Climate Genie is Out of the Bottle
A panel at this year’s American Association for the Advancement of Science (AAAS) meeting was summarized afterwards in a AAAS press release:
Cable news junkies, take heart: if you love wall-to-wall coverage of hurricanes, wildfires and superstorms, your future viewing schedules will be jam-packed.
Researchers at the AAAS Annual Meeting said that wild weather events like Superstorm Sandy and the severe Texas drought are the new normal in North America, as human-driven climate change has made these events more intense and more frequent.
Here’s a quote from one of the speakers (my emphasis):
“The scientific analyses are now indicating a strong link between changing trends in severe weather events and the changing climate,” said Donald Wuebbles, an atmospheric scientist from the University of Illinois. “Every weather event that happens nowadays takes place in the context of a changed background climate.”
In my recent discussion of this popular new frame, I had noted:
we see that every major storm and severe weather event is discussed in the context of climate change.
By no means is this just a U.S. meme. A typhoon that struck the Philippines in December was linked to global warming by the Philippines government and described in the Guardian yesterday as an “ominous warning of climate change impact.” In the piece, Mary Ann Lucille Sering, head of the Philippine government’s climate change commission, said:
Extreme weather is becoming more frequent, you could even call it the new normal.
Indeed, that is what virtually everybody is calling it these days. The climate genie is out of the bottle, in more ways than one.
I seem to remember this being the case after Hurricane Katrina…until after all the ‘new normal’ Hurricane’s failed to materialize.
This reminds me of a conversation with a laundry soap executive I had years ago.
What is ‘new’ in the ‘new’ laundry soap is the word ‘new’ on the box.
Nothing more…nothing less.
Last word on the street was that Bernie Sanders was co-sponsoring a climate bill in the Senate…like somehow Bernie Sanders America’s only socialist senator is somehow near the ‘center of political thought’ in the US…
The ‘messaging’ machine is going full bore as a result.
you’re your own victim. science isn’t political. but just so happens that it endangers the special interest views that have bought & paid for our politicians.
Many of the things that Bernie thinks would be good for the nation are supported by most Americans. He’s only mildly to the left of center in terms of actual public opinion. It’s only in comparison to the narrow terms of discourse allowed by the Village and other Very Serious People that he seems radical.
What has changed with the science since 2008? Did I miss something (being serious)? Back then climate scientists were far from certain that any disaster could be attributed to climate change (see below), and from my recollection, it was considered wrong to do so. Now the POTUS and AAAS seem certain.
From here: http://coast.gkss.de/staff/storch/pdf/GKSS_2010_9.CLISCI.pdf
Question 24: With how much certainty can we attribute recent climate related disasters to climate change?
Mean Response (from 1 to 7): 3.5
Also note that 5X as many respondents said “not at all” compared to “very much”
Responses also lean significantly towards the “not at all” side…
I agree that there is a real danger that some will over-state the causality. However, weather now takes place in a warmer climate system than at any time for millennia so there will be a pervasive, universal effect. Those who argue vehemently against any link between AGW and extreme weather events are obviously mistaken and/or simply engaged in the standard contrarian discourse of denial.
Like these guys?:
Nature | Editorial 19 September 2012
Extreme weather
Better models are needed before exceptional events can be reliably linked to global warming.
http://www.nature.com/news/extreme-weather-1.11428
SUPERSTITION: a belief or practice resulting from a false conception of causation.
Welcome to the new meme.
Nice try asshat! Think you’re posting at a meeting of the Flat Earth Society?
Nature was engaging in a punctual scientific discussion about the need to enhance the reliability of models. They were not engaging in a systematic deception and obfuscation…like you!
Isn’t Sponge Bob on?
Still confusing climate models with statistical analysis of climate behaviour I see. Despite my pointing out your confusion on an earlier thread.
Repeating the wrong argument isn’t going to get you anywhere Buddy.
IGNORANCE: a lack of knowledge.
“There is wide scientific consensus that the increased number and
intensity of climate change induced natural disasters, such as
earthquakes, volcano eruptions, tsunamis and hurricanes, is of alarming
concern,”
Neither the statistical analysis nor the climate models are precise enough to establish the causal relationship between AGW and anecdotal weather events. Sorry if that offends your quasi-religious belief system.
