There’s been a rather contentious Twitter thread about RCP8.5, a concentration/forcing pathway I’ve discussed before. It started with a claim that it was “bollox” followed by a suggestion that it was mainly used for generating headlines, scaring gullible folk and children, and giving climate contrarians a reason to ignore the need for urgent action on emission mitigation.
A number of us pointed out that there were still valid reasons for using an RCP8.5 concentration/forcing pathway and that suggesting that it was mainly used for generating headlines and scaring gullible people was just promoting a denialist conspiracy theory. Fortunately, some other sensible people also chipped in and pointed out that we probably couldn’t yet rule out an RCP8.5 concentration pathway, that it was still useful for inter-model comparison, and that it was a useful pathway for impact studies because of the large signal to noise. None of this means that there aren’t some valid criticisms, but claiming it’s “bollox” and simply used to scare gullible people is just nonsense.
What I found frustrating is that I think this is an interesting/important issue and it would be worthwhile to be able to discuss it sensibly. However, I particularly dislike suggestions that the reason we haven’t effectively implemented climate policy is because of the behaviour of climate scientists, and so I failed to hide my frustration as well as I probably should have. I did learn some things from some of the comments, but the overall discussion was unfortunate and I think it ultimately created some artificial divisions between people who probably mostly agree.
Unfortunately, I think this is becoming all too common. My impression is that we’re now in a position where people who probably mostly agree about the issues, are in conflict over details that probably don’t really matter. Fundamentally, whether we use RCP8.5 in climate models, or not, the basic message is the same; we need to start reducing emissions soon. It’s possible that some contrarians will use that climate scientists use RCP8.5 to argue that they’re intentionally exaggerating the risks. However, if climate scientists stopped using RCP8.5 the same people would simply find something else to criticise. The idea that scientists should stop doing something in order to counter those who are clearly engaging in bad faith doesn’t make any sense to me.
I really do wish it were possible to have these nuanced discussions without it turning contentious; that it were possible to have a discussion where maybe people didn’t end up agreeing, but still learned something. Probably human nature that it’s the exception rather than the rule, but it’s still unfortunate. Does make me wonder if we’ll ever really get into a position where we can implement any kind of effective climate policy. Hopefully, we’ll either overcome this, or that what we do end up managing to do is enough to avoid the more serious consequences.
...and Then There's Physics 
Understanding RCP 8.5 demands understanding that the biggest uncertainty in climate projections comes from substantial inability to know which emissions path humanity will track and the role of-end-members.
That said, the effectiveness of luckwarmer or denialist arguments is a testament to the fact that most. U.S. and perhaps most OECD residents would much rather prefer that climate sensitivity to CO2 not be what it is, and that other explanations would be found for increasingly extraordinary events. They do not want to change their lifestyles or jobs or habits. They do not want to have mindsets that their kids and grandkids are at risk.
This is the primary obstacle to climate action.
I also think that some of the extra-rational approaches to dealing with climate policy inaction, such as mass protests based upon the limited success of the civil rights movement feed into this confusion and wishful thinking, including crazy ideas that we can solve it all by planting enough trees and banning plastic bags.
Given these sociological trends I would submit that as much mitigation should be pursued, it’s so late that substantial amouts of resource need to be put into adaptation, including reforming flood plain policy to get people to leave flood prone areas and rebuild elsewhere.
Arguments about RCPs aren’t at all to the point.
Also, having protracted duscusiions about serious matters on Twitter, really?
The RCP8.5 scenario may be correct, but the way it’s framed is all bollocks. Most people don’t realize that if we had even twice the endowment of crude oil than we do at this point, we would be in a much bigger predicament. If you look at the historical increase in crude oil consumption that occurred up to the end of the 1960’s, it’s obvious that at that rate we would really be burning to a crisp by now. But we’re not even close because crude is a finite and non-renewable resource and as soon as the market figured that out, it automatically corrected and started to throttle down on production&consumption. So at this point we are well past peak production on conventional crude oil and any future decrease based on AGW concerns will be tempered by the natural decline due to depletion. The latter is what is driving adoption of EVs as much as anything else — IOW, the market is all-knowing.
So the concerns that remain center around low-grade coal, fracked natural gas, and unconventional oil production. Like conventional crude oil, the high-grade (anthracite and bituminous) coal is all but gone and so the analysis is centered on how much lignite the world will continue to mine. Raymond Pierrehumbert is rightly concerned about the unconventional oil potential in places that contain oil shale and realizes that if this starts to get exploited (and that’s a big if) we will be entering a new era. All the water in the western USA will need to be sacrificed to extract this oil and its not clear that the decision to go that route will make any headway at all. The net energy returned will be minimal for the effort and expense to the environment, just as with mountain-top removal for coal and scraping the earth to get at Steve McIntyre’s beloved tar sands.
The way I see the RCP 8.5 scenario is that it is binary. We will never get close to that profile if we allow the natural depletion of conventional crude oil, natural gas, and high-grade coal to continue. But we may break through and surpass that trend if the low-EROEI sources of fossil fuels are exploited.
Get the opinions of any dedicated energy analysts and they will tell you the same thing.
I found that thread both less contentious and interesting. I first learned that the RCP8.5 was not an emission pathway here, so thanks for that!
And how can it not be completely reasonable to start out with a reasoned, but extreme limit, and then back away from it? I find my thinking is best when figuring out how the extreme is not plausible. It is only then that I can best rethink to see how what is not plausible is actually possible … and then, repeat. Or, at least that is my process at its best (with the least amount of motivated reasoning/observer bias).
This is what I’m attempting in my ongoing effort to quantify the Inuit hunter observations concerning what the additional refraction is a measurement for … and what of that is possibly new. And, regardless, can the import if the observations help address the 4% divergence between what the models’ average of Arctic sea ice loss is and what is being observed?
Anyway, arguing about worry over headlines garnered due to the abundance RCP8.5 model runs is mostly motivated reasoning generated. It is irrational, if engaging. I felt those headlines would sort themselves out rather easily … if academic institutions were leading the way in terms of cooperation and implementing a shared zero carbon emission business plan.
