusaders and Don Quixote combined, attacking unbelievers and supposed perpetrators. An unbeliever, whether a mathematician or other non-believing non-social scientist is usually de-legitimized as not being a GW expert[1]; a perpetrator is neutralized, for example flatulent cows releasing greenhouse methane are inoculated against flatulency[2], or a flatulency tax is imposed upon their owners[3]. In Mass. v. EPA, environmental groups, together with several states led by Massachusetts, challenged EPA and claimed that Massachusetts experiences harm from warming, for example from potentially rising sea levels; the US Supreme Court accepted the evidence and ruled, in April 2007, that greenhouse gases such as CO2 are air pollutants that can be regulated[4]. The anti-warming fighters are justly rewarded, some by a decent salary, others – IPCC and Al Gore – by a Nobel parize and glory. Although it was shown that the number of hurricanes has not changed[5], and that global warming would cause less diseases than an eventual global cooling, and although it is admitted that the catastrophic scenarios are hypothetic and that – even if real – GW could not be averted anyway by existing technologies, the most fundamental GW fighters have requested that we wear less shoes, take less showers, dilute our gasoline with alcohol, and convert our fields to biofuel factories. They have also tried to impose various national CO2 emission reductions during the Kyoto conference, for example 7% onto the United States and 0% onto Russia. It has turned out that a temperature-time graph, converted to the GW symbol on the fighters' flag (famous "hockey stick" shape[6]), was in fact adapted to look more alarming by the Nobel prize winning IPCC (Intergovernmental Panel on Climate Change). Further, it has turned out that the biofuel production destroys rain forests and whole biotopes, that it destroys soil by pesticides and erosion, and that it results, in fact, in an increased greenhouse gas production.
      The main argument of the GW fighters include the observed increase of the CO2 levels in the earth atmosphere during the last hundred years, allegedly accompanied by a global temperature increase; the second main argument is the experimentally found correlation between the CO2 levels and temperatures during the earth geological history, for example during the glacial and interglacial periods in the last one million years, as documented in the Antarctic ice samples. The GW skeptics note that an eventual warming is not global, giving many earth locations which have gotten cooler during the past one hundred years, and further they note that even the warmed locations stopped warming during the 1940-70 period, despite the apparently continuing CO2 increase. Sophisticated analytical methods have indeed revealed that the atmospheric concentrations of CO2 and methane, as well as the earth surface temperatures, have been oscillating during the last million years, all three parameters in the same rhythm, the prominent oscillation intervals being 20,000 and 100,000 years. Said correlation between CO2 and temperature during periodically changing ice ages is used by the GW fighters as an argument for the importance of CO2 in the atmosphere, implying that the increase in the CO2 concentration in the atmosphere may cause the temperature increase now as it caused the temperature increase during the interglacial periods[7]. However, the reason of the temperature oscillations during the earth history lies outside the human reach, and it even seems to have not much in common with CO2. The astrologists would be nearer to the truth here than the GW fighters – the observed temperature oscillations seem to be caused by planets.
      In the 1920s, Milutin Milankovitch, a Serbian astronomer studying the gravitational effects of the planets on the earth illumination, predicted that the tilt of the earth axis, its precession, and the changes in the earth orbit eccentricity should cause climate oscillations with periods of about 40,000 years, 20,000, and 100,000 respectively[8]; his predictions were confirmed several years after his death. The planets, mainly Venus, Jupiter and Saturn, cause ice ages. So, if CO2 and temperature oscillate in phase, and the CO2 variation is not the cause of the temperature variation, the logical conclusion is that the CO2 change is the effect and the temperature is the cause, or alternatively, that both CO2 and temperature are effects of an unknown third cause; the former seems to be the case.