Also applies to wilfully ignoring any facts that conflict with a preconceived belief system. Religious dogma is set in stone. Science is not, concepts evolve as new facts come to light. There are areas of climate science that are definitely not settled, this being one. Quasi-religious dogmatism has no place in real science.
Right about models, dead wrong about statistical analysis of climate behaviour. For example, see the following analyses of the frequency of extreme hot weather events:
Coumou et al. (2013)
Hansen, Sato & Ruedy (2012)
All linked for you last time. You are one of these tedious people who just keeps popping up repeating the previously debunked nonsense aren’t you.
Rhymes with ‘droll’.
I’m not convinced someone who so badly misunderstood (and then serially misrepresented) that Nature editorial is in a position to lecture others as you do here.
It must be true, he’s a lawyer:
http://suyts.wordpress.com/2013/02/15/that-super-sciency-ipcc-strikes-again/
Are you still misrepresenting that Nature editorial, BBD? And the Hansen paper too, I see.
Coumou and Hansen both express information we already knew, that the average temperature has increased slightly over the late 20th century, in a slightly different form that exaggerates the impression to the statistically naive, and draw the same long-debunked conclusion that everyone saw through years ago when they simply plotted the temperature.
The temperature has risen. This has not been demonstrated to be due to AGW.
Attribution is done with climate models. Even the IPCC say so.
It’s true that there are a few fringe contrarians who make this claim. Not many scientists do though. We have to wonder why that is.
Personally, I think it’s either caramelised onions in the stratosphere or increased absorption/re-radiation of thermal IR by black helicopters.
Well, yes, you’re correct except for all the other scientific evidence to the contrary:
Global hurricane activity has decreased to the lowest level in 30 years:http://coaps.fsu.edu/~maue/tropical/global_running_ace.jpg
http://wattsupwiththat.com/2009/03/12/global-hurricane-activity-has-decreased-to-the-lowest-level-in-30-years/
“When the historical record is reviewed, the data reveal there have not been any significant warming-induced increases in extreme weather events.”
http://heartland.org/sites/default/files/05%20Extreme%20Weather.pdf
Unequivocal attribution would require controlled experimentation with the climate system, which
is not possible, The approaches used in detection and attribution research cannot fully account for all uncertainties, and thus ultimately ‘expert judgement’ is required to give a calibrated assessment of whether a specific cause is responsible for a given climate change.
It is the opinion of a number of selected, government-approved IPCC climate scientists that more than half of the late 20th century warming measured globally is due to AGW. It has not been demonstrated in a rigorous scientific manner. It has not been demonstrated for any other climate variable either – including extreme weather, hurricanes, heatwaves, floods, droughts, tornadoes, or, indeed, asteroids, volcanoes, and tsunamis. It’s pure unscientific bunk.
Perhaps we are a little early on in the game, meaning; the message has not yet been delivered with sufficient force to convince people of something as threatening as this. Maybe a half dozen more years of drought in the US, two Katrina sized storms in the same season – a string of disasters like that – will awaken our denial but it is going to have to be on a scale that people have difficulty imagining.
But extremes of hot weather are increasing. We’ll have to wait and see what happens with tropical cyclogenesis, storm intensity and storm tracks over the coming decades. I’d advise keeping an open mind on that. You deplore dogmatism, after all, so be consistent.
I believe the general view is that the frequency of extreme precipitation and drought will rise as warming continues over the C21st. Looking back at the C20th doesn’t tell us much about C21st climate behaviour, which is why Heartland plays these games.
Extreme precipitation and extreme heat events have been something of a feature of the first 13 yeart of the C21st.
Yes. That was the prediction back in 1990, or so.
Evocative, isn’t it? It’s by Professor Michael Oppenheimer, IPCC lead author, twice.
Makes you wonder why all the top researchers in all relevant fields seem convinced that CC is mostly anthropogenic. Do you think it’s a conspiracy?
We’ll have to wait and see yes.
If the model projections are accurate, then these are the sorts of things you might expect to see later on in the century. But it’s neither expected nor observed right now, which is the point.
Since 2008 they learned that you actually couldn’t attribute and it was definitely wrong to do so. The only change is that they’ve decided to do it anyway for political reasons. I’m sure we’ll see apologies any day now to those they used to ridicule with the line “weather isn’t climate” every time we teased them about cold.
