by Judith Curry
Growing realization by the climate establishment that the threat of future warming has been cut in half over the past 5 years.
Summary: The climate “catastrophe” isn’t what it used to be. Circa 2013 with publication of the IPCC AR5 Report, RCP8.5 was regarded as the business-as-usual emissions scenario, with expected warming of 4 to 5 oC by 2100. Now there is growing acceptance that RCP8.5 is implausible, and RCP4.5 is arguably the current business-as-usual emissions scenario. Only a few years ago, an emissions trajectory that followed RCP4.5 with 2 to 3 oC warming was regarded as climate policy success. As limiting warming to 2 oC seems to be in reach (now deemed to be the “threshold of catastrophe”),[i] the goal posts were moved in 2018 to reduce the warming target to 1.5 oC. Climate catastrophe rhetoric now seems linked to extreme weather events, most of which are difficult to identify any role for human-caused climate change in increasing either their intensity or frequency.
The main stream media is currently awash with articles from prominent journalists on how the global warming threat less than we thought. Here are some prominent articles:
- NYTimes David Wallace-Wells: Beyond catastrophe: A new climate reality is coming into view.
- WSJ: Good climate change news is fit to print. Slowly its percolating into the journalistic mind that recent research is upbeat
- NYT Bret Stephens: Yes Greenland’s melting but . . .
David Wallace-Wells is one of the most interesting journalists writing in the climate space. In 2017, he wrote a 2017 New York Magazine article titled “The Uninhabitable Earth”, with subtitle: “Famine, economic collapse, a sun that cooks us: What climate change could wreak—sooner than you think.” Not long after publication of his book in 2019 entitled The Uninhabitable Earth, David Wallace-Wells made this statement: “Anyone, including me, who has built their understanding on what level of warming is likely this century on that RCP8.5 scenario should probably revise that understanding in a less alarmist direction.” DWW scores HUGE number of points with me for quickly adjusting his priors with the growing amount evidence that RCP8.5 is implausible.
Well, the “messaging” around DWW’s latest article is that we are succeeding with reducing emissions (no we are not). The second message is to acknowledge that that warming will be less than we thought, but the impacts of the warming will be worse than we thought (nope). The third message is that advances in science have brought us to this (relatively) happy place (nope)
At the heart of this good news is abandonment of RCP8.5 from UNFCCC policy making. The hero of science behind this abandonment is Justin Ritchie, a recent Ph.D. graduate (whose work has been cited in previous RCP8.5 posts at Climate Etc).
The COP26 and now the COP27 have quietly dropped RCP8.5 (and SSP5-8.5) from their considerations, focusing on the envelope between RCP4.5 and RCP2.6. The grand poohbahs of the IPCC apparently didn’t see this coming (or preferred to keep spinning the alarm), since they instructed climate modelers for CMIP6 to continue a focus on SSP5-8.5, and climate researchers continue to focus on this scenario in their impacts publications. The IPCC AR6 prominently featured SSP5-8.5, although WGI did make this lukewarm statement
“In the scenario literature, the plausibility of the high emissions levels underlying scenarios such as RCP8.5 or SSP5–8.5 has been debated in light of recent developments in the energy sector.”
