The Scientists Are Not Divided
Despite the common perception amongst the general public that the scientists are divided about climate this is far from the case. In fact, there is hardly an area of science where they are more united in opinion than they now are on this topic. In 2004 Naomi Oreskes surveyed abstracts of every scientific paper she could find written on the subject of anthropogenic climate between 1993 and 2003. Of 928 papers not a single one took the position that global warming is not man-made. In 2013 a review by Cook et al in Skeptical Science, a periodical devoted to picking holes in scientific theories in order to disprove them (an important part of the methodology of science) found over 97% of the papers written between 1991 and 2011 that they had surveyed agreed with the consensus position that humans are causing global warming. Almost without exception every official scientific body in the world agrees with the consensus position.
Here is a list of them.
(Scientific Organizations That Hold the Position That Climate Change Has Been Caused by Human Action)
5. Academia de Ciencias Medicas, Fisicas y Naturales de Guatemala
13. Academy of Science of Mozambique
31. American Association of Wildlife Veterinarians
63. Cameroon Academy of Sciences
73. Colombian Academy of Exact, Physical and Natural Sciences
97. Indonesian Academy of Sciences
102. InterAcademy Council
121. Madagascar National Academy of Arts, Letters, and Sciences
122. Mauritius Academy of Science and Technology
138. Natural England
152. Romanian Academy
157. Royal Irish Academy
182. Sudanese National Academy of Science
196. Zambia Academy of Sciences
In America NASA, often in the person of the redoubtable James Hansen who is often regarded as the world’s foremost authority on climate, is unequivocal in its support of the consensus position. But in fact this stance has been taken up, now without exception, by every scientific body in America. Even the Association of Petroleum Scientists, who were understandably reluctant to concur, did so in 2007.
Here is a list of statements by these bodies
Statement on climate change from 18 American scientific associations. ?“Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver.” (2009)??
American Association for the Advancement of Science. ?“The scientific evidence is clear: global climate change caused by human activities is occurring now, and it is a growing threat to society.” (2006)
American Chemical Society?. “Comprehensive scientific assessments of our current and potential future climates clearly indicate that climate change is real, largely attributable to emissions from human activities, and potentially a very serious problem.” (2004)??
American Geophysical Union?. “Human?induced climate change requires urgent action. Humanity is the major influence on the global climate change observed over the past 50 years. Rapid societal responses can significantly lessen negative outcomes.” (Adopted 2003, revised and reaffirmed 2007, 2012, 2013)
American Medical Association ?“Our AMA … supports the findings of the Intergovernmental Panel on Climate Change’s fourth assessment report and concurs with the scientific consensus that the Earth is undergoing adverse global climate change and that anthropogenic contributions are significant.” (2013)??
American Meteorological Society?. “It is clear from extensive scientific evidence that the dominant cause of the rapid change in climate of the past half century is human-induced increases in the amount of atmospheric greenhouse gases, including carbon dioxide (CO2), chlorofluorocarbons, methane, and nitrous oxide.” (2012)??
American Physical Society? “The evidence is incontrovertible: Global warming is occurring. If no mitigating actions are taken, significant disruptions in the Earth’s physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now.” (2007)
The Geological Society of America?. “The Geological Society of America (GSA) concurs with assessments by the National Academies of Science (2005), the National Research Council (2006), and the Intergovernmental Panel on Climate Change (IPCC, 2007) that global climate has warmed and that human activities (mainly greenhouse?gas emissions) account for most of the warming since the middle 1900s.” (2006; revised 2010)??
?International academies: Joint statement ?“Climate change is real. There will always be uncertainty in understanding a system as complex as the world’s climate. However there is now strong evidence that significant global warming is occurring. The evidence comes from direct measurements of rising surface air temperatures and subsurface ocean temperatures and from phenomena such as increases in average global sea levels, retreating glaciers, and changes to many physical and biological systems. It is likely that most of the warming in recent decades can be attributed to human activities (IPCC 2001).” (2005, 11 international science academies)??
U.S. National Academy of Sciences?. “The scientific understanding of climate change is now sufficiently clear to justify taking steps to reduce the amount of greenhouse gases in the atmosphere.” (2005)??