… sigh …
😉
sNAILmALEnotHAIL …but pace’n myself
https://m.youtube.com/channel/UCeDkezgoyyZAlN7nW1tlfeA
life is for learning so all my failures must mean that I’m wicked smart
>
Paul,
A key point is that the RCPs are Representative Concentration Pathways. Yes, they are associated with various socio-economic pathways, but there isn’t a unique way in which we can follow a specific concentration pathway. Most people on the thread agreed that the energy, and hence emission, pathway associated with RCP8.5 was probably unrealistic and that RCP8.5 itself was probably unlikely. That doesn’t, however, make it impossible or that we couldn’t end up following it for a different reason (under-estimating the impact of carbon cycle feedbacks or the development of unconventional fossil fuels).
Greg,
Good that someone took something useful from it.
Yes, I think it’s quite reasonable to have a range of possible pathways that bracket what is likely.
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> My impression is that we’re now in a position where people who probably mostly agree about the issues, are in conflict over details that probably don’t really matter.
It may always have been the case.
This observation takes the wind out of anyone who’s pretending 8.5 matters much:
Since CO2 emissions are still following a “burn it all” pathway, something like RCP 8.5 needs to be in the model run mix. I am willing to bet that it will soon be cheaper to use renewables even in India and China so that extracting oil from tar sands and oil shale (not fracked shale to produce oil) will disappear. Nevertheless, there are still strong forces toward burning fossil fuels.
The other reason to have the RCP 8.5 scenario is to judge to what extent we are bending the emissions curve.
I didn’t find it massively contentious. I’ve seen several comments before along the lines of ‘RCP8.5 is based on implausible coal use’ and ‘RCP8.5 is closest to where we are now’. But it’s not an argument worth having, just a chance to clarify and learn a little.
1) Michael Liebrich I hope as a result now understands that RCPs are not energy scenarios and include possible forcings resulting from carbon cycle feedbacks or other gases.
2) another misunderstanding I think is about whether RCP8.5 is ‘correct’. Isn’t asking that question itself a category error? There shouldn’t be a need to second-guess humanity’s actions (and the carbon cycle) in order to model something. All models are incorrect, but some are useful.
RCP8.5 is useful because as ATTP summarises, we ‘probably couldn’t yet rule out an RCP8.5 concentration pathway, that it was still useful for inter-model comparison, and that it was a useful pathway for impact studies because of the large signal to noise’. In a decade or two we might consider whether RCP8.5 is still useful.
3) Is a further reason that it might still be useful for looking at possible multi-centennial changes? Even if we don’t reach 8.5 W/m^2 this century, we might do next century. (They’ve been extended to 2500, but are mostly flat, clearly none are ‘correct’.)
4) Further, should we really take too much notice of the incredulity of business people and economists about energy use? ‘The greatest shortcoming of the human race is our inability to understand the exponential function’ Mike Berners-Lee gives simple reasoning for why energy use has been exponential, and why it may continue to be even with efficiency improvements.
Having said all that…
5) Presenting projections of effects to the public (hello), should the scenario be quoted as an RCP? For full transparency, perhaps. It is important to express conditionality: ‘this is not inevitable, but is the kind of thing that might be expected if [eg] current Paris pledges are fully implemented’.
I like to link social media discussions to the Royal Society page ‘The Basics of Climate Change’ (2014). That page says “If there were no technological or policy changes to reduce emission trends from their current trajectory, then further warming of 2.6 to 4.8 °C (4.7 to 8.6 °F) in addition to that which has already occurred would be expected during the 21st century”. I daresay the more vituperative contrarians would like to criticise that. Should it be expressed better?
The initial comment seems unhelpful. In my experience how a scenario is presented is irrelevant to support for climate action. What may be helpful is an wider awareness that there are multiple possible RCPs and SSPs that depend to a large extent on political choices.
RCP8.5 is not ‘bollox’, it’s a Representative Concentration Pathway.
I agree with Mitch, but isn’t “burn it all” actually worse than RCP8.5? Foster et al call that extreme scenario ‘Wink12k’ from doi:10.1126/sciadv.1500589. (BTW Deconto & Pollard found RCP8.5 melted most of Antarctica by 2500.)
Mitch said:
“oil shale (not fracked shale to produce oil)”
That’s an important distinction because whereas fracked shale oil is peanuts in the greater scheme of things, the evil oil shale may contain 4X the total amount of conventional crude available — and 80% of that is in the USA.
To be fair, the discussion has become much more constructive/interesting. Probably because one of the main protagonists decided that they’d imparted as much of their knowledge as they could, and left.
Anders –
> The idea that scientists should stop doing something in order to counter those who are clearly engaging in bad faith doesn’t make any sense to me.
Yup. There is a problem with that logic. So then it’s a matter of deciding who is and isn’t engaging in good faith.
Joshua,
Well, I guess I might regard them as two different issues. Should scientists avoid something so as to minimise the chance of it being misrepresented? In general, no, but they might consider being careful about how they present what they’re doing. Do some people engage in bad faith? The answer seems clearly to be yes.
ecoquant –
> They do not want to change their lifestyles or jobs or habits. They do not want to have mindsets that their kids and grandkids are at risk.
This is the primary obstacle to climate action.
+++++++++
The mechanisms of how people formulate their views on climate change seem rather complex to me. Just describing it as a matter of what people “want,” I don’t think, is particularly accurate. It strikes me as a kind of moralizing that is both wrongly-based and counter-productive. It rather reduces the question of policy to address climate change to an “us” vs. “them” frame that may in the end not help result in mitigation policies
Anders –
> Should scientists avoid something so as to minimise the chance of it being misrepresented? In general, no,
To make sure I get that…
Why wouldn’t you avoid something that would be misunderstood by someone who is acting in good faith? Are you saying that doing so would require you to mislead in some way, or self-censor with respect to the science?
Maybe sometimes, but I think that often that isn’t the case at all.
Oh wait…. “to avoid the chance of being misrepresented…”
Misrepresentation = bad faith. I think it’s futile to try and avoid being misrepresented by people who are acting in bad faith.