The second so-called scientific advance is lower values of climate sensitivity. The so-called advance is associated with the IPCC AR6 decision NOT to include values derived from climate models (which have dominated previous IPCC reports). They implicitly acknowledge that climate models are running too hot and that you can pretty much get whatever value of climate sensitivity that you want from a climate model (this has been blindingly obvious to me and many others for over a decade). The IPCC AR6 lowered the upper likely bound of ECS to 4.0oC (from 4.5oC previously); this further acts to reduce the amount of projected warming. The IPCC AR6 also raised the lower likely bound of ECS to 2.5oC (from 1.5oC). Raising the lower bound of ECS is on very shaky ground, as per the recent publication by Nic Lewis
The COP27 is working from a value of expected warming of 2.5oC by 2100. This is arguably still too high for several reasons. IPCC expert judgment dismissed values of climate sensitivity that are on the lower end (that should not have been dismissed as per Nic Lewis’ paper). Further, the IPCC projections do not adequately account for scenarios of future natural climate variability. See these recent posts:
X https://judithcurry.com/2022/01/23/crossing-or-not-the-1-5-and-2-0oc-thresholds/
X https://judithcurry.com/2021/11/21/solar-variations-controversy/
In addition to an insufficient number of solar and volcanic scenarios, the climate models ignore most solar indirect effects, and the climate model treatment of multidecadal and longer internal variability associated with ocean circulations are inadequate. While in principle these factors could go either way in terms of warmer vs cooler, there are several reasons to think these natural factors are skewed towards cooler during the remainder of the 21st century:
- Baseline volcanic activity since 1850 has been unusually low
- Most solar researchers expect some sort of solar minimum in the mid to late 21st century
- Solar indirect effects are inadequately treated by climate models, which would act to amplify solar cooling
- A shift to the cold phase of the Atlantic Multidecadal Oscillation is expected in the next decade, which influences not only global temperatures but also Greenland mass balance and Arctic sea ice.
Once you include alternative scenarios of natural variability, temperature change by 2100 could easily be below 2oC and even 1.5oC. Recall that this warming is with reference to a baseline of 1850-1900; 1.1oC warming has already occurred.
Impacts
David Wallace-Wells provides some “hope” for the climate alarmists with this sentence:
“It’s sadly apparent by now that scientists have underestimated, not overestimated, the impact of warming.”
I just don’t know what further to say here. The IPCC AR6 provides very meager fodder to support DWW’s statement. Apart from sea level rise, which is unambiguously associated with global warming, there is no prima facie reason that extreme weather events would worsen in a warming climate. Observational evidence, provided that you go back at least to 1900, shows that nearly all horrible, recent weather and climate disasters have precedents in the 20th century and hence “detection” is very challenging. Climate models are not fit-for-purpose to simulate extreme weather events, let alone to attribute them to human caused warming. We are then left with back-of-the-envelope simple thermodynamic calculations to infer worsening of extreme weather events, which ignores the overwhelmingly dominant role of atmospheric and oceanic circulations.
Think about the implications of assuming extreme weather and horrible impacts are highly sensitive to a 0.5oC temperature change. If so, this leads to the conclusion that the dominant climate factor is natural climate variability, with year-to-year swings of several tenths of a degree from El Nino and La Nina, a substantial volcanic eruption, and/or multidecadal ocean oscillations. The rationale for ignoring natural climate variability is based on the assumption that large amounts of fossil-fueled warming from climate model simulations spiked by RCP8.5 and high values of ECS will swamp natural climate variability. Cut the warming in half (or reduce even further), and you lose the rationale for ignoring natural climate variability.
So is all this a “victory” for climate science? I don’t think so. But I told you so . . .
And finally Bret Stephen’s article includes this all important figure. Are we to infer that warming causes fewer deaths (well there is a STRIKING correlation)? Well maybe, but the real cause of this decline is increasing wealth, increased warnings, and adaptation to weather and climate extremes.
Extreme weather and climate events are something that needs to be dealt with independently of the AGW issue. The world has always suffered from weather and climate extremes, and it always will; this will not change with further warming or with emissions reductions.
COP27
The policy implications of all this is enormous. Unfortunately I suspect that the COP27 will focus too much on emissions reductions (which aren’t working and wont impact the climate in any event), and not enough on supporting development and adaptation for developing countries and most importantly supporting development in Africa by allowing them to benefit from their fossil fuels (other than by selling them to Europe). With regards to the later, a shout out to Rose Mustiso’s recent Nature publication; Rose is my favorite African activist and thinker on this topic.
Nicely put as Richard Lindzen wrote in 2009: “… there are the numerous well meaning individuals who have allowed propagandists to convince them that in accepting the alarmist view of anthropogenic climate change, they are displaying intelligence and virtue For them, their psychic welfare is at stake”.
You are right there Chris .
I just heard a Australian commentator who is given a slot on our mid day country session in New Zealand .
The radio station had recorded what he said last week and he was going off the deep end.
He was in a real panic about his imagined threat of the upcoming climate crisis.