U.S. GOVERNMENT AGENCIES
?U.S. Global Change Research Program. ?“The global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases. Human ‘fingerprints’ also have been identified in many other aspects of the climate system, including changes in ocean heat content, precipitation, atmospheric moisture, and Arctic sea ice.” (2009, 13 U.S. government departments and agencies).
How is it, then, that, in the face of this overwhelming unanimity amongst the scientists, the sceptics have been so successful in persuading the public that there is a scientific division of opinion on the issue? Much of the confusion has arisen from the scientific process itself. Scientists are trained sceptics. They greatly value what they call falsifiability. Any theory must be capable of being falsified if contrary data is discovered, and must survive every attempt to falsify it before it can be declared robust. Their whole methodology, with its precise process of data gathering, hypothesis, experiment, proof and peer review, is designed to test any theory to destruction before it is accepted. One or two experiments are never enough. But as more and more confirmation of a thesis arises more and more scientists come to accept it. But even then there are always diehards. Thus Priestley’s experiments were crucial in enabling Lavoisier to discover oxygen, but Priestley remained an opponent of Lavoisier to the end of his life. Quantum physics would never have even begun without Einstein’s discoveries. But Einstein himself remained a bitter opponent of quantum physics’ most basic proposition, that position and momentum can never both be measured at the same time because of the inherent uncertainty of phenomena at the quantum level, until his dying breath.
But the progress of science fells even these giants. You would not find a single scientist today who thinks that Einstein was right, and without question Einstein himself would now be one of them. In the end, there is so much evidence that scientists accept a new thesis as true universally. Anthropogenic climate change has now achieved that status, even though it is peculiarly resistant to scientific method. Because it is in the future experiments cannot be performed on it. The best scientists can do is to run computer models of possible scenarios. But the subject is so complicated, and future developments so uncertain, no-one can ever be sure that even the most powerful computers can give reliable information. Even the IPCC (unlike Christopher Booker and many of the newspapers one can’t help thinking) claims to be only 95% sure about man-made climate change. It is this aspect that has made many scientists cautious and has allowed the sceptics to make such play about scientific uncertainty.
But there is, in practice, no uncertainty. So much data has now been gathered and so many experiments performed, even the most sceptical scientists, although not, significantly, commentators who are not themselves scientists, accept the universal consensus. Yet if experiments cannot be performed, and the future is so uncertain and computer models are so unreliable, how can the scientists even be 95% sure? It is because of confluence of evidence. If you ask a scientist working in a particular discipline, as they all do: ‘are you 100% certain that in the area of your specialism climate change is man-made?’ he would probably say no. But he would say with confidence that he is 80% sure, because there is no other known explanation for what is happening. When every single department of study in the subject becomes almost sure, the possibility that they are all wrong becomes negligible to vanishing.
Once the nature of scientific method is understood, the kind of objections the sceptics raise begin to read quite differently. Thus Professor Akasofu’s scepticism about Arctic sea ice has a quite different significance from the one Booker reads into it. To start with, Akasofu was criticizing scientists who relied solely on measuring contemporary weather and feeding the data into computer models. But he must have been aware that even then other scientists were examining ice cores to discover information about weather through many past ages. Very properly, though, he was doubting whether enough data had yet been gathered, at that stage, to make definite pronouncements, although plenty of other scientists, not mentioned by Booker of course, were already convinced. Akasofu was the Einstein of Arctic sea ice. But now there is so much evidence that sea ice is melting at an amazing rate and no other credible cause can be found other than man-made global warming, there are virtually no scientists, I am sure it is safe to say, who do not accept the consensus position on sea ice, and in all probability, because Akasofu was an excellent scientist, he is one of them. Because this is what really good scientists do. They doubt until the evidence is so convincing it is no longer possible to do so. That is certainly now the case with the evidence from the ice cores concerning Arctic sea ice.
