Op zaterdag 24 maart 2018 16:56 schreef MrRatio het volgende:[..]
Mmmm, ik ben het voor meer dan 99% eens met de bijdragen van de tevreden atheïst, maar hier maakte hij/zij een slip of de pen. Er is geen bewijs dat alle wetenschappers opwarming goed vonden. Ik kan me wel voorstellen dat er een meerderheid is die er zo over denkt, maar 100% van de wetenschappers-dat hoeft niet het geval te zijn. Ik kan me voorstellen dat een professor Iberische dichtkunst er geen mening over heeft.
Ik zag een stukje tekst over een gesuggereerde consensus in de 70er jaren dat wetenschappers global warming door CO
2 vreesden. Ik heb daar enkele voorbeelden tegenover gezet. Zo helder was het niet.
Het is geen alles of niets discussie.
"De suggestie dat de klimaatwetenschap Global Cooling voorspelde in de jaren '70 is dan ook onjuist. Het was meer een media onderwerp"
O ja?
Hansen van Nasa in 1981: "[T]he temperature in the Northern Hemisphere decreased by about 0.5°C between 1940 and 1970, a time of rapid CO2 buildup. ... Northern latitudes warmed ~ 0.8°C between the 1880's and 1940, then cooled - 0.5°C between 1940 and 1970."
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Dat was een van de argumenten, de temperatuur steeg tussen 1900 en 1940, en daalde daarna tussen 1940 en 1970- om tot 2000 weer te stijgen, en stabiel te blijven-of zelfs lichtjes dalen- vanaf 2000.
Het in 1970 extrapoleren van de temperatuurdaling tussen 1940 en 1970 naar de verre toekomst maakt een nieuwe ijstijd aannemelijk.
Het was meer een media-onderwerp. Als ik even zoek kom ik van alles tegen:
National Academy of Sciences, 1975 "Starr and Oort (1973) have reported that, during the period 1958-1963, the hemisphere's (mass-weighted) mean temperature decreased by about 0.6 °C. ... Since the 1940's, mean temperatures have declined and are now nearly halfway back to the 1880 levels. ... There seems little doubt that the present period of unusual warmth will eventually give way to a time of colder climate ... [T]here is a finite probability that a serious worldwide cooling could befall the earth within the next hundred years. ... [A]s each 100 years passes, we have perhaps a 5 percent greater chance of encountering its [the next glacial's] onset."
NOAA, 1974 "Many climatologists have associated this drought and other recent weather anomalies with a global cooling trend and changes in atmospheric circulation which, if prolonged, pose serious threats to major food-producing regions of the world. ... Annual average temperatures over the Northern Hemisphere increased rather dramatically from about 1890 through 1940, but have been falling ever since. The total change has averaged about one-half degree Centigrade, with the greatest cooling in higher latitudes."
"[T]he average growing season in England is already two weeks shorter than it was before 1950. Since the late 1950's, Iceland's hay crop yield has dropped about 25 percent, while pack ice in waters around Iceland and Greenland ports is becoming the hazard to navigation it was during the 17th and 18th centuries. ... Some climatologists think that if the current cooling trend continues, drought will occur more frequently in India--indeed, through much of Asia, the world's hungriest continent. ... Some climatologists think that the present cooling trend may be the start of a slide into another period of major glaciation, popularly called an 'ice age'."
Cimorelli and House, 1974 "[B]etween 1880 and 1940 a net warming of about 0.6°C occurred, and from 1940 to the present our globe experienced a net cooling of 0.3°C. ... [I]t has since been found that the rate of temperature increase decreases with increasing CO2 ... [A]n increase in man-made global particulates by a factor of 4.0 will initiate an ice-age. In order that we safeguard ourselves and future generations from a self-imposed ice-age it is necessary that we effectively monitor global concentrations of particulate matter."
8. National Academy of Sciences, 1975 "Starr and Oort (1973) have reported that, during the period 1958-1963, the hemisphere's (mass-weighted) mean temperature decreased by about 0.6 °C. ... Since the 1940's, mean temperatures have declined and are now nearly halfway back to the 1880 levels. ... There seems little doubt that the present period of unusual warmth will eventually give way to a time of colder climate ... [T]here is a finite probability that a serious worldwide cooling could befall the earth within the next hundred years. ... [A]s each 100 years passes, we have perhaps a 5 percent greater chance of encountering its [the next glacial's] onset."
