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Remember Global Cooling ? Libs trying to cover their lying ass--UPDATE
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| Remember Global Cooling ? Libs trying to cover their lying ass--UPDATE
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| redeye |
Why scientists find climate change so hard to predict.
WEB EXCLUSIVE
By Jerry Adler
Updated: 4:41 p.m. CT Oct 23, 2006
Oct. 23, 2006 - In April, 1975, in an issue mostly taken up with stories about the collapse of the American-backed government of South Vietnam, NEWSWEEK published a small back-page article about a very different kind of disaster. Citing "ominous signs that the earth's weather patterns have begun to change dramatically," the magazine warned of an impending "drastic decline in food production." Political disruptions stemming from food shortages could affect "just about every nation on earth." Scientists urged governments to consider emergency action to head off the terrible threat of . . . well, if you had been following the climate-change debates at the time, you'd have known that the threat was: global cooling.
More than 30 years later, that little story is still being quoted regularly—as recently as last month on the floor of the Senate by Republican Sen. James Inhofe, chair of the Environment and Public Works Committee and the self-proclaimed scourge of climate alarmists. The article's appeal to Inhofe, of course, is not its prescience, but the fact that it was so spectacularly wrong about the near-term future. Even by the time it appeared, a decades-long trend toward slightly cooler temperatures in the Northern hemisphere had already begun to reverse itself—although that wouldn't be apparent in the data for a few years yet—leading to today's widespread consensus among scientists that the real threat is actually human-caused global warming. In fact, as Inhofe pointed out, for more than 100 years journalists have quoted scientists predicting the destruction of civilization by, in alternation, either runaway heat or a new Ice Age. The implication he draws is that if you're not worried about being trampled by a stampede of woolly mammoths through downtown Chicago, you don't have to believe what the media is saying about global warming, either.
But is that the right lesson to draw? How did NEWSWEEK—or for that matter, Time magazine, which also ran a story on the subject in the mid-1970s—get things so wrong? In fact, the story wasn't "wrong" in the journalistic sense of "inaccurate." Some scientists indeed thought the Earth might be cooling in the 1970s, and some laymen—even one as sophisticated and well-educated as Isaac Asimov—saw potentially dire implications for climate and food production. After all, Ice Ages were common in Earth's history; if anything, the warm "interglacial" period in which human civilization evolved, and still exists, is the exception. The cause of these periodic climatic shifts is still being studied and debated, but many scientists believe they are influenced by small changes in the Earth's orbit around the Sun (including its "eccentricity," or the extent to which it deviates from a perfect circle) and the tilt of its rotation. As calculated by the mathematician Milutin Milankovitch in the 1920s, these factors vary on interlocking cycles of around 20,000, 40,000 and 100,000 years, and if nothing else changed they would be certain to bring on a new Ice Age at some time. In the 1970s, there were scientists who thought this shift might be imminent; more recent data, according to William Connolley, a climate scientist at the British Antarctic Survey who has made a hobby of studying Ice Age predictions, suggest that it might be much farther off.
But in any case, climatologists now are mostly agreed that human impacts will swamp the effects of the Milankovitch cycles. The question has been, which specific impacts? In the mid-1970s, scientists were focusing on an increase of dust and "aerosols" (suspended droplets of liquid, mostly sulfuric acid) in the atmosphere. These, the result of increased agriculture and burning of coal in power plants, lower the Earth's temperature by reflecting sunlight back into space. Ironically, clean-air laws in North America and Europe had the effect of reducing aerosols (which cause acid rain), so the predominant influence on climate now is the buildup of carbon dioxide—which traps the Earth's heat in the lower atmosphere and contributes to global warming.
As late as 1992, in a story that for some reason has gotten far less attention, NEWSWEEK revisited the Ice Age threat, this time posing it as a perverse consequence of the greenhouse effect. Citing the theories of an "amateur scientist and professional prophet of doom named John Hamaker," the article raised the specter that a small increase in air temperature could cause more snow to fall in places like northern Greenland, where the ground is often bare. (Extremely cold air doesn't hold enough moisture for a good snowfall.) Increased snow cover, by reflecting more sunlight back into space, could trigger a return of the glaciers to North America. Although the intricate web of positive and negative feedbacks that control climate are still not fully understood, that particular scenario hasn't gotten much attention in the last decade.