It is significant that Booker so often refers to authorities who are not themselves scientists. He spends an inordinate amount of time rubbishing Al Gore’s film An Inconvenient Truth, which to a journalist, of course, would be a target of great interest. But Gore’s film is irrelevant to serious science, and almost undoubtedly annoyed many consensus scientists even more than it did Booker. Stephen McIntyre is a statistical analyst, Ross McIntrick an economist and John McLean an IT analyst. Looked at from the point of view of their own disciplines their criticisms are cogent enough, but they look very different when seen from within the perspectives of the science they are criticizing. Thus from a statistical point of view the hockey stick graph, if you assumed it was meant to give a graphic account of the last thousand years of the earth’s climate as to the non-scientist it so obviously appears to do, was undoubtedly flawed. But this was not what it was doing. It gave a theoretical picture of what the earth’s climate would have been like if you discounted the influence of sunspots. Sunspots are flares on the surface of the sun that occur in episodes that can sometimes last for earthly centuries and warm the earth above its normal temperature. Such an episode occurred during the Middle Ages and resulted in the Medieval warm period. Logically enough, during periods when there are no sunspots the earth cools, as it did during what climate scientists call the Maunder minimum during the seventeenth and eighteenth centuries.
The crucial point to grasp, which explains why the hockey stick graph was so important to the IPCC, is that during the past few decades no sunspot activity has been observed. The graph shows that we should be going through a period of stability if not cooling, which is why in the nineteen-seventies before the enormity of man-made climate change had become apparent, scientists were forecasting a mini ice age (idiots, now they’re emitting hot air about global warming but in the seventies they were forecasting a mini ice age. Can you see any ice out of the window? Well I can’t). Why then are we not in a mini ice age? Scientists started to look for an answer. The whole purpose of the hockey stick graph was, precisely, to programme an algorithm which would exclude anything but possibly relevant evidence that the change was man-made, because, among others at that point, this was already a serious explanatory contender. The hockey stick graph, so reviled by sceptics, has been totally misunderstood by them. It is absurd to think that the scientists didn’t know that there had been a Medieval warm period and a Maunder minimum, and it took McIntyre’s and McIntrick’s work to find out. No scientist thought that the hockey stick graph was an account of the earth’s actual climate. It was a thought experiment, an instrument of scientific research. The sunspots, so beloved of sceptics, are evidence for the very opposite of what the sceptics think.
The same confusion emerges with nearly every argument that the sceptics make. The picture looks very different from within the purviews of science to the way it appears to common sense and in newspapers. I can’t say I’ve read either of the papers on droughts that Booker refers to on page149 of his book, neither the one from the Hadley Centre showing that there were more droughts in the last decade of the twentieth century than in the previous forty years, nor the one published slightly later showing that droughts had been far more intensive in the early twentieth century than in its last forty years and still less in its last decade. But I’d bet a pound to a penny that what the second paper showed was that the severe droughts of the early twentieth century were consequences of pronounced el Nino episodes (I’ll give an account of el Nino in the next chapter), while the crucial point made in the first paper was that the droughts of the late twentieth century could not be explained by el Nino. Why then, if the droughts of the early twentieth century were el Nino phenomena but the droughts later in the century were not, were the later droughts occurring? The likelihood that the culprit was man-made climate change became more and more likely as more data was gathered, and now is beyond question. Booker doesn’t tell you any of this. To the ordinary lay person, data that there were more droughts in the early twentieth century than in the later is conclusive evidence that droughts cannot be caused by fossil fuel use, because, as everybody knows, there was an the immense increase in fossil fuel use as the century progressed. But the first question a climate scientist would ask is: when were the el Nino years?