Good to know that any weather- hot, cold, wet, dry – is proof of AGW and that all normal weather is now “extreme.” Has to be, otherwise people might notice the falling CS and conclude it’s not “worse than we thought.” In fact, people might turn their attention to piddling, pointless concerns like meteorites exploding with the force of 10 Hiroshimas, drug resistant SARS and TB, energy poverty in Bangladesh and London.
Unless of course if you are writing guff for the Heartland Institute. Why not take this up with Buddy?
Because “top researcher” is defined by the people who do these surveys as “convinced that CC is mostly anthropogenic”.
No, I don’t think it’s a conspiracy.
“Climate” is generally viewed in time frames of at least 30 years, which would make both the flattening in global temperature as well as extreme weather events over the past 13 years statistically questionable. I have an open mind on the subject but not, as Carl Sagan said, having an open mind to the point where your brain falls out. Statistics can always be tortured to eventually confess anything you want them too. I keep that in mind especially when reading news about climate science.
Okay, let’s apply a 30 year running mean to GAT.
I have an open mind on the subject
Versus:
Statistics can always be tortured to eventually confess anything you want them too. I keep that in mind especially when reading news about climate science.
That indicates a deep-seated suspicion of ‘climate science’. You are being contradictory again. Sounds like you think there’s a conspiracy afoot.
Okay, let’s apply a 30 year running mean to GAT.
Yes, of course, nullius. It’s all just circular reasoning and groupthink. No science in there at all. Thank goodness there are a few clear-sighted polymaths out there to set the record straight.
Can someone point me to the evidence that storms such as Sandy have already become more intense and more frequent? I seem to have missed it.
For the record, the AAAS and Hansen stating their expert judgement is not what I call evidence.
Normalized US losses
http://rogerpielkejr.blogspot.com/2012/12/updated-normalized-hurricane-losses.html
Normalized US Hurricane Intensity
http://rogerpielkejr.blogspot.com/2012/11/us-hurricane-intensity-1900-2012.html
Global Tropical Cyclone Landfalls
http://rogerpielkejr.blogspot.com/2012/12/global-tropical-cyclone-landfalls-2012.html
The US Intense Hurricane Drought
http://rogerpielkejr.blogspot.com/2012/05/updated-us-intense-hurricane-drought.html
Global Hurricane Frequency
http://policlimate.com/tropical/global_major_freq.png
Global Accumulated Cyclone Energy
http://policlimate.com/tropical/global_running_ace.png
Meanwhile, reality refuses to obey the wishful thinking
http://thinkprogress.org/climate/2013/02/14/1594211/death-spiral-bombshell-cryosat-2-confirms-arctic-sea-ice-volume-has-collapsed/
My new paper is now online …
ABSTRACT
The paper explains why the physics
involved in atmospheric and sub-surface heat transfer appears to have
been misunderstood, and incorrectly applied, when postulating that a
radiative “greenhouse effect” is responsible for warming the
surfaces of planets such as Venus and our own Earth.
A detailed discussion of the
application of the Second Law of Thermodynamics endeavours to settle
the much debated issue as to whether or not a thermal gradient
evolves spontaneously in still air in a gravitational field. The
author is aware of attempted rebuttals of this hypothesis, but cogent
counter arguments are presented, together with reference to empirical
evidence.
The ramifications are substantial,
in that they eliminate any need for any “greenhouse” explanation
as to why the surface temperatures are as observed. No other valid
reason appears plausible to explain how the required energy gets into
the planetary surfaces, this being especially obvious in regard to
the high temperatures measured at the surface of the crust of Venus.
The paper includes some
counter-intuitive concepts which sceptical readers may be tempted to
reject out of hand. Physics sometimes has some surprises, and so you
are encouraged to read and understand the argument step by step, for
it is based on sound physics, and unlocks some mysteries of the Solar
System, including core and mantle temperatures, not previously
explained in this manner to the best of the author’s knowledge.
http://principia-scientific.org/publications/PROM/PROM-COTTON_Planetary_Core_and_Surface_Temperatures.pdf
Hi Doug! Are you still trying to sell that tired old nonsense? Still, I guess it’s something to keep yourself eternally occupied with. 🙂
What do you think of the subject of the post? Is the ‘new normal’ new, or normal? How could you tell?