Joshua,
No, I was meaning that one might want to consider how something could be misconstrued by those who act in bad faith. I’m not a huge fan of scientists worrying too much about this; those who act in bad faith will find something to criticise. However, there are often cases where it’s possible to present information in a way that makes it difficult to misrepresent.
Joshua,
I see our comments crossed. I was responded to your earlier one.
OK. Got it now
@Joshua,
I know I sound defeatist when citing OECD collective habits, but I think I’m just saying in different words what people like Daniel Kahneman already have. I’ve been at this for 15 years, not long by some comparisons, but I’ve worked mostly among and with environmental progressives who have no doubt about the reality and severity of climate disruption. (If anything, some are overly apocalyptic.) And, as political organizations, they have carefully navigated the “art of the possible”, systematically steering clear of positions — like working to discourage people from installing new natural gas — which they know by polling to be unpopular, and working on positions which, well, how could anyone really object to marching in the streets and making plastic bags Satan”s spawn? They also oppose hydropower and gas pipelines and gas compressors, but not municipal provisions to ban solar farms nearby or remove wind turbines that have already been built.
Yet people moan and complain about how horrible climate disruption will be, about the need for climate justice, all while each driving alone in their CO2 spewing cars to weekly action meetings.
Mitigating emissions needs to be uncomfortable and disruptive. Anything else won’t do the short term.
Okay, I understand it”s hard. But, then, let’s be realistic and admit we are headed to +3C or +4C by the time all the fossil fuel infrastructure in urban spaces and the like is switched off, figure out how we are going to do that, adapt, and think about, study, and plan how we do direct air capture and sequestration economically, and not kid ourselves about planting trees. (See recent https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2018JG004917 and related.)
What is the correlation between people who object to scientists giving consideration to the worst case scenarios and those who want to have no regulatory constraints on fossil fuel use, and, having their way would make that objectionable worst case scenario more likely? Seems to me there is an unhealthy lot of overlap.
“What I found frustrating is that I think this is an interesting/important issue and it would be worthwhile to be able to discuss it sensibly. “
Indeed, the eye-opener for me was having a leading mainstream climatologists engage in the sort of evasion and playing to the gallery that you see at WUWT rather than acknowledge that the statistical evidence (which AFAICS is essentially all we have) for the existence of a pause was not statistically significant. It isn’t even as if it is a big deal that it is not significant, it just means that a degree of circumspection about it is required.
Although Twitter doesn’t seem to encourage considered discussion, nobody is being forced to engage in worst sort of rhetoric rather than seek the truth/agreement/understanding. We bring that with us ourselves.
for the existence of a pause was not statistically significant. …
Because that may have been dumb luck.
Indeed, doesn’t mean it wasn’t worth studying though (as I pointed out at the time). It isn’t only skeptics that have problems with self-skepticism, apparently.
In other news, scientists are being blamed for stuff they didn’t do:
So the year is 2030, Emissions have peaked.
Renewables continue their increased penetration.
Trump is just a bad memory.
everyone is on board.
We are already seeing increased damages from climate change.
we all see the damage.
And ATTP is still suggesting we study RCP 8.5 because
” we probably [can’t] yet rule out an RCP8.5 concentration pathway, [and] it is still useful for inter-model comparison, and .. it is a useful pathway for impact studies because of the large signal to noise.” And further there is no telling, maybe all of humanity loses it’s fucking mind and agree to burn it all. not impossible of course.
Ya know at sometime in the future RCP 8.5 has done its job. Even if it’s job was scaring folks into action,which is not necessarily a bad thing.
Seems to me like a lot of people are being overly on-the-defence about RCP8.5 due to the vociferous and insulting speech of a few who seek to dismiss it, even though their arguments at best amount to little more than personal incredulity, and are often demonstrably false. It’s not inarguable but I don’t really see a strong basis for even calling it a “worst case” or “extreme” scenario. This isn’t something cooked up by AMEG or Greenpeace. It’s a level of fossil fuel usage which has routinely come out as a plausible future in every round of mainstream economic scenario analysis over the past 30 years. Certainly it’s towards the upper end, although how far towards is a matter of debate.
Leibreich’s main point appears to be incredulity over coal growth in most RCP8.5 scenarios, which he expresses in three main forms:
1. Repeating the required multiple of coal consumption per year (7x). This is simply stated as if it must be obvious to anyone that it can’t happen even though coal consumption has increased by 5x over the past 100 years and he doesn’t provide any evidence at all for why it can’t happen. It should also be pointed out that the multiple is a bit misleading – it refers to 2100 consumption vs 2000 consumption in the scenario. RCP8.5 2100 consumption vs. actual consumption today is about 5.5x (from memory).
2. Pointing to a graph of recent global coal consumption and suggesting that it “looks like” it has peaked. Trouble is, global coal consumption “looked like” it had peaked in the early 1990s and yet it is now nearly double the 1990 figure.
3. RCP8.5 starts replacing oil with coal for production of liquid fuels around mid-Century due to diminishing oil supply. Leibreich appears to argue that this oil shortage is not realistic, and in fact oil is/will be far more abundant than assumed (although he also seemed to separately argue that liquid fuels would be replaced by electric). Trouble is, more fossil fuel supply increases the likelihood of RCP8.5 happening, it doesn’t decrease it. Yes, increasing the fraction of oil and thereby decreasing the fraction of coal does delay things, but not for very long. I did a simple calculation a while back for what would happen if all the coal in RCP8.5 was replaced by natural gas (based on a few people claiming that natural gas was abundant enough to totally replace coal around the world and somehow that would prevent RCP8.5) and found that it would only delay hitting RCP8.5 level 2100 CO2 by ~25 years.
To put that another way, there is a mythology about RCP8.5 that it’s all about coal. And yes, almost all (all?) RCP8.5 level scenarios do require large increases in coal consumption, but that’s only because oil and natural gas are assumed to start running dry by mid-Century. If that’s not the case then we can very easily hit RCP8.5 with a much smaller coal consumption increase, and with a delay of only a decade or two, if that long.
A lot of people seem to miss the woods for the trees on this topic. Simply put, if our energy demand keeps growing at its historical pace while the fraction of demand supplied by fossil fuels remains at a similar level then we will hit a level very similar to RCP8.5. Whether that’s before 2100 or a few years after, based on the specifics of the gas/oil/coal mix, doesn’t seem that important to me.
