Summary: Climate scientist Garth Paltridge takes us on a tour behind the scenes of the IPCC’s new special report about the dangers of global warming over the 1.5°C red line.
“Climate’s Uncertainty Principle“
By Garth Paltridge at Quadrent, April 2019 issue.
Reposted from Climate Etc under their creative commons license.
Graphics and links added.
A look behind the scenes at the IPCC’s Special Report: Global Warming of 1.5 ºC.
Whether we should do anything now to limit our impact on future climate boils down to an assessment of a relevant cost-benefit ratio. That is, we need to put a dollar number to the cost of doing something now, a dollar number to the benefit thus obtained by the future generations, and a number to a thing called “discount for the future” – this last being the rate at which our concern for the welfare of future generations falls away as we look further and further ahead. Only the first of these numbers can be estimated with any degree of reliability.
Suffice it to say, if the climate-change establishment were to have its way with its proposed conversion of the global usage of energy to a usage based solely on renewable energy, the costs of the conversion would be horrifically large. It is extraordinary that such costs can even be contemplated when the numbers for both the future benefit and the discount for the future are little more than abstract guesses.
Numerical models.
Assessment of the future benefit is largely based on two types of numerical modelling. First, there are the vast computer models that attempt to forecast the future change in Earth’s climate when atmospheric carbon dioxide has increased as a consequence of the human activity of burning fossil fuel. Second, there are the computer-based economic models which attempt to calculate the economic and social impact of the forecasted change of climate. {Editor note: DICE models.} Reduction of that impact (by reducing the human input of carbon dioxide to the atmosphere) is the “benefit” in the cost-benefit calculations.
Taking the climate change calculations first, it should be emphasised that in order to be really useful, the forecast must necessarily be of the future distribution of climate about the world – on the scale of areas as small as individual nations and regions. Calculating only the global average of such things as the future temperature and rainfall is not useful. The economic models need input data relevant to individual nations, not just the world as a whole.
Which is a bit of a problem. The uncertainty associated with climate prediction derives basically from the turbulent nature of the processes going on within the atmosphere and oceans. Such predictability as there is in turbulent fluids is governed by the size (the “scale”) of the boundaries that contain and limit the size to which random turbulent eddies can grow. Thus reasonably correct forecasts of the average climate of the world might be possible in principle. On the scale of regions (anything much smaller than the scale of the major ocean basins for example) it has yet to be shown that useful long-term climate forecasting is possible even in principle.
To expand on that a little, the forecasts of the global average rise in temperature by the various theoretical models around the world range from about 1° to 6° Celsius by the end of this century – which does little more than support the purely qualitative conclusion from simple physical reasoning that more carbon dioxide in the atmosphere will increase the global average temperature above what it would have been otherwise. It does little to resolve the fundamental question as to what fraction of the observed rise in global surface temperature over the last thirty or so years (equivalent to a rise of about 1° Celsius per century if one is inclined to believe observations rather than the theory) is attributable to the human-induced increase in atmospheric carbon dioxide.
There is still a distinct possibility that much of the observed rise in global temperature may be the result of natural (and maybe random) variability of the system.
While the forecasts of future global average climate are not really trustworthy and would probably not be very useful even if they were, the potentially much more useful forecasts of regional climates are perhaps just nonsense. A good example supporting this rather negative view of the matter is the variability of the set of hundred-year forecasts of the average rainfall over Australia. Each forecast was produced by one of the many climate models from around the world. The present-day measured average is about 450 millimetres per year. The forecasts for the next century range from less than 200 mm to more than 1000 mm per year. That sort of thing makes finding a model to support a particular narrative just too easy.
As a consequence, the economic models of the future of regions and nations are highly unreliable if only because their regional and national inputs of forecasted climatic “data” are unreliable. But to make matters vastly worse, the economic models themselves are almost certainly useless over time-scales relevant to climate. Their internal workings are based on statistical relations between economic variables devised for present-day conditions. There is no particular reason why these relations should be valid in the future when the characteristics of society will almost certainly have changed. As Michael Crichton put it: “Our [economic] models just carry the present into the future.” And as Kenneth Galbraith once remarked: “Economic forecasting was invented to make astrology look respectable.”
