“There is no such thing as consensus science. If it’s consensus, it isn’t science. If it’s science, it isn’t consensus. Period.”
“I would remind you to notice where the claim of consensus is invoked. Consensus is invoked only in situations where the science is not solid enough. Nobody says the consensus of scientists agrees that E=mc2. Nobody says the consensus is that the sun is 93 million miles away. It would never occur to anyone to speak that way.”
“Historically, the claim of consensus has been the first refuge of scoundrels; it is a way to avoid debate by claiming that the matter is already settled. Whenever you hear the consensus of scientists agrees on something or other, reach for your wallet, because you’re being had.”
― Michael Crichton
A cooling consensus
GLOBAL warming has slowed. The rate of warming of over the past 15 years has been lower than that of the preceding 20 years. There is no serious doubt that our planet continues to heat, but it has heated less than most climate scientists had predicted. Nate Cohn of the New Republic reports: “Since 1998, the warmest year of the twentieth century, temperatures have not kept up with computer models that seemed to project steady warming; they’re perilously close to falling beneath even the lowest projections”.
Mr Cohn does his best to affirm that the urgent necessity of acting to retard warming has not abated, as does Brad Plumer of the Washington Post, as does this newspaper. But there’s no way around the fact that this reprieve for the planet is bad news for proponents of policies, such as carbon taxes and emissions treaties, meant to slow warming by moderating the release of greenhouse gases. The reality is that the already meagre prospects of these policies, in America at least, will be devastated if temperatures do fall outside the lower bound of the projections that environmentalists have used to create a panicked sense of emergency. Whether or not dramatic climate-policy interventions remain advisable, they will become harder, if not impossible, to sell to the public, which will feel, not unreasonably, that the scientific and media establishment has cried wolf.
Dramatic warming may exact a terrible price in terms of human welfare, especially in poorer countries. But cutting emissions enough to put a real dent in warming may also put a real dent in economic growth. This could also exact a terrible humanitarian price, especially in poorer countries. Given the so-far unfathomed complexity of global climate and the tenuousness of our grasp on the full set of relevant physical mechanisms, I have favoured waiting a decade or two in order to test and improve the empirical reliability of our climate models, while also allowing the economies of the less-developed parts of the world to grow unhindered, improving their position to adapt to whatever heavy weather may come their way. I have been told repeatedly that “we cannot afford to wait”. More distressingly, my brand of sceptical empiricism has been often met with a bludgeoning dogmatism about the authority of scientific consensus.
Of course, if the consensus climate models turn out to be falsified just a few years later, average temperature having remained at levels not even admitted to be have been physically possible, the authority of consensus will have been exposed as rather weak. The authority of expert consensus obviously strengthens as the quality of expertise improves, which is why it’s quite sensible, as matter of science-based policy-making, to wait for a callow science to improve before taking grand measures on the basis of its predictions.
Anyway, Mr Cohn cites a few scientists who are unruffled by the surprisingly slow warming.
It might seem like a decade-long warming plateau would cause a crisis for climate science. It hasn’t. Gerald Meehl, a Senior Scientist at the National Center for Atmospheric Research, has seen hiatus periods before. They “occur pretty commonly in the observed records,” and there are climate models showing “a hiatus as long as 15 years.” As a result, Isaac Held, a Senior Research Scientist at NOAA’s Geophysical Fluid Dynamics Laboratory, says “no one has ever expected warming to be continuous, increasing like a straight line.” Those much-cited computer models are composed of numerous simulations that individually account for naturally occurring variability. But, Meehl says, “the averages cancel it out.”
Isn’t this transparently ad hoc. The point of averaging is to prune off exceedingly unlikely possibilities. It does not vindicate a model to note that it gives no weight—that it “cancels out”—its only accurate constitutive simulations.
If “hiatus periods are commonly observed” is the right way to think about the current warming plateau, then the rest of Mr Cohn’s article, examining various explanations of the puzzle of the hiatus would be unnecessary. But, as all the pieces discussing the warming plateau make perfectly clear, climate scientists are actually pretty baffled about the failure of their predictions. Is it the oceans? Clouds? Volcanoes? The sun? An artifact of temperature data?