Steven Mosher,
So the year is 2030, Emissions have peaked.
Renewables continue their increased penetration.
Trump is just a bad memory.
everyone is on board.
But this is an entirely separate point from that which seemed to be being made by Leibreich et al., which is about the plausibility of RCP8.5 without mitigation.
You’re saying following a policy-driven mitigation pathway will ensure missing RCP8.5, and I think everyone would agree with that. The problem with your argument is that you assume the mitigation before it’s happened.
Ya know at sometime in the future RCP 8.5 has done its job. Even if it’s job was scaring folks into action,which is not necessarily a bad thing.
Well, yes, that seems obvious. But that point is certainly not now.
Since I don’t share Paul’s view about the amount of O&G remaining, I’m far less complacent about RCP8.5 being unattainable without going back to massive coal burning or pursuing oil shales. Although there may be come cancelling out wrt to CO2, because I would see shale oil being produced by underground retorting not in surface furnaces, so less product stream available but most of the CO2 spent producing it would stay underground, but more fracced oil shale available, with a low energy overhead in production. But let’s not go round those houses again.
As others have said, the RCP doesn’t specify how it gets there. Fossil fuel consumption, Arctic fires, thawing permafrost or bubbling clathrates. The RCPs don’t care which. As well as Andrew Dessler’s points, I also see value in driving models beyond the maximum range you expect to apply them to in the real world. I routinely did that with my geological basin models. It’s how you know where they deviate from linear to non-linear behaviour, or cross a threshold or tipping point. Or where your solver explodes 😦 . It can also raise insights into some fundamental aspect of the model or of the system it represents.
It’s important to know that none of those things are happening close to your range of interest. Because if they are, it raises concerns that the threshold is in the wrong place and there should be nonlinear behaviour in your range of interest. That sort of stuff does need to be published so that intercomparisons can be made. Do non-linearities arise at the same place in all models? Do some or all develop bifurcations? There’s a fair bit of that done in Snowball or Slushball Earth models, often using unrealistic parameters (modern continental configurations and CO2 but a dim sun) because everyone can run with the same starting observations, not make their own educated guesses about conditions 700 My ago. You can of course choose how much of that gets discussed in the non-specialist literature, what goes into press releases, etc. But until such time as we’ve deviated detectably from RCP8.5, I would continue to discuss it in the mon-specialist literature.
SM “And ATTP is still suggesting we study RCP 8.5 because [something inconsistent with the scenario set out immediately above]”
ATTP wrote “What I found frustrating is that I think this is an interesting/important issue and it would be worthwhile to be able to discuss it sensibly.”
Sigh.
“To put that another way, there is a mythology about RCP8.5 that it’s all about coal. “
Yet Ken Caldeira provided this non-mythological chart:
and this one
Yet Ken Caldeira provided this non-mythological chart
Well, that was my point. Yes, reaching RCP8.5 level is about coal if IF reserves of oil and gas are as low as typically assumed in IPCC scenarios. But there seem to be a lot of anti-RCP8.5 people who genuinely argue that RCP8.5 won’t happen because coal will be replaced by an effectively never-ending oil and gas supply. And they base that assumption on the mythologising of RCP8.5 being “all about coal” even though if they actually bothered to run any numbers on it, it really doesn’t make a huge amount of difference whether it’s coal or oil or gas.
Steven,
No, I’m really suggesting we study RCP8.5. I’m mainly responding to claims that it’s “bollocks”. I also don’t think we really get to tell scientists what they should, or should not, do. However, if we want to better understand the impacts of substantial warming (which could occur because we follow a high emission pathway, or because climate sensitivity is higher than we think) then it’s useful to run models with a high forcing pathway as input.
Paul,
Yes, this certainly influenced some of the responses (mine included).
I was wondering something similar myself. If the world economy keeps growing at 2-3% per year then it will be 6 to 10 times bigger in 2100 than it is now. RCP8.5 emissions go up by about a factor of 2 – 3. So, how do we avoid this kind of emission pathway (as many seemed to claim was virtually certain). Is it simply energy efficiency and alternatives that will dominate in the second half of this century? I really don’t know, but it does seem that we will need to start implementing various alternatives pretty soon if we want them to dominate to that extent within the next few decades.
Dave said:
Why not discuss this? The info that is given to the public concerning oil is constantly changing, largely because of the amount of leveraged investment that has gone into exploiting shale oil. Investors eventually want answers to questions concerning what black-hole their money disappeared into.
This article from yesterday discusses the prospects for further growth and provides examples of the marketing hype that has not panned out: Permian Slowdown Could Start In 2020
Ecoquant was writing well until glibly suggesting that we are ‘committed to a 3-4 degree rise and will just have to adapt’.
It won’t be that easy, Eq. Indeed, we are entering into uncharted territory if we pass 2 degrees. Already the effects of around one degree of warming in terms of extreme climatic events are pushing species to and beyond their adaptive limits are being recorded.
People write about adaptation as if the rules governing the functioning of ecosystems are irrelevant or that our utter dependence on them is unproven. Of course, both are absurd notions. Humans exist because natural systems generate a range of conditions that permit it. A 3-4 degree rise this century will wipe out very many species. We will not be far behind.
So forget about simple notions like human adaptation to a 3-4 degree rise in surface temperatures across the biosphere this century. If this happens, we will be facing our own extinction. As natural systems collapse arpund us, our fate is sealed.
So on this point, Ecoquant is very, very wrong. Talking about adapting to such a scenario is very reckless.
@JeffH,
I know the consequences and dangers of what a +3C to +4C increase might be, and what will probably be required (Hansen, Kharecha 2018). But, there’s this, recently presented by Dr John Holdren (July 2019):
based upon a paper by Fawcett, et al from 2015. Present facts are that the INDCs are at risk of not being accomplished. I’m not giving up. I’m simply saying that based upon the evidence of collective ambition to do or not do something about the problem, the best current forecast is as I wrote. There’s probably evidence in Fawcett, et al for a higher destiny as well.