Discounting the future.
There is a lot of discussion among academics as to what should be an appropriate “discount for the future” to apply in the cost-benefit calculations associated with human-induced climate change. {Ed. note: see the activists’ explanation here.} The discussion quickly becomes incomprehensible to the average person when phrases such as “cross generational wealth transfer” and “intergenerational neutrality” and so on appear in the argument. These are fancy terms supposedly relevant to what is essentially a qualitative concept of fairness to future generations. The concept is so qualitative that there is virtually no hope of getting general agreement as to how much we should spend now so as not to upset the people of the future.
There are two extremes of thought on the matter. At one end there are those who tell us that the present-day view of a benefit for future generations should be discounted at the normal rate associated with business transactions of today. That is, it should be something of the order of 5% to 10% a year. The problem for the academics is that such a discount would ensure virtually no active concern for the welfare of people more than a generation or so ahead, and would effectively wipe out any reason for immediate action on climate. At the other end of the scale, there are those who tell us that the value of future climatic benefit should not be discounted at all – in which case there is an infinite time into the future that should concern us, and “being fair” to that extended future implies that we should not object to spending an unlimited amount of present-day money on the problem.
Academics tie themselves in knots to justify the need for immediate action on climate change. For example, we hear argument that “discounting should not be used for determining our ethical obligations to the future” but that (in the same breath) “we endorse a principle of intergenerational neutrality” – and then we hear guesses of appropriate discount rates of the order (say) of 1.5% a year.
Summary.
The significant point in this cost-benefit business is that there is virtually no certainty about any of the numbers that are used to calculate either the likely change of climate or the impact of that change on future populations. In essence it is simply assumed that all climate change is bad – that the current climate is the best of all possible climates. Furthermore, there is little or no recognition in most of the scenarios that mankind is very good at adapting to new circumstances. It is more than likely that, if indeed climate change is noticeably “bad”, the future population will adjust to the changed circumstances. If the change is “good”, the population will again adapt and become richer as a consequence.
If the change is a mixture of good and bad, the chances are that the adaptive processes will ensure a net improvement in wealth. This for a population which, if history is any guide, and for reasons entirely independent of climate change, will probably be a lot wealthier than we are. Perhaps the whole idea of being fair to the people of the future should be reversed. Perhaps they can easily afford to owe us something in retrospect.
The bottom line of politically correct thought on the matter – the thought that we must collectively do something drastic now to prevent climate change in the future – is so full of holes that it brings the overall sanity of mankind into question. For what it is worth, one possible theory is that mankind (or at least that fraction of it that has become both over-educated and more delicate as a result of a massive increase of its wealth in recent times) has managed to remove the beliefs of existing religions from its consideration – and now it misses them. As a replacement, it has manufactured a set of beliefs about climate change that can be used to guide and ultimately to control human behaviour. The beliefs are similar to those of the established religions in that they are more or less unprovable in any strict scientific sense.
—————————–
For more about the climate uncertainty monster
See “Climate Science and the Uncertainty Monster” by J. A. Curry and P. J. Webster in the Bulletin of the American Meteorology Society, December 2011.
Curry has written more about this at her website, Climate Etc.
- The Uncertainty Monster.
- Uncertainty about the Climate Uncertainty Monster.
- Climate uncertainty monster: What’s the worst case?
About the author
Garth Paltridge was a professor and director of the Institute of Antarctic and Southern Ocean Studies at the University of Tasmania from 1990 until his retirement in 2002, and is now an Emeritus Professor and Honorary Research Fellow. He is also a Visiting Fellow at the Australian National University. He made contributions over a wide range of atmospheric sciences including stratospheric electricity, the effect of atmosphere on plant growth and pioneering studies on the radiation properties of clouds. See Wikipedia.