According to his rant everything about the climate was getting worse and will get worse in the future.
Floods ,droughts and everything in between is caused by that demon CO2 was his message.
A warmer atmosphere will hold more water vapour but how does that cause more droughts ?
I would like to see climate scientists stand up and tell the world that the band widths in the atmosphere are saturated with CO2 and very little if any more warming will occur due to rising emissions .
This has been known for over 100 years but is suppressed as are many other facts concerning emission profiles and how individual countries emissions are assessed when they are exporting large amounts of food.
Declining deaths due to increasing wealth is about to be reversed as the developed world commits economic suicide in part due to insane energy & climate policy.
That’s not a joke – watch Europe this winter with their lack of energy to keep their citizens warm
Could rationality on this topic be breaking through?
Be still my bleating tart!
(she doesn’t always do what I tell her to 🙁 )
Could rationality on this topic be breaking through?
I’m sure they’ll fix that ASAP.
You know the wheels are coming off the climate bus when Greta Thunberg doesn’t go to COP27 because it’s just ‘green washing’, then calls for the end of capitalism instead.
When even the NYT is waking up, the end of alarmism must be nigh:
So Greta calls for the end of capitalism. Wasn’t that the end game always?
Yes, the “climate catastrophe” and the “end of the world as we know it” — is caused by industry, consumers, and all capitalist running dog nations.
its Gretta’s leftist lunatic father speaking again
She hasnt got the IQ to put two words together
Also when she was at these events previously she was proven illiterate and always pushed the question to someone else
No loss the sooner she is last years news the better
Always bad news, it just seems to come every day. I’m in the Cariboo of central BC, just getting ready to bundle up and go to the ranch next door with my tractor to haul water to their corral of steers again–the automatic waterer froze up night before last–at -8C and anticipating 20 cm of snow in a 40 km/hr wind starting any time now. And now you tell me that it won’t even be up to -6C in a 40 km/hr wind when I have to do the same thing in 2100?
Well, crap. I really was hoping for something better.
And your fellow Canadians are hopelessly brainwashed. The obvious self interest in a hypothetical few degrees of beneficial warming has been replaced by ignorance. I recently asked some snow birds to explain why they would be concerned with warming. Melting permafrost and polar bears was the answer.
Aw, those must be draft dodgers who immigrated to Canada during the Viet Nam war.
Your point is well taken; we do have the gullible here too. They self identify by their cognitive dissonance of escaping Canada to somewhere warmer every winter despite their belief that the world–everywhere else from anything they’ve personally experienced of course–is getting too hot.
And then they burn fossil fuels to get there, and to get back again in the spring–which they do only to avoid the tax consequences of staying more than 6 months. Always someone else needs to DO something–like I should have carried that water by hand instead of using my 4WD Kubota an hour ago, stated with feigned sincerity while sipping a margarita under a palm tree in a retirement trailer park in Palm Springs. Like, I should pay more taxes on the diesel the Kubota burned while they avoid all the taxes they can.
Check out Quick Dick McQuick sometime; he’s the quintessential Canadian. I could have made a similar video in the snowstorm ridiculing Global Warming just this afternoon.
In fact, send any of those Sham-el-Sheep attendees out here instead of going to Egypt, the boys next door were out on the range on horseback today rounding up the last of the herd in this blizzard, we’ll send those suits out there to help them. I’ll bet good money they’ll come back with a far different view of ‘climate’ than they present at cushy catered symposia.
Send Mikey; I’d love to see him out there. If he stays long enough he just might learn what a real hockey stick is.
AND–should Mikey ever get a real hockey stick in his hands up here, he’d have to help shovel off a rectangle of Beaverdam Lake to use it. Should an over-zealous slap-shot bury the puck into the snowbank around the edge of the rink, by the time he digs it out with bare hands he’ll have a much better understanding of the black-and-white of climate than he’s ever gained sitting at a computer in a university office in Philadelphia.
The tax on distilled beverages is very high, no matter where one sips it.
“Aw, those must be draft dodgers who immigrated to Canada during the Viet Nam war.”