“But this is an entirely separate point from that which seemed to be being made by Leibreich et al., which is about the plausibility of RCP8.5 without mitigation.
You’re saying following a policy-driven mitigation pathway will ensure missing RCP8.5, and I think everyone would agree with that. The problem with your argument is that you assume the mitigation before it’s happened.”
Mitigation is already happening, well not so much in china and India.
But my point is a bit more subtle.
we believe in the science that means we will continue to see damages year after year.
by 2030, or say by 2040 or even 2050 as we see the predicted damages by 1.5C,
then to believe in RCP 8.5 you have to believe that humanity will see these actual
damages and Then double down and continue to emit like there is no tommorrow.
If you think humanity is that irrational then, it is really pointless to engage in rational
discussion. You are basically arguing that humanity will see the damages grow
year after year and do nothing. SO in addition to being highly unlikely
from a “sources of carbon” perspective, it is highly unlikely from a human behavior
perspective.
but is DID make sense to run 8.5. It served a purpose and will continue to serve a purpose
Those AR5 runs of 8.5 wont disappear. We know and will continue to know that 8.5 is
dangerous. Going forward there comes a point at which studying the boundary case is
NO LONGER MEANINGFUL OR PRACTICAL. So imagine it is 2030. Imagine we have
everyone on board and have turned the corner ( my hypothetical)
In my hypothetical (2030) ATTPs’ “reasons” for doing 8.5 are still “valid” Lets make it sillier
Its 2070 and we are at net 0. Using ATTPs justification for 8.5 we could still justify
it. Recall the reasons for doing it
” probably couldn’t yet rule out an RCP8.5 concentration pathway, that it was still useful for inter-model comparison, and that it was a useful pathway for impact studies because of the large signal to noise. ”
So in 2070, we are net zero. And still at that point you could not “rule out 8.5” it would still
be useful for intercomparions ( nobody actually DOES THIS) and i would still have a high signal
to noise.
Bottom line: 8.5 has served its purpose. Time to devote wall time to other scenarios.
” I also don’t think we really get to tell scientists what they should, or should not, do. However, if we want to better understand the impacts of substantial warming (which could occur because we follow a high emission pathway, or because climate sensitivity is higher than we think) then it’s useful to run models with a high forcing pathway as input.”
we most certainly DO get to tell scientists what they should or should not do: emit less, eat less meat. avoid single use plastics. and dont waste your wall time.
@Steven Mosher,
In the context of climate disruption “avoid single use plastic” is really, really small potatoes and, in terms of life cycle sustainability costs focussing upon imparted emissions, plastic can be a really good material. Compare paper and glass.
Also, what’s not appreciated in the hordes of people opposing plastics is that they are consumed by microbes in oceans. “Microbes don’t spurn a free lunch.” (Chris German, WHOI) That something like this had to be true has been known for many years, because otherwise mass balance from sea assays and inputs to oceans could not be explained. But now we know the microbes that do it.
Also, one of my favorite means of doing Carbon sequestration is capturing CO2 from atmosphere, turning it into plastic, and then burying the stuff deep in non-aqueous landfills. There the microbes that do degrade plastics can’t operate.
@Steven Mosher, some quick references and, in particular note Syranidou, et al:
* Praseetha, et al, 2016
* Jacquin, et al, 2019
* Syranidou, et al, 2019
* Pathak, 2017
* Balasubramanian, et al, 2010
* Solé, et al, 2017
* “Plastisphere”, WHOI, 2013
* https://www.whoi.edu/know-your-ocean/ocean-topics/pollution/marine-microplastics/“>”Marine Microplastics”, WHOI, 2019
Andy Skuce for the posthumous win:
https://andthentheresphysics.wordpress.com/2015/07/26/is-this-the-latest-tactic/#comment-59584
I miss Andy.
Steven,
They don’t always have to listen. This is not to say that the suggestions aren’t sensible, it’s just that sometimes scientists keep doing things even if others think they should move onto something else.
Richard Betts made the point that Helix is going to present their analysis on the basis of impacts at different levels of warming. Seems quite reasonable to me. It wouldn’t surprise me, though, if they use an RCP8.5 concentration pathway to produce the higher levels of warming.
Likewise.
“All future scenarios appear highly implausible to me. By directing our incredulity at just one of them, perhaps we reveal more about our prejudice than our judgement.”
the lack of people saying RCP 2.6 is implausible being a good example, it seems at least as implausible to me in the current political climate than RCP 8.5. However I freely admit to having little knowledge of this and I certainly am not going to armchair quarterback the scientists [social and otherwise] or economists on this one.
We have a discrete range of scenarios because we can’t run simulations for every eventuality that individuals think are most likely. Having a discrete set of scenarios ranging from borderline impossibly optimistic to borderline impossibly pessimistic means we have bounds within which to work and a couple of interior points for interpolation. Seems pretty rational to me.
“I miss Andy.”
me too.
It is a shame that so much of this is about “framing” or “messaging”, rather than just rational discussion. The fact that those things are apparently important is part of why I am not particularly sanguine about anything actually being done.
If people are really susceptible to this kind of sophistry, we are doomed, doomed I tell ye (in the words of Private Frazer)
N.B. @past_is_future had just said ‘There is not an “ECS dial”.’
Looks to me we are burning stuff as if there won’t be a tomorrow…
https://www.forbes.com/sites/jamesconca/2019/07/20/so-you-think-were-reducing-fossil-fuel-think-again/
Which emissions pathway is that?
Paul, “Dave said … Why not discuss this?”
Because we discussed it ad nauseam months ago, and I provided a lot of information, based on a lot of effort checking sources, which you dismissed or ignored. So I don’t want to waste our time or anyone else’s time by going there again. I simply wanted to register my view that we can’t rely on Peak Oil and no coal to save us from RCP8.5. If I’m right, we’ve instituted a carbon tax and other measures to ensure a low-carbon future, whether there’s more O&G out there or not. If you’re right, we’ll also have saved ourselves from an energy crunch when the O&G runs out. But if everyone believes you, lots of people will say “no need for those measures, the Invisible Hand Of The Market will provide, let’s just do BAU until the O&G runs out”. Under those circumstances, if you turn out to be wrong … OOPS! Prudence dictates that we act as if I’m right, even if I’m wrong.