As a rule, climate scientists were previously very confident that the planet would be warmer than it is by now, and no one knows for sure why it isn’t. This isn’t a crisis for climate science. This is just the way science goes. But it is a crisis for climate-policy advocates who based their arguments on the authority of scientific consensus. Mr Cohn eventually gets around to admitting that
In the end, the so-called scientific consensus on global warming doesn’t look like much like consensus when scientists are struggling to explain the intricacies of the earth’s climate system, or uttering the word “uncertainty” with striking regularity.
But his attempt to minimise the political relevance of this is unconvincing. He writes:
The recent wave of news and magazine articles about scientists struggling to explain the warming slowdown could prolong or deepen the public’s skepticism.
But the “consensus” never extended to the intricacies of the climate system, just the core belief that additional greenhouse gas emissions would warm the planet.
If this is true, then the public has been systematically deceived. As it has been presented to the public, the scientific consensus extended precisely to that which is now seems to be in question: the sensitivity of global temperature to increases in atmospheric carbon dioxide. Indeed, if the consensus had been only that greenhouse gases have some warming effect, there would have been no obvious policy implications at all. As this paper has maintained:
If … temperatures are likely to rise by only 2°C in response to a doubling of carbon emissions (and if the likelihood of a 6°C increase is trivial), the calculation might change. Perhaps the world should seek to adjust to (rather than stop) the greenhouse-gas splurge. There is no point buying earthquake insurance if you do not live in an earthquake zone. In this case more adaptation rather than more mitigation might be the right policy at the margin. But that would be good advice only if these new estimates really were more reliable than the old ones. And different results come from different models.
We have not been awash in arguments for adaptation precisely because the consensus pertained to now-troubled estimates of climate sensitivity. The moralising stridency of so many arguments for cap-and-trade, carbon taxes, and global emissions treaties was founded on the idea that there is a consensus about how much warming there would be if carbon emissions continue on trend. The rather heated debates we have had about the likely economic and social damage of carbon emissions have been based on that idea that there is something like a scientific consensus about the range of warming we can expect. If that consensus is now falling apart, as it seems it may be, that is, for good or ill, a very big deal.
“It doesn’t matter what is true,
it only matters what people believe is true.”
– Paul Watson,
co-founder of Greenpeace
“We’ve got to ride this global warming issue.
Even if the theory of global warming is wrong,
we will be doing the right thing in terms of
economic and environmental policy.“
– Timothy Wirth,
President of the UN Foundation
“As we all know, this isn’t about truth at all, its about plausibly deniable accusations.”
“The data doesn’t matter. We’re not basing our recommendations
on the data. We’re basing them on the climate models.”
– Prof. Chris Folland,
Hadley Centre for Climate Prediction and Research
Jimbo on Watts Up With That rounds up the climate scientists confessing to this lack of warming:
Dr. Phil Jones – CRU emails – 5th July, 2005
“The scientific community would come down on me in no uncertain terms if I said the world had cooled from 1998. OK it has but it is only 7 years of data and it isn’t statistically significant….”
Dr. Phil Jones – CRU emails – 7th May, 2009
‘Bottom line: the ‘no upward trend’ has to continue for a total of 15 years before we get worried.’
Dr. Judith L. Lean – Geophysical Research Letters – 15 Aug 2009
“…This lack of overall warming is analogous to the period from 2002 to 2008 when decreasing solar irradiance also countered much of the anthropogenic warming…”
Dr. Kevin Trenberth – CRU emails – 12 Oct. 2009
“Well, I have my own article on where the heck is global warming…..The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t.”
Dr. Mojib Latif – Spiegel – 19th November 2009
“At present, however, the warming is taking a break,”…….”There can be no argument about that.”