They were life long Canadian natives. I suspect trapped in an echo chamber bubble of media propaganda their fellow citizens blindly accepted. They couldn’t believe that polar bear populations are healthy because of their programming.
your prime minister banning nitrogenous fertilizer will not help the future food supply to canadians
Well, if ‘The Climate Crisis’ isn’t such an unprecedented critical crisis any more, what can the population worry about now ???
On a personal note, I shall go back to worrying that the tooth fairy will come & steal my dentures.
Plus ça change, plus c’est la même chose. Thank you for the post. Please help me understand one thing. RCP, as I understand it, is a forecast for greenhouse gas emissions, which in turn can be used as input to climate models to predict warming. When you say there is recognition that RCP8.5 is off, isn’t it really the models that are off? Aren’t actual GHG emissions following, more or less, the RCP8.5 track?
No. If you read Judith’s post closely, BAU is about RCP4.5, NOT the near impossible 8.5. That gives the BAU (do nothing) emissions baseline fed into the IPCC climate models—which under any emissions scenario run way too hot.
Put differently, the model inputs are off. The outputs are more off.
Rud, the whole RCP business seems so cloudy and dishonest to me. It is very hard to wrap my brain around it. I found this at Climate Nexus:
“RCP 8.5 is one of a suite of scenarios (Representative Concentration Pathways) that describe several potential future pathways. Each scenario defines a pathway in terms of the concentration of carbon in the atmosphere at any date – note that these pathways are defined in terms of the concentration (i.e. the level) of carbon in the atmosphere, not the volume of carbon emissions. RCP 8.5 refers to the concentration of carbon that delivers global warming at an average of 8.5 watts per square meter across the planet. The RCP 8.5 pathway delivers a temperature increase of about 4.3˚C by 2100, relative to pre-industrial temperatures. RCP 8.5 is often contrasted with RCP 2.6, which would deliver a total warming of about 1.8˚C by 2100. The researchers who developed the RCP 8.5 scenario describe the pathway in detail here.”
So they label the different pathways by how much that pathway will increase total global warming measured in watts per meter squared. Do I have that right? Assuming I do that would tell me that they know what total CO2 concentration it would take to increase warming by a specific number of watts per meter squared. Do I have that right? They also state that the RCP 8.5 pathway would increase global temperatures by 4.3 degrees C by 2100. They don’t say what concentration of CO2 results in an additional 8.5 watts per meter squared but for my argument let’s say it is 600 ppm. Why wouldn’t they label the RCP as 600 ppm or 4.3 C increase. Everyone could understand that and relate to that easily.
They are dishonest bottom feeders.
They don’t want average people or journalists (and how many journalists reach ‘average’?) to actually understand what the different scenarios represent. That’s why they call 8.5 ‘business as usual’ instead of stating what it actually represents.
If anyone demonstrates that the real probability is that we would not likely see anything more than 1.5C by 2100, unless the fantasised feedbacks and ‘tipping points’ exist, which they patiently do not, they are shut down immediately.
8.5 is now ‘gospel’. I’m glad that at least 4.5 is being considered. I’ll be happier when 1.5 is discovered to be the most likely. Then we’ll be able to concentrate on real problems like energy security, food security and inflation.
The real problems are those being created by their climate POLICIES, which will do, and in fact have already (to the small extent put in place) done, a great deal more damage to human existence than their hypothetical, speculative, and ultimately non-existent “effects” of CO2 increases will ever do.
The only actual, as opposed to hypothetical, “crisis” is what will result if the Eco-Nazis get their way and implement their mind-numbingly stupid policies.
The use of the term “pathway” indicates an ignorant person/s who has/have recently attended a seminar and returned a zealot
It’s more worser than that, NOAA faked the data to show the “pause” never happened:
https://electroverse.co/climate-scientist-who-exposed-noaa/
As I understand it that’s a federal crime.
I’ve never seen or read what I would call a quantitative comparison of the various emissions scenarios. Since what’s been done up until now does not seem to have affected GHG emissions much (the Keeling curve is not bending), we would seem to be following the 8.5 (BAU) track. However, there hasn’t been much time elapsed so the differences in terms of, say, CO2 concentration in the present is probably not much different for any of the scenarios. I’d like to see the scenarios presented as a simple forecast of atmospheric CO2 concentration. I assume this exists somewhere.