Paltridge was a consultant at the World Meteorological Organisation in Geneva for the World Climate Research Programme (1975), He was a fellow of the Australian Academy of Science, and served on its Council from 1991 to 1994. He is the author of The Climate Caper: Facts and Fallacies of Global Warming
For More Information
Ideas! For some shopping ideas, see my recommended books and films at Amazon.
If you liked this post, like us on Facebook and follow us on Twitter. For more information see The keys to understanding climate change and these posts about climate propaganda. The good news is that the very bad news is wrong.
- A look at the workings of Climate Propaganda Inc.
- What you need to know about hurricanes and their trends.
- Wildfires and climate change: fake news in action.
- Scary but fake news about the National Climate Assessment.
- A new book with unexpected good news about polar bears – Refuting the doomster propaganda.
- New climate porn: it forces walruses to jump to their death!
- Weather porn about Texas, a lesson for Earth Day 2019.
- Terrifying predictions about the melting North Pole!
- The Extinction Rebellion’s hysteria vs. climate science.
Paltridge’s book
The Climate Caper: Facts and Fallacies of Global Warming
From the publisher …
“So you think the theory of disastrous climate change has been proven? You believe that scientists are united in their efforts to force the nations of the world to reduce their carbon emissions? You imagine perhaps that scientists are far too professional to overstate their case?
“Maybe we should all think again. In The Climate Caper, written with a light touch and presented in a nicely readable manner, Garth Paltridge shows that the case for action against climate change is not nearly so clear cut as is presented to politicians and the public. He leads us through the massive uncertainties that are inherently part of the “climate modeling process”; he examines the even greater uncertainties associated with economic forecasts of climatic doom; and he discusses in detail the conscious and subconscious forces operating to ensure that skepticism within the scientific community is kept from the public eye.
“Paltridge concludes that governments are indeed becoming captive to a scientific and technological elite―an elite that achieves its ends by manipulating the public through fear of climate change, creating the world’s greatest example of a “religion” for the politically correct.”
Quote from “Will climate change destroy democracy?” by Damon Linker in The Week.
The #ClimateEmergency hysteria is “creating a hunger for extra-democratic leadership to address the consequences with wisdom and resolution” – on the Left. Echoes of 1920s, when some Germans wanted a strong leader to solve their problems.
Even if climate change is real what do they expect us to do? No heat in the winter? Meatless Mondays? Replace cars with horses?
My opinion is all this climate change is just a tax grab.
Sven,
“Even if climate change is real …”
Of course climate change is read. It has made and destroy civilizations throughout history. Those that don’t adapt, are wrecked. Also, there is no room for doubt that we are affecting the climate – anthropogenic climate change. The question, as usual in science, is how much and how fast. In some scenarios, the effects are painful.
“No heat in the winter?”
There is no reasonable scenario in which that is necessary. But oru present response is quite mad. We’re not even prepared for the inevitable repeat of past extreme weather, let alone likely future changes. We’ll pay big for our folly.
I’m surprised by the strength of your conviction concerning anthropogenic climate change. Are you referring to local changes such as the climate around a reservoir or a city?
I think it’s notable that the presumed force for climate change is global warming, and yet that is rarely mentioned by alarmists, even while they continue to rail against ‘greenhouse gas’ emissions. What is the nature of the dreaded change? It seems to be anything that can raise anxiety in the susceptible: hot weather, bitter cold, flooding, drought, etc.
dwieland,
“I’m surprised by the strength of your conviction concerning anthropogenic climate change.”
Why?
“Are you referring to local changes such as the climate around a reservoir or a city?”
Global weather is the sum of all local weather. Individual areas are warming or cooling.
“I think it’s notable that the presumed force for climate change is global warming, and yet that is rarely mentioned by alarmists”
You must be kidding. They natter on incessantly about the 1.5°C red line, and extreme scenarios like “hothouse Earth” (look at the endless stream of hits for that on Google).
“What is the nature of the dreaded change?”