Coming from an expert on the subject. How about the IPCC instead? “There is medium evidence and high agreement that long-term trends in normalized losses have not been attributed to natural or anthropogenic climate change,” writes the IPCC in its new Special Report on Extremes (SREX) published today.
“The statement about the absence of trends in impacts attributable to natural or anthropogenic climate change holds for tropical and extratropical storms and tornados,” the authors conclude, adding for good measure that “absence of an attributable climate change signal in losses also holds for flood losses”.
I believe the general view is that the frequency of extreme
precipitation and drought will increase as warming continues over the C21st. Looking back at the C20th doesn’t tell us much about C21st climate behaviour, which is why Tom Fuller and Heartland play these games.
Extremes of hot weather are increasing. We’ll have to wait and see what happens over the coming decades. I’d advise keeping an open mind on that.
Especially as extreme precipitation and extreme heat events have been something of a feature of the first 12 years of the C21st.
Science is dead.
Climate kooks are in full bloom, and it is entertaining to watch as the weather continues to ignore their rants and assertions. As climate continues to progress without storm frequency, drought intensity, rain, snow tornadoes, etc. not behaving as claimed, we will see more and more of this sort of reliance and cheesy and deceitful metaphors. The climate concerned are more and more the climate crazed. Obsession does not mean informed or correct. But it does mean obsessed. And the cliamte concerned are nothing if not obsessed. Thanks for highlighting such good examples of this.
peter, if it is failing due to marketing, which is what you are referring to, it has already failed.
Long live carbonaceous chondrites and bat-grease frittattas!
What is that from? If no link, then some kind of citation would be appreciated
It’s from the first chapter of the book “Dead heat: the race against the greenhouse effect”. The first chapter is amusingly titled “The End” and gives a fictional retrospective as if from the year 2050. It says in the end notes that it is based on the real predictions of science, and urgent cuts in emissions might delay it by as much as 10 years (IIRC).
http://books.google.co.uk/books/about/Dead_heat.html?id=PwX16f6jL0AC&redir_esc=y
It’s quite nicely written. And given that it’s obviously based on the history of the dustbowl, distinctly plausible. It’s only hindsight that distinguishes it from the sort of things we read today.
Nullis,
Your first paragraph is reaonable enough, but “expert judgement” is not the same as “opinion”.
I feel like debating on the question whether spring is here or not. One sunny warm day is enough to prove it or is it a certain number of subsequent sunny days are needed to fully be sure that it is spring now? If yes how many? I hope you see the difficulty in this kind of approach. I say the weather (and the climate) is obviously changing, if you want to call it spring or not, your choice.
Agreed, Bernie’s ideas (universal health care, higher wages, protect the environment) are in line with what the average Joe wants. The only problem is, how to pay for it? And that is the crux of the issue.
The masses want plenty of things (Vaca to Hawaii every year? Retire at 55? Sure!) that are not practical. The hope is that political leaders can plot the way to the best outcome achievable for the citizenry. Sadly, all sides (Repubs, Dems, and yes even Socialists) are failing miserably in their inability to rationally discuss our present situation & options for the future.
Tom Scharf
The trick is to read the other comments. It’s a simple, easy way of avoiding posting redundant junk. If you had read the thread, you would have spotted the following ‘pre-answer’ to your question, which I have lightly edited in acknowledgement of your contribution here:
“I believe the general view is that the frequency of extreme precipitation and drought will increase as warming continues over the C21st. Looking back at the C20th doesn’t tell us much about C21st climate behaviour, which is why Tom Scharf, Tom Fuller and Heartland play these games.
Extremes of hot weather are increasing. We’ll have to wait and see what happens over the coming decades. I’d advise keeping an open mind on that.
Especially as extreme precipitation and extreme heat events have been something of a feature of the first 12 years of the C21st.”
Both universal healthcare — especially some form of single-payer — and protecting the environment cost less overall than the alternatives, and less income inequality results in a more robust economy for everyone, even if a few folks at the top may have to sell their Hawaii vacation homes and maybe even work for a living rather than live off investments on their parents’ wealth. The question isn’t whether we as a country can afford these things, but whether we’re allowed to. Or even whether we’re able to discuss them without being brushed off by those who benefit most from the current screwed-up systems.
Doesn’t look like we’re sliding back into a glacial to me Daniel… Rather the opposite in fact.