Two important points, one missed:
Why ECS and RCP 8.5?
To scare people, that’s why.
The IPCC also has a guess for the global average temperature in 70 years called TCS. Run models for 70 years TCS with RCP 4.5, and the result is similar to observations since 1975 (1975 to 2022 is a cherry picked period to emphasize global warming, with bureaucrats usually using the worst case assumption that all warming since 1975 was manmade, which is unlikely).
Run the models for ECS (several centuries) with the worst case unrealistic RCP 8.5 and you get scary predictions. That’s what the iPCC wants, and that’s what the IPCC shows you. Almost everyone assumes the IPCC (ECS) prediction is for 50 to 100 years, when it i really a wild guess for several centuries from now!
The IPCC has 34 years of over=predicting global warming, except the Russian INM model that gets no special attention. In plain English, the climate confusers are programmed for the scary predictions that the “management” (governments) want.
There is no intention of making accurate predictions, and no reward for doing so. Of course computers predict whatever they are programmed to predict.
The average climate computer game prediction represents the mainstream climate consensus. The climate consensus came first, in the 1970s, and the computer games were then programmed to generate the same (wrong) predictions.
There is only one climate prediction in the world that has been correct for a 25 year period — my own 1997 prediction — made after intense study of climate science, for about one hour: “The climate will get warmer, unless it gets colder.”
We can assume a worst case — that CO2 caused all the climate change since 1940. Here’s what happened in the past 82 years:
1940 to 1975 — global cooling trend, no warming
1975 to 2016 — global warming trend
2016 to 2022 — flat trend, no warming
NOTE: IPCC guesses using RCP 8.5 CO2 scenarios:
In several centuries (ECS in AR6): +2.5 to +4.0 degree C.
In 50 to 100 years (TCS in AR6): +1.4 to +2.2 degree C.
Richard, you missed the pause, hiatus or whatever anyone wants to call the period between 1997 and 2014-15 that had about an 18+year stretch of minimal upward temperature trend. The period of quiescence was particularly notable because the UN IPCC CliSciFi climate models have trends much above observed trends over the period.
The land surface temperature estimates are hopelessly UHI corrupted. Radiosondes and UAH6 deep-atmosphere temperature estimates are a much better gauge of temperature trends, as is ARGO for ocean temperatures since about 2004. The atmosphere, where the GHE occurs, has a warming trend of only about 0.13 ℃/decade according to UAH6. And that minor warming occurred during a rising portion of the of the approximately 70-year cyclic fluctuation up and down warming and cooling. Additionally, no model-predicted atmospheric Hot Spot has been measured.
short tern data mining using a huge 1998 el nino neat release to bis the trend line.
The models are intended to scare people. You seem to think they are intended to make accurate predictions — after 40 yeas of inaccurate predictions, accuracy is obviously not a goal. So reality and model predictions will NEVEF match, because climate reality is mild harmless global warming, with many short term apuses in the records. Climate reality doesn’t scare people.
The current International Mining Conference in Sydney has come out in strong support of the global warming narrative and the need for humungous increase in mining. The figure being thrown around is a 4-fold increase in mined volume to meet the projected demand of the stuff needed to start the journey to NutZero.
That single reality means it can never happen. The expansion of mining by that factor in a lifetime is IMPOSSIBLE. And doubtful on any time scale.
Hah–the classic Baptists and Bootleggers scenario. Being a former mine geologist I can only applaud; they might as well take advantage of the stupidity, you can’t cure it.
And the fact that it is not only futile (since the key players in rising emissions are not on board, since the emissions don’t actually drive the climate anyway, etc.) but will do far more environmental damage than the mythical effects of CO2 are conveniently overlooked, of course.
Thank you, Judith, for preparing this post, and thank you, WUWT, for cross posting it here.
Regards,
Bob Tisdale
That ENSO Guy? Is being a WUWT Editor going to your head, Bob? 😁
The Nature article is weird, talks about modeling African decarbonisation! What Africa needs right now is massive exploitation of coal, oil and gas. Get on with it. Ignore the silly greenies, they will kill you.