      The earth ocean represents a huge reservoir of dissolved CO2. With increasing temperatures, CO2 is pushed from the ocean out to the atmosphere, as gas solubility decreases with increasing temperature, and at lower temperatures, CO2 again dissolves – something that we normally observe in a glass of soda or water. This could explain why the CO2 concentrations followed the temperature changes caused by the planets. The temperature-solubility dependence could explain also the historical changes in methane concentrations. Furthermore, it has now been surprisingly found that the plants form methane, the amount explaining up to 40% methane emissions formerly ascribed to human activities[9], wherein more methane is formed at warmer periods. The human-caused temperature forcing (energy heating the atmosphere), as estimated by GW proponents, represents about 0.3% of the incoming energy from the sun[10]. The astronomical effects are much greater than the human forcing. It should be noted that beside said Milankovitch effects, the sun itself occasionally changes its total radiation energy, affecting the earth climate, the most famous of such changes being the 11-years sunspot cycle. So much advertised CO2, ranging from 250 to 350 ppm during the recent history, is now near to its lowest concentration over the last 300 million years during which it was between 500 and 3000 ppm[11]. Even after burning all fossil fuels (assessed to contain about 10,000 billion tons of carbon), the released CO2 would amount to less than CO2 dissolved in the oceans (assessed to contain 38,000 billion tons of carbon[12]). Moreover, the plants consume CO2 in the process of photosynthesis and their growth is supported by increasing CO2; the photosynthetic organisms and the oceans are a huge buffer prepared to absorb much CO2. The greenhouse effect of CO2 seems to have been overestimated; the combined astronomical and meteorological effects are much greater than said human temperature forcing. Due to the greenhouse effect, the earth atmosphere supposedly keeps the surface temperature higher by several tens degrees; the GW proponents ascribe a great part of said greenhouse effect to CO2. The planet Venus has much more CO2 than the earth, containing 96.5% CO2 in its atmosphere, compared to less than 0.04% CO2 in the earth atmosphere; since Venus has nearly 100times more massive atmosphere than Earth[13]; the greenhouse effect should be 250,000times stronger on Venus than on Earth – but it is not. The contribution of CO2 to the whole effect is less than originally supposed, and CO2 probably does not substantially contribute to the historical warming periods. If CO2 had been the cause of the known periods of warming and not the effect, the system would not be stable, because CO2 released from the ocean by a slight temperature increase would amplify said increase (positive feedback) and lead to a still greater release – causing a chain-reaction-like, explosive release of all dissolved CO2 from the ocean, but the ocean does not seem to be about to explode. Whatever is the real effect of CO2 on the earth climate, its contribution to the total greenhouse effect is now assessed at only 9-26%[14], water vapor supposedly contributing up to 70%, the clouds notwithstanding. New facts push the fundamental fighters to adjust their GW doctrine; the initially all-important CO2 must share its importance with methane, and raising cattle now allegedly contributes to an eventual greenhouse effect the same way as traffic, while deforestation apparently contributes still more. Totally contradicting the original GW doctrine is a new hypothesis which states that the GW was started by our ancestors via their farming practices 8,000 years ago[15]. The GW fighters are even prepared to explain eventual cooling as a result of the global warming, stating that GW may push the earth climate faster toward sudden shift[16], no matter in which direction; "global warming" becomes "climate change".
      What then remains from the initial allegations of the GW fighters? Not so much. CO2 and methane were not the cause but the effect of the temperature changes during the glacial and interglacial changes periods. It is also known that temperature oscillations always occurred, both in far and in near history. In some geological periods, the ocean level was by more than one hundred meters higher than today, and as for nearer history, it is known that warmer periods enabled the Vikings to settle in Greenland, and the British to grow vine. Of course, when risking a global catastrophe, even at a very low probability, all the facts should be taken seriously. Burning fossil fuels indeed contributes to a certain increase of CO2 in the atmosphere. If it should represent any problem, there is enough uranium to replace fossil fuels in all power plants for the next one thousand years. The thermonuclear fusion, already tested in the pilot scale, will provide all necessary energy later on. Unfortunately, the most fundamental GW fighters distrust the nuclear energy still more than they dislike fossil fuels.
      When evaluating the importance of GW, it can be concluded that, if it exists, it may protect us from the oncoming ice age[15] as Arrhenium suggested, and if GW does not exist, it contributed (beside providing exciting reading to masses and good salaries for some of the fighters) to developing new "clean" or "green" technologies. The patents and patent applications comprising the words "global warming" amount today to about 10,500, while in 1989 they counted merely 6 patent applications, and in 1988 zero. At the beginning, the new technologies related only to halogenated hydrocarbons, later they diversified to cover many other subjects. Thousands more patent documents deal with "clean technologies" inspired by the GW campaign, and many useful inventions may serve humankind even when global warming has been forgotten, and when new problems arise – possibly global cooling.

[1] Sci. Am. 286(1), 2002, 59-67
[2] http://en.wikipedia.org/wiki/mitigation_of_global_warming
[3] http://en.wikipedia.org/wiki/flatulence
[4] Sci.Am. 297(1), 2007, 10-11
[5] http://www.nhc.noaa.gov/pastdec.shtml; Sci.Am. 297(1), 2007, 27-33
[6] Sci. Am. 295(3), 2006, 17; http://en.wikipedia.org/wiki/hockey_stick_controversy
[7] Sci.Am. 260(4), 1989, 18-26; Sci.Am. 290(3), 2004, 40-49; Sci.Am. 296(2), 2007, 41-45
[8] Sci.Am. 278(2), 1998, 66-71
[9] Sci.Am. 296(2), 2007, 41-45
[10] Sci.Am. 290(3), 2004, 40-49
[11] Sci.Am. 295(4), 2006, 42-49
[12] www.eia.doe.gov/bookshelf/brochures/greenhouse/greenhouse.pdf
[13] http://www.nineplanets.org/
[14] http://en.wikipedia.org/wiki/greenhouse_gas
[15] Sci.Am. 292(3), 2005, 34-41
[16] Sci.Am. 291(5), 2004, 40-47