What’s the difference?
Right. That’s not what I meant, ice age was just an example (see it was in brackets:).
Hasn’t every weather event taken place against a background of a changed background climate?
Couldn’t you have said the same thing in the 1930’s or the 1970’s?
Is this a useful meme?
I don’t follow your reasoning. There are mechanisms that cause the change in seasons. There are mechanisms that cause the onset and termination of glacials. There are mechanisms that cause energy to accumulate in the climate system as it has evidently been doing for many decades. I’m surprised to see such a lack of curiosity about cause and effect in a doctoral student of physics. But perhaps I am missing your point?
“Expert judgement” is a view based on consideration of the evidence backed up by knowlege and experience of the subject in question.
An “opinion”, at least as commonly used, is a much more wooly concept, based to a large extent on personal taste and prejudice – thus opinion polls generally tell us about the personal preferences of those polled but very little about the “truth” about the subject in question.
Maybe you weren’t using the word in that sense and I misinterpreted you, but that’s the way it came across to me.
“Consideration of the evidence” says that unequivocal attribution is impossible and the approaches used in research cannot fully account for the uncertainties.
So if you’re concluding something else, it’s not originating in consideration of the evidence. That part that goes beyond what the evidence can strictly support is opinion. It may be the opinion of an expert with knowledge and experience, but if that knowledge was sufficient on its own they would have said so.
You are right that this may be an argument more about the impression a word conveys rather than any strict definition. (I definitely didn’t mean it in the sense of ignorant opinion, the product of nothing but personal taste and prejudice.) The phrase “expert judgement” is chosen for the impression it gives – in much the same way I chose the word “opinion” because it means the same thing while giving a completely different impression – one that better reflects my opinion (or “expert judgement” if you prefer). And yes, I did do it deliberately.
Therein lies the difference of opinion, you see? 🙂
Now all the sceptics have to do is explain why CO2 forcing is less efficacious than paleoclimate evidence very strongly suggests *and* explain the mystery forcing responsible for the warming misattributed to CO2.
Then we’d have something a little more substantial to go on than insinuating that the whole thing is groupthink infected with non-libertarian physics 😉
That’s easy. We just point out that paleoclimate only weakly suggests, and that there’s no evidence to say the warming is due to a forcing.
I wasn’t insinuating anything. Just emphasising the line between what the scientific evidence supports, and what the IPCC experts believe as a matter of their IPCC expert opinion.
nullius
Are you suggesting that we should inject french onion soup into the stratosphere to avoid the looming snowball earth?
oh and just so you know, my IR black helicopter shoots missiles 🙂
If that is you, you need a more comfortable chair.
But joking aside, I object to your misrepresentation of what I said. Caramelised onions are only an ingredient of this ‘french onion soup’ stuff you think is teh answer.
And you didn’t address my point about the effect of black helicopter loading on the radiative profile of the lower troposphere. As ever, you dodge.
I do love it when you quote stuff without understanding it! 🙂
So you’re saying the paleoclimate evidence gives a 95% interval between 1.1 C and 7.0 C per doubling, right? And it doesn’t even include the methodological uncertainty. That sounds like “weakly suggests” to me.
It is weakly suggestive.
The one-sigma trick is cute, but is clearly designed to disguise their inability to meaningfully bound the uncertainty about climate sensitivity, which is itself a concise summary of our knowledge of the connection between CO2 and warming. The numbers say there is no hard evidence of a connection. Everything else is opinion and conjecture.
Earlier you lied about me misrepresenting something. Now you are lying about me not understanding something. You make these cheap shots to make cheap rhetorical gains. It’s a crass, self-serving dishonesty that works against you in the long run.
The uncertainty is greater because the Rohling study deals with estimates from across the entire Cenozoic. Focussing on the LGM yields a rather less uncertain result (Hansen & Sato 2012).
Interestingly, Hansen’s own paper that came out of the PALAEOSENS project found S to be around 3C. Preprint here.
The problem here is that going round claiming that there’s sooo much uncertainty and ‘it’s all just opinion’ while failing to explain the reasons why CO2 forcing is less efficacious that expected and what mystery forcing caused modern warming is just making a hollow, contrarian noise.
You need something a great deal more solid before anyone’s going to take you seriously. Starting with me.