“we most certainly DO get to tell scientists what they should or should not do: emit less, eat less meat. avoid single use plastics. and dont waste your wall time.”
I do think this unreasonable demand for personal environmental purity has arisen from the demands of self appointed Hypocrisy Police – who (hypocritically) expect those things of people who care and seek change but not of those who do not. Yet in the knowing better but doing it anyway stakes that barely rates compared to people in positions of high trust knowingly undermining public trust in climate science and promoting the very industries and activities that make things worse. In our governments and leaders “not caring” – and using that not caring to sustain responsibility and accountability avoidance on industrial scales – is negligence and moral failure written bold.
As admirable as making an example by “going without” can be, going without is not the economy wide change that is being called for and no-one should have to go Stone Age to have their concerns taken seriously; in my case my concern is wanting governments and leaders to take the expert advice seriously, not take my word for it, like they can throw this to a public vote to decide if they will act responsibly or not. I’m not convinced that “going without” is or should be the principle message of climate activism; some extreme environmentalists may have that as a primary solution but the climate “movement should make doing energy abundance by other means it’s principle way of making it’s point.
Whilst the calls for economy wide efforts to reduce emissions from concerned scientist (and concerned citizens) are true enough our governments and leaders already know the problem is real and serious. If responsibility for fixing this is loaded entirely onto those who care – rather than those who sit in the very Offices where decisions are made, who have responsibility – we will fail.
Dikran,
As I think Peter pointed out on Twitter, it is rather bizarre that someone who has been involved in this topic for decades didn’t realise that climate sensitivity is an emergent property of the models (and also, how much flax climate scientists would get if they were explicitly tuning to a sensitivity).
ATTP: I miss Andy.
Seconded. I think I mentioned before that I worked with him for a couple of years in the early 80s. He was a nice guy in person, as well as online.
““we most certainly DO get to tell scientists what they should or should not do: emit less, eat less meat. avoid single use plastics. and dont waste your wall time”
Aren’t climate skeptics always telling scientists not to perform adjustments on instrumental climate observations? ;o)
ATTP, indeed, I replied with pretty much exactly that point before I got to Peter’s reply ;o) I also pointed out that projections are conditional predictions, if X then Y and the RCP is the X, and so can’t really be “tuned”, so that suggests a misunderstanding of the application of models as well.
Dave,
I don’t recall you mentioning that. Thanks.
RP Jr. doesn’t seem to understand the difference between predicting what people will do, and elucidating the laws of physics.
Perhaps social and political science need to invent a different word for the second part of their name?
@mrkenfabian,.
Unfortunately, the mis-messaging has now been joined by active efforts to disrupt mitigating responses, with 45’s BOEM having stepped in and suspended approvals for East Coast wind farms on an unspecified and indefinite timetable until they perform a “comprehensive review” of all such plans along the coast. There are projects, like Vineyard Wind, which are now delayed pending such a review, and the costs incurred keeping everyone ready to move forward are, by some accounts, moving into a region where they risk project viability.
David B Benson said:
That’s the bubble in USA fracking that will crash in a few years. The mainstream business press is always behind the curve on this stuff.
What’s interesting about the ongoing RCP8.5 twitter thread that people are complaining about that “won’t die” is that specialist fossil fuel analysts are involved, people like Chris Nelder and Glen Peters.
Lacking is a systems view of things and perhaps David MacKay is the guy that is sorely missed.
The perspective of the energy systems modelers above is ironic; from what I’ve seen energy systems model predictions are generally bollocks. Can’t get the price of the incumbent fossil fuels right a couple of years out, much less the relative economics of the competing pathways.
Chubbs, Predicting the fuel price is game theory, which is known to be intractable to model. But projecting depletion is geology, which is possible since fossil fuels are a finite and non-renewable resource. Earth scientists did get that aspect right.
Is there a plausible case that most of the coal is ‘too difficult’ to extract? If you assumed that there wasn’t any other reasonable energy source, and people didn’t care about CO2 or pollution, you could imagine the world running mostly on coal (or coal-derived gas), even if it tripled in price.
There is a lot of easy coal around, and if most of it can be extracted, you are pretty much in RCP8.5 even if there isn’t much gas/oil used.
On the face of it, is seems plausible physically, even if there are economic/social reasons that it probably won’t happen. And that seems sufficient to justify keeping it as the high-end scenario.
Paul – Finite and non-renewable is a low bar for getting it “right”. How much fossil fuel will be used between now and 2100 is a different kettle of fish.
Chubbs, It’s a low bar that’s for sure. Yet, there’s a paucity of applied math on how to estimate reserves, which is the rationale we used to get our book on the topic published.
Recall that this was Liebreich’s rationale for his “bollox” claim :
Ben said:
What kind of coal? Lignite? No wonder there are so many Australian deniers on Curry’s blog
> There is a lot of easy coal around, and if most of it can be extracted, you are pretty much in RCP8.5 even if there isn’t much gas/oil used.
Paul S got us covered more than one year ago:
https://andthentheresphysics.wordpress.com/2015/07/26/is-this-the-latest-tactic/#comment-59584
The main problem we’re facing is capacity. Suppose there’s a solar panel or a wind mill everywhere possible, and abstract away all other renewable sources. What will guarantee that this will meet demand? If it does not, then fossil fuel will return.
Besides, the luckwarm gambiteers won’t stop if 8.5 gets deprecated:
There’s no reason to expect them to stop looking for the lowest bound of sensitivity justified disingenuousness can buy.
I point at this:
And I point at this:
That is all.
I guess what I was looking for is if there are serious resource limits on coal at ‘reasonable extraction costs’: i.e., not too much higher than current oil or gas prices per unit energy.
I agree from Paul S that from a demand perspective the world could quite reasonably consume 10x current coal usage. What about supply? (he did ask that question in his comment)
Paul P: Hard Coal, Lignite, Peat, and everything. Both ‘conventional’ and ‘weird hairy’ coal. Left to their own devices, people seem happy to burn almost anything.