They are getting on with it, because Europe needs their gas.
https://www.cfact.org/2022/11/02/un-cop27-its-a-gas-gas-gas/
Unfortunately a majority of the population still believes the climate crisis lie. It’s beyond their comprehension that reality could be so different than their programming.
Mathematics and critical thinking are severely discouraged in the majority of U.S. public “schools”. Why, students who think for themselves must be racissts!
Here in the US polls suggest that only about half even accept AGW, so those buying the crisis should be significantly less. Unfortunately a relatively small fraction of devout fanatics can dominate the political narrative. This is what we are seeing. The good news is such narratives can cease to be influential fairly quickly.
AGW is real, so only half of Americans believing AGW (which I believe is NOT a correct number — prove it) would be shocking.
Media propaganda has convinced the ignorant that AGW=catastrophic warming. The modest human forcing accepted by almost everyone is not part of the consideration.
Adherence to the Gospel of CAGW is a mile wide and an inch deep. Joe Q Public will change his mind the second he gets his gas or electricity bill, or when he fills up his car.
I hope you are correct!
Such is the sad state of climate science, where journalist interpretation has a greater influence than scientific rigor. Where the fight is in the press, rather than in the literature and academic institutions. A battle of perception, not one of objective reality.
A fate attached upon any science that exists at the interface with policy.
Eisenhower was a prophet, he saw it coming before I was born…
How’s about we declare victory, pull the rug out from under them?
And once you drop your guard BOOM! Right hook in your gut.
RCP8.5 scenario was NEVER reasonable or remotely defensible.
RCP4.5 is barely defensible and is unreasonable.
There was never been any actual data linking CO2 Emissions to any worsening weather trends.
The unnecessary pain and death and destruction coming this Winter… and even worse next Winter… should shift popular opinion strongly against spending $50 Trillion (US only) for a non-existent problem.
The Fake Climate Crisis is an engineered weapon designed by the Unelected Globalist Elite to help them consolidate more illegitimate power. (They control the Press, Academia, the Deep State, and the Democrat Party.)
Hopefully, they have overstepped the tolerance of the people this year, and will be exposed and rebuked.
Two things that go together:
1 – Per the above article, the realization that the potential for global warming is less than half of what some folks supposed it was.
2 – An energy crisis brought about by “de-carbonization”.
This may be an opportunity for some politicians to stiffen their spines and call out the green madness for what it is. Otherwise, grandma’s going to freeze in the dark.
Warming has not really been “global” since the 1970s:
Mainly affecting the upper half of the Northern Hemisphere, mainly in the coldest six months of the year and mainly at night (TMIN)
Agree Richard. If you look at the data, most of the late 20th C warming was in the Arctic due to influx of warm equatorial waters which melted the sea ice and allowed energy to be radiated to space through the atmosphere thus warming it . This is an entirely natural as is the boost in World average temperatures due to cyclical El Niño events.
These two phenomona are entirely local events and actually are examples of the loss of heat from the oceans I.e a reduction in total earth enthalpy?(Earth actually cooling!!)
They also demonstrate the dominating effect of sea surface temps on climate
So slight increase in average lower atmospheric temperatures is somewhat meaningless as the metric is dominated by regional effects.
Although the average warming is significant, the warming is not Global
Which makes it benign, even beneficial.
In the great words of Emily Litella: “Never mind.”
“The hero of science behind this abandonment is Justin Ritchie, a recent Ph.D. graduate (whose work has been cited in previous RCP8.5 posts at Climate Etc).”
I pose the following question. If a billionaire Canadian communist highschool dropout created The 1972 United Nations Conference on the Environment in Stockholm (which was the first world conference to make the environment a major issue), then in 1988 cobbled together the UN IPCC, charging them with “advancing knowledge on human-induced climate change” then in 1992 created The United Nations Rio de Janeiro Earth Summit, ‘the Rio Summit’ (checkout Wiki and scroll to the issues discussed), and next, created the UN Framework Convention on Climate Change in 1994, that “commits state parties to reduce greenhouse gas emissions, based on the scientific consensus that global warming is occurring and that human-made CO₂ emissions are driving it”(!!), what possessed anyone calling themselves a scientist to buy into this richly flagged and repeatedly advertised scam?