The point to remember, says Connolley, is that predictions of global cooling never approached the kind of widespread scientific consensus that supports the greenhouse effect today. And for good reason: the tools scientists have at their disposal now—vastly more data, incomparably faster computers and infinitely more sophisticated mathematical models—render any forecasts from 1975 as inoperative as the predictions being made around the same time about the inevitable triumph of communism. Astronomers have been warning for decades that life on Earth could be wiped out by a collision with a giant meteorite; it hasn't happened yet, but that doesn't mean that journalists have been dupes or alarmists for reporting this news. Citizens can judge for themselves what constitutes a prudent response-which, indeed, is what occurred 30 years ago. All in all, it's probably just as well that society elected not to follow one of the possible solutions mentioned in the NEWSWEEK article: to pour soot over the Arctic ice cap, to help it melt. |
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| FatesWebb |
thanks for proving that humans have an impact on the climate
"But in any case, climatologists now are mostly agreed that human impacts will swamp the effects of the Milankovitch cycles"
I didnt think you supported that theory, but clearly you have posted evidence of it. |
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| Monster_Zero |
| He doesn't read the bullshit he posts... :) |
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| tamboozie |
| Yeah redeye and according to the tobaco institute cigarettes don`t cause cancer. |
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| NCMike06 |
Anyone want to start a pool on when the next 'oops we were wrong about global warming, its really global cooling now' nonsense starts from Newsweek and the MSM??
I'll say August 2016, just intime to try and influence a presidential election. Maybe Ozone Al will be running again... :burst: |
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| Ironpirate |
| this god damn global warming is making record lows in the south, lol |
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| tourette_ticker |
Quote: Originally posted by NCMike06
Anyone want to start a pool on when the next 'oops we were wrong about global warming, its really global cooling now' nonsense starts from Newsweek and the MSM??
I'll say August 2016, just intime to try and influence a presidential election. Maybe Ozone Al will be running again... :burst: |
Maybe sooner than you think.
Global Warming Takes a Break
By Sara Goudarzi
LiveScience Staff Writer
posted: 21 September 2006
04:14 pm ET
Despite the long term warming trend seen around the globe, the oceans have cooled in the last three years, scientists announced today.
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| Ass Boil |
14 Jan 2005
The global cooling myth
Filed under:
Climate Science
Paleoclimate
Greenhouse gases
Instrumental Record
FAQ
— william @ 5:31 am - ()
Every now and again, the myth that "we shouldn't believe global warming predictions now, because in the 1970's they were predicting an ice age and/or cooling" surfaces. Recently, George Will mentioned it in his column (see Will-full ignorance) and the egregious Crichton manages to say "in the 1970's all the climate scientists believed an ice age was coming" (see Michael Crichton’s State of Confusion ). You can find it in various other places too [here, mildly here, etc]. But its not an argument used by respectable and knowledgeable skeptics, because it crumbles under analysis. That doesn't stop it repeatedly cropping up in newsgroups though.
I should clarify that I'm talking about predictions in the scientific press. There were some regrettable things published in the popular press (e.g. Newsweek; though National Geographic did better). But we're only responsible for the scientific press. If you want to look at an analysis of various papers that mention the subject, then try http://www.wmconnolley.org.uk/sci/iceage/.
Where does the myth come from? Naturally enough, there is a kernel of truth behind it all. Firstly, there was a trend of cooling from the 40's to the 70's (although that needs to be qualified, as hemispheric or global temperature datasets were only just beginning to be assembled then). But people were well aware that extrapolating such a short trend was a mistake (Mason, 1976) . Secondly, it was becoming clear that ice ages followed a regular pattern and that interglacials (such as we are now in) were much shorter that the full glacial periods in between. Somehow this seems to have morphed (perhaps more in the popular mind than elsewhere) into the idea that the next ice age was predicatable and imminent. Thirdly, there were concerns about the relative magnitudes of aerosol forcing (cooling) and CO2 forcing (warming), although this latter strand seems to have been short lived.
The state of the science at the time (say, the mid 1970's), based on reading the papers is, in summary: "...we do not have a good quantitative understanding of our climate machine and what determines its course. Without the fundamental understanding, it does not seem possible to predict climate..." (which is taken directly from NAS, 1975). In a bit more detail, people were aware of various forcing mechanisms - the ice age cycle; CO2 warming; aerosol cooling - but didn't know which would be dominant in the near future. By the end of the 1970's, though, it had become clear that CO2 warming would probably be dominant; that conclusion has subsequently strengthened.
George Will asserts that Science magazine (Dec. 10, 1976) warned about "extensive Northern Hemisphere glaciation.". The quote is from Hays et al. But the quote is taken grossly out of context. Here, in full, is the small section dealing with prediction:
Future climate. Having presented evidence that major changes in past climate were associated with variations in the geometry of the earth's orbit, we should be able to predict the trend of future climate. Such forecasts must be qualified in two ways. First, they apply only to the natural component of future climatic trends - and not to anthropogenic effects such as those due to the burning of fossil fuels. Second, they describe only the long-term trends, because they are linked to orbital variations with periods of 20,000 years and longer. Climatic oscillations at higher frequencies are not predicted.