There is quite strong disagreement on whether coal has ‘peaked’, and this anyway doesn’t say much about resource limits by itself. That is, trends in coal usage might depend strongly on other forms of energy becoming cheap (gas, renewables), and policy (carbon prices etc) and not simply on extraction costs.
According to my sources, humans will use 3,000 Quads by 2075, and if they all come from coal we’re ruined. This implies that there’s at least 3K quads of coal lying around.
Here’s a chart:
Source: https://www.eia.gov/todayinenergy/detail.php?id=2930
So we have the USA, China, Russia, Australia, India, and the rest of the world.
Where is right-wing populism pushed harder, again?
***
As far as I can see, the “but peak coal” argument has a similar form as “but da paws.”
Yes, coal is the “go to” fuel in these discussions, as you can see in my link to Ken Caldeira upthread. The question is will Australia put the breaks on its coal export bonanza (4x the USA)? That may be part of the “international cooperation” that Liebereich is referring to.
ML has finally come full circle in the #ButCAGW ringmarole:
I point at this…
Looking at Figure S5 in the paper, it appears that their median CO2 emissions projection has practically peaked already. In other words, they’ve effectively pronounced that the end of the fossil fuel era has already begun, which seems quite important. Their model assumes that almost all future energy demand growth will have to be driven by non fossil fuel sources. What those are, and whether those sources are any more plausible than fossil fuel sources, do not appear to be considerations included in the model. It just assumes that energy demand transitions to… something. In fact, oddly energy demand doesn’t appear to be a part of their model, so it’s not even clear how much additional energy these other sources need to produce to satisfy growing demand, and whether or not that’s “plausible”.
Maybe all futures are implausible.
> Maybe all futures are implausible.
This would make a nice tee:
Each specific future line is quite improbable, that’s for sure.
I guess I should have looked that up: even the economically and technically feasible coal reserves are plenty to take us up to RCP8.5. Never mind any additional resources that might become technically possible to extract later on. Or any other fossil fuels. Or ocean/forest uptake changing.
So arguing that RCP8.5 is impossible is simultaneously believing that humans aren’t stupid enough to burn all the coal and that climate scientists shouldn’t warn anyone about what would happen if we did burn all the coal. Or that most people will stay poor maybe?
Reminds me of measles vaccination, where people argue it isn’t necessary because of the low incidence of measles.
Yes, the weighting toward coal is very lopsided, and it leads to the conclusion that much of this coal will be converted to a form that crude oil is normally used for, namely transportation. So that will be either electricity for EVs or into a replacement liquid fuel.
It will be interesting to watch the reporting of fossil fuel production given the way that the categorization for oil has changed. The energy agencies have modified their measure of the “crude oil” category to be now called “all liquids” which can allow liquid fuel such as biofuels and coal-to-liquid (CTL) or (in cases) liquified natural gas to be counted as crude oil. But unless this fraction of CTL is removed from the “coal” production numbers, there is a danger of double counting of emissions.
This is also one of the reasons that the date for peak oil is a bit slippery.
no individual value from a continuous distribution is plausible, perhaps we should integrate over a distribution of RCPs? ;o)
… of course one way of doing so would be to perform a weighted average over discrete RCPs that span the RCP-space, perhaps arranged over a regular grid (intervals on a 1-D space) each separated by say 2Wm^2 ;o) ?
I think there are people – with a much greater say in this than anyone commenting here – who see RCP8.5 as a God given right. Australia’s current government appear to be amongst them. Whether that right ultimately gets exercised becomes the question but if not it won’t be for lack of their trying. We discount the power and influence of the proponents of fossil fuels at our peril – with the risk of international climate negotiations breaking down. It seems RCP8.5 is only a question at all because wind and solar do work as disruptively well as they do – and whoever expected that?!
Easier to see “bollocks” with the benefit of hindsight. Coal has lost competitive advantage since the RCPs were to developed to gas, wind and solar. Improving economics for wind and solar, in particular, make it easier to leave some coal in the ground. So I could agree that RCP85 CO2 emissions are less likely now. On the flip side RCP85 is doing much better than the other RCPs on methane.
Chubbs,
Coal consumption growth to date is in-line with Riahi et al. 2011 RCP8.5 and well above SSP5-8.5. It seems easy to forget that the plateau was immediately preceded by the largest coal expansion in history.
If you look at the Riahi et al. 2011 energy data it’s actually natural gas which has fallen short, I guess contrary to what most people would think. In the mid-2000s most projections made suggested that natural gas should have overtaken coal in terms of global energy production by now.
Coal consumption growth starts to really take off in these scenarios from 2040, due to oil and gas discoveries no longer being able to keep up with energy demand growth.
This curve for expected CO2 emissions growth would have benefited from realistic predictions for oil production. M. King Hubbert made his first prediction in 1956 that US oil would peak around 1970, which wasn’t that far off — while Revelle and Seuss made their prediction in 1957, which Glen Peters mentioned.
I think the basis of the entire RCP8.5 tweetstorm lies in the fact that climate scientists and energy analysts haven’t been working as well together as they should be.
paulski0 said:
That’s misleading. Year-to-year oil discoveries haven’t kept up with yearly production for a long time. Everyone should be aware of this situation just as everyone should know that CO2 is a GHG.
PaulS – True, but what ML didn’t communicate very well is that we are nearing a point where the energy system past doesn’t predict the future very well. Solar and other non-fossil technologies are on learning curve economics with improving costs, while fossil fuels are on resource depletion economics with increasing costs.
Chubbs said:
“fossil fuels are on resource depletion economics with increasing costs.”
True. The current shale oil price is completely underwater. That makes the whole idea of predicting price moot. We’re apparently at the point of subsidizing the USA oil industry to maintain our MPG lifestyle
https://www.desmogblog.com/2019/08/08/bleak-financial-outlook-us-fracking-industry
@Paul,
(Hi!)
We are certainly socializing risks of owning property in flood prone areas, even commercial property rented out. See Prof Rob Young’s work: https://www.linkedin.com/in/rob-young-68a44339
And we certainly give fossil fuels all kinds of benefits we don’t give other businesses … Natural gas pipelines can proceed by eminent domain rather than having to buy land like railways do.