From the beginning, they didn’t even have a ‘man behind the curtain’. He was in plain view. Even Christiana Figueres, former Secretary of the UNFCCC, didn’t seem to believe there a was climate worry. She felt even if Antho Crisis Global Warming was B.S . redistribution of wealth was a good enough rationale for the plan. And the commie dropout? Even before Michael Mann, Richard Betts, Stefan Ramsdorf the rat’s nest of U of East Anglia, GISS, The Poison Ivy League … Maurice Strong informs us that ” Isn’t the only hope for the planet that the industrialized civilizations collapse? Isn’t it our responsibility to bring that about? ”
Man alive! And you all jumped in to bring this about. You have been phoned by a highschool dropout.
With a likely change in Twitter policies toward climate this may be people trying to reset their positions with far more skeptical tweets headed their way.
It certainly looks like there is some backing away by certain members of the Climate Establishment although this is yet to be reflected by the commentariat.
Recent admissions by the scientific “establishment” that the models are running too hot are stating ,belatedly, the ’bleeding obvious”. Roy Spencers recent post demonstrates this unambiguously showing that ALL of the models run hot, based on the actual data.
The interesting outcome from this seems to be a deafening silence from the Climate modeling community, despite the absolutely inherent massive implications.
Why are models running hot is surely the trillion dollar question as it goes to the heart of Climate Science as we know and understand it.
The deduction I would make is that, because all models run hot there are probably common basic assumptions use by all modellers that are wrong.
It is obviously not a “tweaking “problem.
Two logical possibilites
For example perhaps the accepted World average temperature at the start of the industrial revolution was much warmer than that assumed? (distinct lack of thermometers everywhere and almost totally absent in the Southern Hemisphere) To claim to know this value with an accuracy of a tenth of a degree is a bit hubristic IMHO.
A higher historical temperature would reduce deduced climate sensitivity.
Also the assumption that elevated CO2 actually results in retention of heat in lower atmospheric , which is basic to the whole science. Although apparently soundly based in science , this lacks empirical evidence to support it. (High quality data from Central Australia shows no increase in minimum temperatures and no reduction in Tmax-Tmin since post war period) (ref BOM Giles WS)
Climate modelers are thus between a rock and a “very hard’ place as adjusting their model outputs to reflect reality they might have to knock out some of their support assumptions, and in doing so they may just remove their reason for being.
Perhaps that explains their silence.
If the models are running too hot…..WHY?
“If the models are running too hot…..WHY?”
Their premise is that CO2 is the control knob of climate. All conclusions that follow this false assumption are invalid. They attributed too much historical warming to CO2 so the models are tuned hot.
I wonder what the extreme left will move onto next?
Falling rates of O2 due to man-made CO2?
/sarc if needed
I hope Griff reads this and starts to think for himself
OK, the first part of my comment I’m sure about. The second part, not so much
“Climate models are not fit-for-purpose to simulate extreme weather events, let alone to attribute them to human caused warming.”
This is important. It seems every adverse weather event is being attributed to “climate change” based on the misuse of the models. It’s bad enough that the models have no diagnostic or predictive authority to simulate what emissions of non-condensing greenhouse gases will do to the disposition of absorbed solar energy over the long term. But this new “attribution science” misuse of the models takes nonsense to a whole new level.
“The grand poohbahs of the IPCC apparently didn’t see this coming (or preferred to keep spinning the alarm), since they instructed climate modelers for CMIP6 to continue a focus on SSP5-8.5, and climate researchers continue to focus on this scenario in their impacts publications.”
Then it isn’t science, but politics. Science seeks truth. Politics seeks talking points. Prove me wrong.
With reference to the “summary” (top) paragraph, it appears the conventional wisdom is that the less we have to fear from a changing climate, the more stringent the restrictions on our behavior need to be. Is it unreasonable to conclude, therefore, that climate conditions are not the primary motivating interest?
Your second option is correct.