The one-sigma trick is cute, but is clearly designed to disguise their inability to meaningfully bound the uncertainty about climate sensitivity, which is itself a concise summary of our knowledge of the connection between CO2 and warming. The numbers say there is no hard evidence of a connection.
So explain the overall ~ 50Ma cooling trend since the Eocene optimum without invoking CO2 forcing.
Hansen & Sato (2012) quantifies estimated forcing changes over this period and finds that CO2 was *by far* the largest. HS12 concludes that the broad trend in Cenozoic climate change is only explicable if the reduction in CO2 forcing over the last ~50Ma was taken into account.
Everything you insinuate is weak, nullius. It’s not the mainstream scientific position that is weak. You are projecting like a fire hose.
BBD, I know very well that you’ll never take me seriously, any more than I take you seriously. I do this just for the fun of it.
More data over a longer period ought to give more accurate results, not less. (Unless the statistical model is misspecified, that it.)
Even the mainstreamers of the IPCC don’t pretend that the evidence constrains sensitivity very much. We simply don’t know. And they have to use weasel tricks like quoting one-sigma bounds in order to avoid making their “expert judgements” look ridiculous. The burden of proof is on climate scientists to show the connection.
John Locke, An Essay Concerning Human Understanding, 1689.
So explain the overall cooling since the Eocene optimum, as I have invited you to do already. Your somewhat paranoid conjectures about the motivations of climate science are interesting, but not in the way you intend.
Of course we can’t make an “unequivocal” attribution, that doesn’t mean we can’t make one with a high level of confidence based on consideration of the evidence. I don’t think anyone has claimed to know with absolute certainty how much of recent warming is due to CO2 so your arguing against a strawman.
Sure. Just give me the precise daily global weather data, atmospheric and ocean circulation, and ocean (bio-)chemistry down to the lysocline at a 1 km grid resolution for a representative period back then, and I’ll be happy to look at the question for you.
We don’t even know why stuff happens today, with satellites and buoys and survey vessels and whatnot. You want me to diagnose the climate back in 55 million years BC?! With virtually no data?
Argumentum ad ignorantiam.
Evasion. Either point to the errors in the HS12 analysis or admit that you can’t and explain why you reject it anyway.
Because they use models to extrapolate a tiny number of proxy spot observations out to a global average temperature, then they use physical models to estimate the forcing exerted by those few elements of the climate they can estimate from proxies, and finally they divide one number by the other. All the unknowns they completely ignore.
It’s a joke. We can’t even measure it that accurately with satellites, we can’t even tell if the medieval warm period was warmer a mere thousand years ago, and you want to tell me you can somehow get a more accurate figure from 20,000 years ago? Be serious!
Hansen does it because he’s a fruit-loop climate activist who is very well paid for his activities, but everyone else in the business knows to pay no attention, and the IPCC still says ‘nobody knows’. Nobody does.
Instead of a detailed critique of the methodology and referenced studies in HS12 you provide the usual substanceless blanket denial of the validity of everything followed by an ad-hominem against Hansen. You then misrepresent the IPCC for good measure. The IPCC does *not* say ‘nobody knows’. It says:
Since the TAR, the levels of scientific understanding and confidence in quantitative estimates of equilibrium climate sensitivity have increased substantially. Basing our assessment on a combination of several independent lines of evidence, as summarised in Box 10.2 Figures 1 and 2, including observed climate change and the strength of known feedbacks simulated in GCMs, we conclude that the global mean equilibrium warming for doubling CO2, or ‘equilibrium climate sensitivity’, is likely to lie in the range 2°C to 4.5°C, with a most likely value of about 3°C. Equilibrium climate sensitivity is very likely larger than 1.5°C.
The general view nowadays is that the contrarians are the ‘fruit-loop climate activists’. Which is why they are not taken seriously.
And the IPCC interpretation of “likely” is one-sigma – i.e. the exact same trick you missed up above. And virtually all of that “several independent lines of evidence” is “because the models say so” and not independent at all.
They wrap it around with more weasel words, but it’s still what they say, and what they write buried in the depths of the report. Plus, the smell is getting even worse with the latest data and results. But not to worry. Everyone knows that when the predictions don’t come true, you just move the predictions, and say the science has moved on. It’s just a matter of time.
Tricks, weasel words, worsening smell…
Yes dear.