This abyss between different understandings is nowhere more in evidence than in Christopher Booker’s remark ‘not 2,500 but 53’. To the ordinary person, and still more to an IT or statistical analyst, news that only a tiny number of scientists, and those a self-regarding in-group, actually wrote the crucial Chapter 9 of the 2007 IPCC report, immediately suggests that this was only a small fraction and not statistically representative. ‘The relationship between the authors of Chapter 9 demonstrates a disturbingly tight network of scientists with common research interests and opinions’ wrote McLean. But this is how science works. Breakthroughs are always made by small tight-knit teams working on the frontiers of research, for the very reason that because they are on the frontiers most scientists in their discipline are not yet familiar with their work. This is why peer review is so immensely important in science. Newly published theories have to survive the critical assessment of peers. Booker has entirely missed the significance of the fact that the other 2,447 scientists were not withholding themselves from the case put forward by the authors of Chapter 9. In terms of scientific practice this was a massive endorsement. The 2447 were positive and active participants in the chapter because they were approving peer reviewers. The enquiry into the so-called e mail scandal at the University of East Anglia did indeed upbraid the climate scientists there for not sharing their data. But, far more importantly, it found nothing wrong with their science. Withholding data is a common, even if regrettable, practice in science and so not seen as reprehensible. Research cannot be conducted under a glare of publicity and science is not geared to investigation under freedom of information acts. But this was not the impression given. Scandal and chicanery are far more newsworthy than patient and excellent and accurate research. In the news, withholding the data was often conflated with deceiving both other researchers and the public.
There may have been a flood in East Anglia in 1953. But science tells us that until recently such extreme climate events did occur but they were rare. Now they are happening all over the world all the time. There is a constant tale of floods, droughts, hurricanes, tempests, earthquakes (some scientist think the greatly increased rate of earthquakes in the early twenty-first century may be to do with climate change too, because of the increased pressure of the sea on vulnerable parts of the earth’s crust, as it becomes more heavily charged with carbon), and tsunamis. Of course, the floods on the Somerset levels were to some extent caused by inadequate draining of the rivers, but not to see that this fits in with a global pattern you would have to be blind. The report in The Mail on Sunday about 533,000 more square metres of Arctic sea ice in 2013 than in 2012 was factually completely correct. But what the report was not telling you was that this was part of a fluctuating pattern of retreating sea ice. In some years it disappears at a faster rate than in others, so it can easily happen that in terms of the previous year there has been an increase in the amount of ice. But the evidence of an overall decline in the last thirty years, despite some years bucking the trend, is overwhelming. The unspoken implication of the report, that this is evidence that sea ice is not disappearing after all, was completely misleading.
Above all, though, the public, and most of the newspapers, have misunderstood the significance of the lack of evidence for an increase in global temperature since 1998, even though carbon emissions have steeply increased. The evidence is drawn from air temperature and to the ordinary person, who opens his front door in the morning and sniffs the air to see how cold it is, that clearly means that there has been no increase in temperature. But to a scientist air and sea temperature are inextricably linked. You can’t talk about one without the other. 1998 was a severe el Nino year, so measurement beginning with that year is starting with an exceptionally high base line. Yet every other indicator of climate change – more floods, droughts, melting of glaciers, rising sea levels and above all rising sea temperatures – are in line with predictions. Sceptics misunderstand phenomena because they see them as isolated. But the essence of climate science is the inter-action of causes. Air is absorbed by the sea which in turns affects the air. Air temperature may not have increased but its stability in the face of decreased sunspot activity, together with a consequent increase in sea temperature, is, paradoxically perhaps, prime evidence that global warming is happening.
To start with, air temperature, if related to sunspots or rather to their lack, should not be steady but far lower. Why isn’t it? Then, even more pertinently, we are going through a period of exceptionally strong trade winds, although of course, you don’t read about that in sceptical articles in newspapers. The winds blow the warm air across the Pacific. The stronger the winds the less warm air there is hanging around waiting to be measured. When it meets the cold air coming up from the Antarctic it is driven into the sea near Australia in what is known as the Pacific warm pool. There has been, consequently, a sharp rise in sea temperatures. The warmer air is being absorbed by the sea which, in turn, it is making warmer. When you take air temperatures and sea temperatures together in relation to each other, as any scientist would do, the evidence is overwhelming that average global temperature has not remained constant but has risen sharply since 1998. Since it is sea temperature that is the great driver of climate change, this is very alarming news indeed.
 Oreskes Naomi (Dec 2004): Beyond the Ivory Tower: the Scientific Consensus on Climate Change. Science 306 (5702) 1686
 J. Cook et al. ‘Quanitfying the Consensus on Anthropogenic Global Warming.’ Environmental Research Letters vol8/2 April 2013