The WG-I reports, AKA “The Physical Science Basis”, are probably the ones most WUWT readers (including myself) have focused on.
While the AR6 WG-I report admits … in the main report, not in the SPM … that both SSP3-7.0 and SSP5-8.5 (which neatly bracket RCP8.5) are “counterfactuals”, and that “the medium RCP4.5, RCP6.0 and SSP2-4.5 scenarios” should be considered as worst-case scenarios … ones with “the absence of additional climate policies” … there are two other Working Groups staffed by “the grand poohbahs of the IPCC”.
The AR6 WG-II, “Impacts, Adaptation and Vulnerability”, report has a “Cross-Chapter Box CLIMATE” with a sub-section titled “AR6 WGI Reference Periods, Climate Projections and Global Warming Levels” (on page 1-22) :
– – – – –
The WG-III, “Mitigation of Climate Change”, authors were confident enough to promote these speculative ideas to the SPM for AR6 (paragraph C.1.3, page SPM-22) :
What’s in Box 3.3, “The likelihood of high-end emission scenarios”, you may well ask ?
Jumping to page 3-28 (of WG-III) we find :
Even with the admission that SSP5-8.5 / RCP8.5 is not BaU, “the grand poohbahs of the IPCC” haven’t given up a damn thing when it comes to frightening people with “catastrophic” model projections.
It would be very interesting to see a chart of IPCC climate temp predictions from start to projected 2100. It should be showing a dramatic decline ?.
FAR numbers from SPM Figure 8, “Temperature Extreme Values”.
SAR (IS92) numbers from Figure 6.24, “Temperature Extreme Values”.
TAR (SRES) numbers from Appendix II, Table II.4.
NB : “Ensemble mean / 50%” values rather than “extremes”, hence the narrower range.
AR4 (SRES) numbers from Figure 10.26.
NB : “Min” values selected from the “-1 sigma” set, “Max” values from the “+1 sigma” set.
AR5 (CMIP5 / RCP) numbers from Appendix II, Table II.7.5.
NB : “Min” values selected from the “5%” columns, “Max” values from “95%”.
The AR6 (CMIP6 / SSP) projections I have found so far have all been “ensemble mean / 50%” data series, and are therefore not directly comparable (except with the TAR).
There is something annoying about this article. People are being feted for coming to a belated realization that the technical data don’t support a true crisis, never has, something any number of people here have known for a long time, and have even been stating publically in any number of venues; but they still cannot bring themselves to recognize the more important truth that the proposed solution to the crisis is far worse than the crisis, itself, and is all but impossible to achieve. To fully commit a nation to it is ruinous.
I suspect there might be soon a tsunami of rationality released once the guilty parties figure out a way to reverse course without saying “What were we thinking? We were wrong.”
I respect Curry’s work but disagree. Based on measurements of global average temperature and both tide gauge and satellite measurements of average sea level trends, RCP2.6 is the “business as usual” scenario.
The RCP4.5 scenario predicts a temperature increase mean by 2100 of 1.8 °C (likely range of 1.1 to 2.6}. RCP2.6 predicts 1.0 (range of 0.3 to 1.7).
The UAH temperature trend measured since 1979 is 1.3 °C per century, well within the range of RCP2.6 and closer to its mean of 1.0 than the RCP4.5 mean of 1.8.
RCP4.5 predicts a sea level increase mean of 0.47 meters (likely range of 0.32 to 0.63). RCP2.6 predicts 0.4 meters (range of 0.26 to 0.55).
The satellite-measured sea level rise trend since 1993 is 3.3 (± 0.4) mm/yr, or 0.33 meters by 2100, barely in the lower end of the range of RCP2.6 and below its mean of 0.4 meters.
QED
As you indicate the observed physical data in conjunction with IPCC modeling all points towards the absolute min of projections which in turn would be within natural variability and definitely no climate crisis.
The RCP 8.5 scenario is impossible because there is not enough coal, oil and gas to make it happen based upon current reserves. It is not that hard to work out.
Add in the fact that the oceans are a huge CO2 absorber that will probably absorb all that CO2 over a few hundred years anyway and form a ocean-atmosphere balance at a much lower level than the peak.