I suggest that you look at the Summary for Policymakers of the recent IPCC special report. It is explicit and detailed, and written for a general audience.
“It seems to be anything that can raise anxiety in the susceptible: hot weather, bitter cold, flooding, drought, etc.”
Don’t conflate the reports by climate scientists with the propaganda by activists.
Yeah, I know the 1.5 degree bit is frequently mentioned and I didn’t put it right. But I see statements of anxiety that seem to quaver at disembodied climate change that doesn’t relate to warming in any obvious way. As for global warming, satellite measurements aren’t showing anything significant, so what’s supposed to be driving climate change?
dwieland,
Satellite measurements are the least accurate of the three global measurement systems, as acknowledge by almost everybody in the fields (including two of the three primary research groups: RSS and NASA). The surface network shows warming. Ocean heat content is the most important, and shows steady warming (albeit the reliable record only goes back to ~2005, from memory).
See the RSS temp data.
Do you really believe that climate scientists are wrong about something so simple and basic?
dwieland,
I hit “send” too fast. Here is a 2014 quote from Carl Mears, senior research scientist at RSS. He has said this often.
Hmm. Your dismissal of the only global measurements surprises me. I certainly take anything from NASA GISS with a grain of salt, as Jim Hansen et al. have a vested interest in the AGW narrative. I thought you were well aware of how skewed climate science is. Even so, the actual warming reported by the IPCC isn’t alarming to a calm person. The ocean thing is heavy on conjecture, since the instrumental records are so sparse.
dwie,
“Your dismissal of the only global measurements surprises me.”
Please read more carefully. I cite and link to the work of RSS – one of the two satellite datasets.
” I certainly take anything from NASA GISS with a grain of salt”
Since you aren’t an expert in climate science, who cares?
Are you unaware that Jim Hansen is an alarmist? A Florida professor I communicated with regarding his presentation on ice ages sent me a link to an open peer-reviewed Hansen paper. That enabled me to see for myself not only Hansen’s advocacy style but also the numerous issues raised by reviewers, his dismissive response to several of them, and his media-savvy ‘pre-publication’ release to the media with a distinctly alarmist title. I’m in hospital at the moment, but I could send you the link when I’m home again.
May 7: “Global weather is the sum of all local weather. Individual areas are warming or cooling.”
Or showing no trend, as in most of Canada. (See, for example, weatherstats.ca for human readable data from Environment Canada.) But what leads you to attribute regional warming or cooling trends to humans?
May 7: “I think it’s notable that the presumed force for climate change is global warming, and yet that is rarely mentioned by alarmists, even while they continue to rail against ‘greenhouse gas’ emissions. What is the nature of the dreaded change? It seems to be anything that can raise anxiety in the susceptible: hot weather, bitter cold, flooding, drought, etc.”
I “typed” that on a phone while in the hospital and didn’t elaborate as I wished I had. This was soon after my city council (Ottawa, Canada) had caved to pressure from local activists and passed a “climate emergency” declaration. It made no mention of temperature, just “GHG emissions”. Considering that we were barely out of an extended winter, I guess I shouldn’t be surprised that global warming wasn’t featured as a concern. But what then could be the basis for this so-called emergency? That’s apparently a mystery not worthy of mention, as long as “the IPCC’s targets” can be a phrase in the declaration. I let my councillor, known as a conservative but who co-sponsored the motion, know that I found it embarrassing. (Apparently we do have two councillors clear-thinking enough to reject the declaration.)
May 7: “Satellite measurements are the least accurate of the three global measurement systems, as acknowledge by almost everybody in the fields (including two of the three primary research groups: RSS and NASA).”
The WaPo article you linked is disappointingly alarmist, even though it actually states the generally accepted ~1 degree Celsius rise over a century and a quarter (or so). The article’s link to information on NASA’s Aqua satellite is broken, but I found info on the NASA site. The WaPo article’s claim that it “carries an infrared device that is able to independently measure temperatures at the surface of Earth” doesn’t match what is on the NASA page (https://earthobservatory.nasa.gov/features/Aqua/Aqua2.php), but such is the state of science reporting in mass media. It does have a sounder from whose readings temperature can be calculated, as do the other satellites used for such measurement.