Hare, 1971 "[M]ost recent years of hemispheric surface temperatures (Mitchell, 1970) show rises of about 0.6C over the 0-80N belt between 1880 and 1940, followed by a subsequent decline to current temperatures about 0.3C above 1880. ... It is clear, however, that sound meteorological estimates of the troposphere and surface warming to be expected from this increase [in CO2] (e.g., Manabe and Wetherland, 1967) do not account for the observed temperatures variations. The rise between 1880 and 1940 was much greater than the computed carbon dioxide effect, and since 1940 temperatures have actually fallen as the rise in [CO2] mixing ratio accelerated."
Gribbin, 1975 "A recent flurry of papers has provided further evidence for the belief that the Earth is cooling. There now seems to be little doubt that changes over the past few years are more than a minor statistical fluctuation. ... The observed cooling corresponds to a re-establishment of the 'Little Ice Age' which persisted for several hundred years up to the end of the nineteenth century"
Flohn, 1974 "Since about 1945 [to 1974], global cooling, on a scale of -0.01°C/yr [-0.3°C total], has reversed the warming trend of the first decades of our century. ... A large majority of the participants of the symposium concluded that the present warm epoch has reached its final phase [...]-the natural end of this interglacial epoch is 'undoubtedly near'."
Denton and Karlén, 1973 "Viewed as a whole, therefore, the Holocene experienced alternating intervals of glacier expansion and contraction that probably were superimposed on the broad climatic trends recognized in pollen profiles and deep-sea cores. Expansion intervals lasted up to 900 yr and contraction intervals up to 1750 yr. ... Should this pattern continue to repeat itself, the [ongoing, current] Little Ice Age will be succeeded within the next few centuries by a long interval of milder climates similar to those of the Roman Empire and Middle Ages. ... Holocene glacier and climatic fluctuations, because of their close correlation with short-term C14 variations, were caused by varying solar activity."
Brinkmann, 1979 "Concern about the impact of the recent downward trend in the average surface temperature for the 'Northern Hemisphere' (Reitan, 1974; Angell and Korshover, 1975) on the world food supply has led to an increasing interest in possible changes in the length of the growing season (NRC, 1976; NRC, 1977). ... Increased variability has been proposed to be linked to hemispheric cooling [...] would cause greater extremes in weather (Bryson, 1975; Lamb, 1975)."
Bryson and Wendland, 1975 "Since 1940, the effect of the rapid rise of atmospheric turbidity appears to have exceeded the effect of rising carbon dioxide, resulting in a rapid downward trend of temperature. There is no indication that these trends will be reversed, and there is some reason to believe that man-made pollution will have an increased effect in the future."
Collis, 1975 "It is not clear how such favorable and relatively consistent conditions are related to the higher temperatures in this century or the peaking of temperatures around 1940. The reversal of this warming trend, however, could mark the beginning of a new ice age"
Schneider, 1974 "In the last century it is possible to document an increase of about 0.6°C in the mean global temperature between 1880 and 1940 and a subsequent fall of temperature by about 0.3°C since 1940. In the polar regions north of 70° latitude the decrease in temperature in the past decade alone has been about 1°C, several times larger than the global average decrease. Up till now, past climatic changes (except possibly those of the last few decades [of cooling temperatures]) could hardly have been caused by man's activities. ... Some scientists already feel that particles might be responsible for the recently observed decrease in the earth's temperature"
Gates, 1976 "Recorded data show that from 1940 to the early 1970s the average temperature in the Northern Hemisphere slowly decreased, with a net cooling of approximately 1°F [-0.55 °C] over the continents and less cooling over the oceans. We also know that during the period from about 1890 to 1940 the air over at least the continents of the Northern Hemisphere underwent a gradual warming of over 1.5°F [+0.83°C]. ... Whether such fluctuations are primarily the result of man's activities or are only natural climatic variations remains an open question."
En zo kan ik nog tientallen andere wetenschappelijke bronnen. Dus de opmerking van Cynicus, het was maar een media-dingetje is hierbij hopelijk begrepen weerlegd te zijn. Zo niet, dan kan ik hier nog tientallen voorbeelden extra hier plaatsen.