I think Michael Tobis may have coined the term ‘climate agnosia’ for this behaviour. Whoever it was, they were spot on.
Precipitation and drought trends increased during the C20th even though the effects of CO2 forcing only began to emerge at the end of the century. Perhaps we should keep an open mind at this stage:
Dai (2012) Increasing drought under global warming in observations and models
Donat et al. (2013) Updated analyses of temperature and precipitation extreme indices since the beginning of the twentieth century: The HadEX2 dataset
Westra et al. (2012) Global increasing trends in annual maximum daily precipitation
“confidence” – that’s like “uncertainty” isn’t it? The approaches used in detection and attribution research cannot fully account for all uncertainties. Thus, the evidence cannot say.
Lots of people – most of them not scientists – have claimed that the science on CO2 causing the warming is unquestionable, and the impression commonly given is that all of the warming is a consequence of CO2. People certainly point to shifts in the distribution post-1998 and draw the connection.
Scientists are usually – not always – more careful. But we always get this dual picture. Non-scientists put out some nonsensical scary story, connecting weather to climate or observed warming to CO2 or whatever. We object, saying it’s wrong to say such and such. We get told that nobody ever said that, and referred to the peer-reviewed science.
But you see, this is exactly what I’m saying here! The mainstream science is that sensitivity is poorly contrained by the empirical evidence, most of the results in this area are derived (directly or indirectly) from climate models, the climate models are wrong, although nobody knows if they’re wrong enough to matter, and thus the conclusion is a matter of educated guesswork on the part of people whose careers and importance are founded on the answer being thus. Nobody is saying how much of recent warming is due to CO2, because nobody knows.
However, people’s causes and careers rely on maintaining the impression that they do, which is why they complain when I say the same thing in terms that could give the ‘wrong’ impression. Carefully phrased statements with subtle ambiguities and unintuitive definitions are trotted out. There is evidence, that scientists acknowledge is not definitive, but by sitting in its presence some of its authority rubs off somehow on the “expert judgements” that a bunch of them sitting around a table somewhere make.
Fine. Well prove it. Articulate your expert reasoning into terms we can all understand, quantify it numerically, so we know how you calculated that likelihood level. We’re not employing you to tell us the answer, we’re employing you to explain it.
Here’s what the IAC report said:
“The IPCC uncertainty guidance urges authors to provide a traceable account of how authors
determined what ratings to use to describe the level of scientific understanding (Table 3.1) and
the likelihood that a particular outcome will occur (Table 3.3). However, it is unclear exactly
whose judgments are reflected in the ratings that appear in the Fourth Assessment Report or how
the judgments were determined. How, exactly, a consensus was reached regarding subjective
probability distributions needs to be documented. The uncertainty guidance for the Third
Assessment Report required authors to indicate the basis for assigning a probability to an
outcome or event (Moss and Schneider, 2000), and this requirement is consistent with the
guidance for the Fourth Assessment Report.”
“IPCC’s guidance for addressing uncertainties
in the Fourth Assessment Report urge authors to consider the amount of evidence and level of
agreement about all conclusions and to apply subjective probabilities of confidence to
conclusions when there was “high agreement, much evidence.” However, such guidance was not
always followed, as exemplified by the many statements in the Working Group II Summary for
Policy Makers that are assigned high confidence, but are based on little evidence. Moreover, the
apparent need to include statements of “high confidence” (i.e., an 8 out of 10 chance of being
correct) in the Summary for Policy Makers led authors to make many vaguely defined statements
that are difficult to refute, making them therefore of “high confidence.” Such statements have
little value.”
And so on. It shouldn’t be a controversial point. If you’ve got evidence for a statement, then show it. If you don’t have sufficient evidence, then don’t say it. We’re not interested in your opinions. When you make a quantified statement of confidence, we want to see how it was calculated. “Expert judgement” is not an answer.
But this is the new normal, though. Post-normal science, they call it.
NiV,
“confidence” – that’s like “uncertainty” isn’t it? The approaches used in detection and attribution research cannot fully account for all uncertainties.