One approach to forecasting the natural long-term climate trend is to estimate the time constants of response necessary to explain the observed phase relationships between orbital variation and climatic change, and then to use those time constants in the exponential-response model. When such a model is applied to Vernekar's (39) astronomical projections, the results indicate that the long-term trend over the next 20,000 years is towards extensive Northern Hemisphere glaciation and cooler climate (80).
The point about timescales is worth noticing: predicting an ice age (even in the absence of human forcing) is almost impossible within a timescale that you could call "imminent" (perhaps a century: comparable to the scales typically used in global warming projections) because ice ages are slow, when caused by orbital forcing type mechanisms.
Will also quotes "a full-blown 10,000-year ice age" (Science, March 1, 1975). The quote is accurate, but the source isn't. The piece isn't from "Science"; it's from "Science News". There is a major difference: Science is (jointly with Nature) the most prestigous journal for natural science; Science News is not a peer-reviewed journal at all, though it is still respectable. In this case, its process went a bit wrong: the desire for a good story overwhelmed its reading of the NAS report which was presumably too boring to present directly.
The Hays paper above is the most notable example of the "ice age" strand. Indeed, its a very important paper in the history of climate, linking observed cycles in ocean sediment cores to orbital forcing periodicities. Of the other strand, aerosol cooling, Rasool and Schneider, Science, July 1971, p 138, "Atmospheric Carbon Dioxide and Aerosols: Effects of Large Increases on Global Climate" is the best exemplar. This contains the quote that quadrupling aerosols could decrease the mean surface temperature (of Earth) by as much as 3.5 degrees K. If sustained over a period of several years, such a temperature decrease could be sufficient to trigger an ice age!. But even this paper qualifies its predictions (whether or not aerosols would so increase was unknown) and speculates that nuclear power may have largely replaced fossil fuels as a means of energy production (thereby, presumably, removing the aerosol problem). There are, incidentally, other scientific problems with the paper: notably that the model used was only suitable for small perturbations but the results are for rather large perturbations; and that the estimate of CO2 sensitivity was too low by a factor of about 3.
Probably the best summary of the time was the 1975 NAS/NRC report. This is a serious sober assessment of what was known at the time, and their conclusion was that they didn't know enough to make predictions. From the "Summary of principal conclusions and recommendations", we find that they said we should:
Establish National climatic research program
Establish Climatic data analysis program, and new facilities, and studies of impact of climate on man
Develope Climatic index monitoring program
Establish Climatic modelling and applications program, and exploration of possible future climates using coupled GCMs
Adoption and development of International climatic research program
Development of International Palaeoclimatic data network
Which is to say, they recommended more research, not action. Which was entirely appropriate to the state of the science at the time. In the last 30 years, of course, enormous progress has been made in the field of climate science.
Most of this post has been about the science of 30 years ago. From the point of view of todays science, and with extra data available:
The cooling trend from the 40's to the 70's now looks more like a slight interruption of an upward trend (e.g. here). It turns out that the northern hemisphere cooling was larger than the southern (consistent with the nowadays accepted interpreation that the cooling was largely caused by sulphate aerosols); at first, only NH records were available.
Sulphate aerosols have not increased as much as once feared (partly through efforts to combat acid rain); CO2 forcing is greater. Indeed IPCC projections of future temperature inceases went up from the 1995 SAR to the 2001 TAR because estimates of future sulphate aerosol levels were lowered (SPM).
Interpretations of future changes in the Earth's orbit have changed somewhat. It now seems likely (Loutre and Berger, Climatic Change, 46: (1-2) 61-90 2000) that the current interglacial, based purely on natural forcing, would last for an exceptionally long time: perhaps 50,000 years.
Finally, its clear that there were concerns, perhaps quite strong, in the minds of a number of scientists of the time. And yet, the papers of the time present a clear consensus that future climate change could not be predicted with the knowledge then available. Apparently, the peer review and editing process involved in scientific publication was sufficient to provide a sober view. This episode shows the scientific press in a very good light; and a clear contrast to the lack of any such process in the popular press, then and now.
http://www.realclimate.org/index.php?p=94 |
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| Crazytree |
I will say that I watched a documentary recently about Werner Herzog filiming Fitzcarralodo in the Amazon... the documentary was called "Burden of Dreams"... and it estimated that the Amazon forest would be completely razed by 2004.
So you can take that to mean either we were wrong on our predictions, or conservation efforts really worked.
Likely a combination of both. |
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