A good discussion of satellite temperature monitoring is at
http://www.drroyspencer.com/2019/04/uah-rss-noaa-uw-which-satellite-dataset-should-we-believe/.
I’d like to know what “as acknowledge by almost everybody in the fields” is based on.
Dwieland,
“I’d like to know what “as acknowledge by almost everybody in the fields” is based on.”
For starters, it’s based on what I’ve said it is based on.
You’re neither making any useful points, nor much sense. Thanks for commenting. Good-bye.
Bravo Dr. Paltridge!
“For what it is worth, one possible theory is that mankind (or at least that fraction of it that has become both over-educated and more delicate as a result of a massive increase of its wealth in recent times) has managed to remove the beliefs of existing religions from its consideration – and now it misses them. As a replacement, it has manufactured a set of beliefs about climate change that can be used to guide and ultimately to control human behaviour. The beliefs are similar to those of the established religions in that they are more or less unprovable in any strict scientific sense.”
Shouldn’t we be allowed expanding the above theory with:
“While the pivotal tenet of Abrahamic religions, that ‘Man was created in God’s image,’ gave birth and is nurturing the belief in Man Created Climate Change Catastrophe.”
I think we may all be sinful, yet we shall recognize that the sin of self-importance is the worst of them all…
As a follow-up to my “orphan” remark:
“…there is virtually no certainty about any of the numbers that are used to calculate either the likely change of climate or the impact of that change on future populations.”
Yet the IPCC AR-N’s always claim otherwise; why? — Do they have a vested interest in that business?
Assuming that “…current climate is the best of all possible climates.”
Perhaps the next IPCC meeting shall be held in the contrast of the usual locations they meet (IE Bali); hey, let’s make the next meet in mid-February of 2020 in Saskatoon, SK, Canada. The members should be issued a safety warning that even crossing the parking lot from the hotel to the venue location, one should wear parka, gloves and goggles!
“Perhaps the whole idea of being fair to the people of the future should be reversed. Perhaps they can easily afford to owe us something in retrospect.”
Absolutely! They shall honor us as we do honor our fore-bearers: with removal of their statutes and erasing their thoughts from our elementary school books.
Jako,
“Yet the IPCC AR-N’s always claim otherwise; why? — Do they have a vested interest in that business?”
Most of your comments about climate are fiction. This one is especially false. Try reading something other than right-wing propaganda. If you want to learn something, read the Summary for Policymakers from the IPCC’s AR5. It would dispel your ignorance like the dawn does the night.
Jako,
Just to be clear, let’s replay the tape.
Post: “…there is virtually no certainty about any of the numbers that are used to calculate either the likely change of climate or the impact of that change on future populations.”
Your comment: “Yet the IPCC AR-N’s always claim otherwise”
That is bizarrely false. Almost every finding and conclusion in the IPCC’s assessment reports is expressed with a certainty level.
“I may have read that pamphlet before you did …”
AR5 WGI is 1552 pages. It is not a “pamphlet” – definition: “a small booklet or leaflet” (add in WGII and WGIII and it is encyclopedia-length). That, plus your false statement above above confidence levels, suggest that you are either lying about reading it or have a very poor memory. That is, neither are likely statements from somebody who even briefly looked at AR5.
Also, a trivia point: I read the AR5 WGI draft when it was leaked (and got bootleg drafts of the SPM and some chapters even earlier). How did you read it before that?
Combine this with an ArkFlood Larry. Weeee!
Bryce,
That’s one of the worst scenarios for the Central valley! See my post about it: California’s past megafloods – and the coming ARkStorm, 14 February 2017.
As I have often said, while we bicker about the future – we do not prepare for the inevitable repeat of past weather.
Pingback: Enlisting peer-reviewed science in the climate crusade | Watts Up With That?