Dr. Jochem Marotzke – Spiegel – 19th November 2009
“It cannot be denied that this is one of the hottest issues in the scientific community…. We don’t really know why this stagnation is taking place at this point.”
Dr. Phil Jones – BBC – 13th February 2010
“I’m a scientist trying to measure temperature. If I registered that the climate has been cooling I’d say so. But it hasn’t until recently – and then barely at all. The trend is a warming trend.”
Dr. Phil Jones – BBC – 13th February 2010
[Q] B – “Do you agree that from 1995 to the present there has been no statistically-significant global warming”
[A] “Yes, but only just”.
Prof. Shaowu Wang et al – Advances in Climate Change Research – 2010
“…The decade of 1999-2008 is still the warmest of the last 30 years, though the global temperature increment is near zero;…”
Dr. Robert K. Kaufmann – PNAS – 2nd June 2011
“…..it has been unclear why global surface temperatures did not rise between 1998 and 2008…..”
Dr. Gerald A. Meehl – Nature Climate Change – 18th September 2011
“There have been decades, such as 2000–2009, when the observed globally averaged surface-temperature time series shows little increase or even a slightly negative trend1 (a hiatus period)….”
Met Office Blog – Dave Britton (10:48:21) – 14 October 2012
“We agree with Mr Rose that there has been only a very small amount of warming in the 21st Century. As stated in our response, this is 0.05 degrees Celsius since 1997 equivalent to 0.03 degrees Celsius per decade.”
Dr. James Hansen – NASA GISS – 15 January 2013
“The 5-year mean global temperature has been flat for a decade, which we interpret as a combination of natural variability and a slowdown in the growth rate of the net climate forcing.”
Dr. Virginie Guemas – Nature Climate Change – 7 April 2013
“…Despite a sustained production of anthropogenic greenhouse gases, the Earth’s mean near-surface temperature paused its rise during the 2000–2010 period…”
Dr. Hans von Storch – Spiegel – 20 June 2013
“…the increase over the last 15 years was just 0.06 degrees Celsius (0.11 degrees Fahrenheit) — a value very close to zero….If things continue as they have been, in five years, at the latest, we will need to acknowledge that something is fundamentally wrong with our climate models….”
Professor Masahiro Watanabe – Geophysical Research Letters – 28 June 2013
“The weakening of k commonly found in GCMs seems to be an inevitable response of the climate system to global warming, suggesting the recovery from hiatus in coming decades.”
Professor Rowan Sutton – Independent – 22 July 2013
“Some people call it a slow-down, some call it a hiatus, some people call it a pause. The global average surface temperature has not increased substantially over the last 10 to 15 years.”
Scientists have long been aware that climate change would not happen at a fixed rate and could include periods where temperatures remain stable for 10 to 20 years, but admitted they had failed to explain this to the public in the past.
Prof Rowan Sutton, Director of Climate Research at the University of Reading, said: “Within the field we have taken for granted that there will be variations in the rate of warming, it is totally accepted and is no surprise …[it] would correct to say that wasn’t the message that we communicated more widely and that probably is a failing.”
Prof Sutton Translation:
“Within the field we have taken for granted that
there will be variations in the rate of warming mother nature is killing our global warming theory/scam, it is totally accepted unacceptable and is no a BIG surprise …[it] would correct to say that wasn’t the message that we communicated more widely and that probably is a failing.” (We have no idea what we are talking about, but if we keep lying about climate catastrophe, funding will continue and our jobs secure.)
Satellite temperature records on six different data sets show that there has been no atmospheric global warming since 1998 or any statistically-significant warming for between 18 and 23 years. A distinct lack of any warming evident, despite a dramatic rise in industrial greenhouse gas emissions over the same period:
More Peer-Reviewed studies that confirm the lack of any recent global warming:
- Reconciling anthropogenic climate change with observed temperature 1998–2008
- Retrospective prediction of the global warming slowdown in the past decade
- Overestimated global warming over the past 20 years – Nature Climate Change 28/8/2013
- Warmist scientists talk about no Global Warming