Well obviously the level of uncertainty will have a bearing on the level of confidence which we have in our conclusions. But you can’t just frame the argument in terms of uncertainties – it’s also about what we do know. Just saying there are uncertainties therefore we can’t reach any conclusion is not necessarily true, you have to demonstrate that they are significant enough to undermine the conclusions we have drawn from the evidence we do have, otherwise it’s just handwaving. So for example, sensitivity is not tightly constrained, but there still are constraints at the bottom end and even the lower end of our estimates is still consistent with CO2 causing most of the warming we have seen. And the limitations of the models don’t nullify our understanding of the radiative properties of CO2 or alter the fact that the other known influences on our climate can’t account for the warming (nor do they particularly suggest there are likely to be significant hitherto unknown influences).
Lots of people – most of them not scientists – have claimed that the science on CO2 causing the warming is unquestionable
The science which says that adding CO2 to the atmosphere will cause warming is extremely well established, and even a conservative estimate of the amount of warming we would expect given the increases in CO2 we have seen is sufficient to explain most, if not all, of the warming we have seen so far. So as a non-scientist’s perspective, and in the absence of any specific examples of things people have actually said, I don’t think it’s unreasonable to say that CO2 is the major factor in the warming we have seen in recent decades. Of course on this, as on any issue, you will find example of people overstating their case, the extent to which that matters in particular instance depends on the perceived influence and authority of the person in question. One would naturally expect scientists to be more cautious in their choice of words and, as you say, they usually are. Your claim that peopel are overstating their certainty because their careers somehow depend on it is just an assertion for which you have not provided any evidence.
As for the IPCC, their attribution statement is actually very conservative, and I think that the basis on which they have made this judgement is pretty clear from what is contained in WGI in general, and that’s what it should be judged against. Details of the deliberations which led them to use a specific wording might be interesting to some, and if it is in their guidelines to provide such information then they should do so, but it’s not of much interest to me.
I agree with most of that.
I agree that mainstream science sets bounds at the lower end. I’ll not argue with that, since it would take us too far afield and distract from the point. I agree that the lower bound is consistent with CO2 causing most of the warming. It’s also not far off what most sceptics say.
I agree that science’s understanding of the radiative properties of CO2 are not nullified, but they’re not the issue. (And very few of those arguing for climate action understand those properties and their implications either. The greenhouse effect is more complicated than you’d think.)
I’m not convinced of the case for saying the other known influences on climate can’t account for the warming. If you mean those factors included in the climate models, I agree. But then they can’t account for the tropical upper troposphere temperatures, precipitation variance, observed humidity, the Arctic sea ice melt, the frequency or magnitude of ENSO, or regional climate details, so I’m not sure if that tells us anything. There are other proposals that, for certain values of unknown parameters, could account for it, in a rough-order-of-magnitude sort of way. We don’t know that climate does work that way, but we don’t know that it doesn’t, either. So it depends on exactly what you mean by “can’t account for”.
Mostly the reason climate models don’t is because nobody has tried very hard.
It’s true that the science which says adding CO2 to the atmosphere will contribute a warming effect is well-established. Whether it will result in actual warming depends on its magnitude compared to all the other contributors, neither of which is known. I agree it’s probable, but the science isn’t as clear on the matter as some people think.
And I agree that the IPCC’s statement of at least half the warming between 1950 and 2000 being due to anthropogenic CO2 is quite likely. It’s a bit questionable if you can divide up responsibility into fractions like that when you’re talking about a non-linear phenomenon with both positive and negative contributions, but that’s mostly a language problem.
And I agree that it’s actually very conservative, which again is my main point. If you parse what they say sufficiently strictly, the caveats and limitations are there, and the picture is a much less scary one.
It’s mostly when the activists read it less carefully, paraphrase it loosely, and draw out implications that aren’t really there that it all goes wrong. This “new normal” of connecting weather to climate is one example. The science says you can’t do that, but people still do. The science says we can’t constrain temperature well enough to predict huge temperature rises, but people still do. People on both sides routinely go beyond what the science allows you to say, but only one side get demonised by the mainstream establishment as anti-science cranks in the pay of special interests. Climate scientists have done it too. You get these two separate stories, one dramatic and hysterical, the other cautious and measured, and people mix them up.
I’m all in favour of the cautious and measured picture you’re presenting. I’m just pointing out that it’s not the only one being presented.
Where I am, the temperature today is a bit below average. Nevertheless, the weather is extremely nice today.
With global climatic change, I hope that ‘extremely nice’ will be the new normal.