Beste Cees,
Jij haalt als bewijsvoering namelijk o.a. Svante Arrhenius aan die:
- 1. Meer dan 50% afzat met zijn uitkomsten van de invloed van CO2 op de wereldwijde temperaturen vergeleken bij de huidige inzichten.
- 2. En veel belangrijker hier. Geen enkel verband legde met de invloed die de mens zou kunnen hebben op het verdubbelen van de hoeveelheid CO2 in de atmosfeer.
Wat Arrhenius interesseerde waren de verschillende ijstijden en een verklaring vinden voor het voorkomen van deze. Pas veel later zijn de uitkomsten van zijn experimenten betrokken op de (Let wel) AGW-CO2 Hypotheses.
Vriendelijke groet,
Jacob
Beste Jacob,
Je wrijft mij een harde toon aan. Daar kom ik later nog op terug. Misschien zit daar iets in en is dat van belang.
Waar het hier om ging zijn de feiten. Het zijn feiten die van belang zijn voor een goed beeld van wat er aan de hand is. En daarom van belang in de discussie. Wie de feiten niet kent of manipuleert (de populisten) heeft cq schept een probleem.
Ik wil dan ook graag op jouw kritiek ingaan, waar je suggereert dat de feiten die ik noem niet kloppen.
Je noemt Arrhenius en beweert dat het begrip AGW-hypothese hier niet van toepassing is. Je zegt bovendien dat dit gegeven belangrijker is dan het feit dat Arrhenius er behoorlijk naast zat. Dat laatste is overigens met zijn gebrekkige model niet verwonderlijk. De hypothese was aanwezig; en hij publiceerde erover. Ik lees dat hij in 1908 zijn prognose, vanwege hogere CO2-uitstoot door verbranding van steenkool, al had bijgesteld.
Dat zijn eerste belangstelling de ijstijden waren weet ik natuurlijk ook; het is te lezen in onderstaande site (link) en daaruit gedestilleerd staat dat ook in mijn eerste posting.
In onderstaande link lees ik:
The next major scientist to consider the question was another man with broad interests, Svante Arrhenius in Stockholm. He too was attracted by the great riddle of the prehistoric ice ages. In 1896 Arrhenius completed a laborious numerical computation which suggested that cutting the amount of CO2 in the atmosphere by half could lower the temperature in Europe some 4-5°C (roughly 7-9°F) — that is, to an ice age level. But this idea could only answer the riddle of the ice ages if such large changes in atmospheric composition really were possible. For that question Arrhenius turned to a colleague, Arvid Högbom. It happened that Högbom had compiled estimates for how carbon dioxide cycles through natural geochemical processes, including emission from volcanoes, uptake by the oceans, and so forth. Along the way he had come up with a strange, almost incredible new idea.
It had occurred to Högbom to calculate the amounts of CO2 emitted by factories and other industrial sources. Surprisingly, he found that human activities were adding CO2 to the atmosphere at a rate roughly comparable to the natural geochemical processes that emitted or absorbed the gas. As another scientist would put it a decade later, we were "evaporating" our coal mines into the air. The added gas was not much compared with the volume of CO2 already in the atmosphere — the CO2 released from the burning of coal in the year 1896 would raise the level by scarcely a thousandth part. But the additions might matter if they continued long enough.(2) (By recent calculations, the total amount of carbon laid up in coal and other fossil deposits that humanity can readily get at and burn is some ten times greater than the total amount in the atmosphere.) So the next CO2 change might not be a cooling decrease, but an increase. Arrhenius made a calculation for doubling the CO2 in the atmosphere, and estimated it would raise the Earth's temperature some 5-6°C.(3)
Arrhenius did not see that as a problem. He figured that if industry continued to burn fuel at the current (1896) rate, it would take perhaps three thousand years for the CO2 level to rise so high. Högbom doubted it would ever rise that much. One thing holding back the rise was the oceans. According to a simple calculation, sea water would absorb 5/6ths of any additional gas. (That is roughly true over a long run of many thousand years, but Högbom and Arrhenius did not realize that if the gas were emitted more rapidly than they expected, the ocean absorption could lag behind.) Anyway temperatures a few degrees higher hardly sounded like a bad idea in chilly Sweden. Another highly respected scientist, Walter Nernst, even fantasized about setting fire to useless coal seams in order to release enough CO2 to deliberately warm the Earth's climate.(4*)
Arrhenius brought up the possibility of future warming in an impressive scientific article and a widely read book. By the time the book was published, 1908, the rate of coal burning was already much higher than in 1896, and Arrhenius suggested warming might appear wihin a few centuries rather than millenia. Yet here as in his first article, the possibility of warming in some distant future was far from his main point. He mentioned it only in passing, during a detailed discussion of what really interested scientists of his time — the cause of the ice ages. Arrhenius had not quite discovered global warming, but only a curious theoretical concept.(5)
2. Högbom (1894) ; the essentials are quoted by Arrhenius (1896), pp. 269-73; see also Berner (1995); for further background, see Arrhenius (1997). The word "evaporating" was first used by Lotka in 1908, see Pilson (2006). BACK
3. He also did computations for 1.5-, 2.5- and 3-fold increases. Arrhenius (1896), 266; see Crawford (1996), chap. 10; Crawford (1997); reprinted with further articles in Rodhe and Charlson (1998). BACK
4. Nernst also noted that the additional CO2 would fertilize crops. James Franck, interview by Thomas Kuhn, p. 6, Archive for History of Quantum Physics, copies at AIP and other repositories. BACK
5. Arrhenius (1896); revised calculations, finding a somewhat lower effect, were given in Arrhenius (1901) ; popularization: Arrhenius (1908), chap. 2. BACK
Groet,
Cees
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