– Jan
Paul P,
I think the basis of the entire RCP8.5 tweetstorm lies in the fact that climate scientists and energy analysts haven’t been working as well together as they should be
I’m not sure that stacks. The RCPs and SSPs weren’t created by climate scientists. They were built by energy analysts and economists. Perhaps the disconnect is really between different energy analysts?
Year-to-year oil discoveries haven’t kept up with yearly production for a long time.
I’m not sure of the specifics of discovery in RCP8.5 but I think the point is about whether or not discoveries are happening enough to allow production to meet continuing demand growth in a given year, not whether there is as much discovery as production in a given year. For example, I believe production can keep meeting growing demand with zero discoveries for the next decade or so.
It might be time to issue our recurrent reminder:
“Perhaps the disconnect is really between different energy analysts?”
Certainly, because the nameless bureaucrats at the EIA and IEA tend to be too optimistic, which can be shown from their track record.
“For example, I believe production can keep meeting growing demand with zero discoveries for the next decade or so.”
You’re now changing from the concept of discoveries to that of reserves. By definition, there is always enough reserve to meet production every year (until reserve reaches zero), and with a buffer, certainly this can be extended as you say.
Willard:
As you know, ML addressed your point directly when your chalkboard message was made to him in the very same tweet thread you display.
“I know. But if every single SPS leading to RCPs 8.5 is characterised by dramatic increases in coal use, and we already know they are not going to happen, it’s not up to me to explain exactly where the errors lie. RCP 8.5 is bollox, try as you like to scare people with it.”
Paul, the issues impacting the US oil industry are low prices. Low prices for oil are not a signal of a lack of oil. China imports 281 million tonnes of coal a year. The only thing that could limit global warming is providing China with an alternative that is actually disruptive, rather than hoped to be disruptive.
jeffnsails850 said:
” Low prices for oil are not a signal of a lack of oil. “
Now you understand why fracked shale oil is piling up huge amounts of debt. It’s a stop-gap source of oil and it’s expensive to extract. Consumers are expecting to pay the same for this oil as conventional so when that happens, the investors are left in the hole.
“China imports 281 million tonnes of coal a year.”
And Australia provides >37% of the world-wide exports. Curiously, could be as many as 1/3 of the frequent commenters on Curry’s blog over the years are from Australia. I noticed this when I used to comment there, and notated a list that would make for a good sociological study.
https://asia.nikkei.com/Business/Markets/Commodities/Coal-expected-to-be-Australia-s-most-valuable-export-in-2018-19
without googling,
tell me two consequences, damages, impacts, that happen in rcp 8.5 and not
in rcp 6….
that ole extra signal to noise should pull out something… quick what was it..?
what specifically did we learn from rcp 8 that we didnt also learn from rcp 6.
the worst case scenario is so crirical that all of must know this off the top of our heads..
> ML addressed your point directly when your chalkboard message was made to him in the very same tweet thread you display.
What I recall is a response as empty as yours, JeffN.
Here’s ML today:
> what specifically did we learn from rcp 8 that we didnt also learn from rcp 6.
what specifically did we learn from rcp 6 that we didnt also learn from rcp 8.
RCP 8.5 WAS the track we were on, and NOW it represents a world avoided, something that is useful to know
Dr John Holdren used this, but I’m sure it did not originate with him:
I’m glad Eli pointed out we’re off the RCP 8.5 walking-of-the-plank, so we’re constrained to be less than +5C. Terrific.
SM “tell me two consequences, damages, impacts, that happen in rcp 8.5 and not
in rcp 6….”
straw man. Even if the differences are quantitative rather than of a different kind, that is still useful information. Also we can’t work out the consequences damages and impacts until after we have run the simulations.
Having said which, I suspect we are much more likely to see a carbon cycle response from e.g. melting permafrost in RCP 8.5 than we are under RCP 6. “tipping points” are like that, you are O.K. until you prod the climate system just a little bit too far. Again, the models can’t give us information on that without actually running the scenarios.
Eli – Yes, hard to know what “BAU” would be with various levels of government intervention for a wide range of reasons: economy, industrial policy, energy security, air quality, and even climate occasionally.
“And Australia provides >37% of the world-wide exports.”
If a “good” politician in Australia decided to shut down China’s energy supply tomorrow, some fossil fuel interests in Australia would certainly be unhappy. Anyone else? Think in terms of a big, communist nation with a large army, navy and nuclear weapons.
jeffnsails850, China is doing a good job in shutting down their nasal passages all on their own, LOL.
Related to assumptions about the future which underlie arguments about the appropriateness of different concentration pathways.
https://www.vox.com/platform/amp/energy-and-environment/2019/8/15/20805136/climate-change-fracking-methane-emissions
@Joshua,
Concur and underscore. The recent Plant, Kory, et al paper (which hasn’t Howarth as co-author) in GRL shows how serious the problem is. Leaks of “natural” gas are now known to cause health problems as well as harm trees and cost ratepayers a lot of money. These are reason enough to fix them. But doing so is considered impractical and too expensive. And even coordination to fix when a trench is open for orher work is considered too hard.
And I haven’t mentioned radiative forcing yet.
Indeed, even with coastal risks, our coasts are appreciably exposed from present day risks, let alone what SLR and extreme precipitation might bring. Storm water management infrastructure is woefully inadequate for these. No one is demanding sensible things be done.
ecoquant –
Since someone linked a comment from Judith’s, I went over there to see what was going on.
Of course, I shouldn’t be surprised by any of this anymore, but I when I think about potential new understanding of methane from fraking, I really was struck by the lack of insight many “skeptics” have into their own arguments.
I am thinking here, specifically, about the amount of overlap between the “They’re trying to silence us”/”Think of the uncertainties” crowd, and the “We shouldn’t be looking at high concentration pathways projections crowd.”
I’d leave a comment to that effect over at Judith’s, but the “Bur Real Climate moderation” and the “Thank god Judith is so open-minded” crowd also overlaps with the “Put those trolls in moderation” crowd and I have a hard time getting comments through over there. 🙂
S-o-o-o-o-o-o-o-o-o-o, if humanity burns down all the tropical rain forests in the next 80 years, I think that is called LULC, does that mean that an RCP 8.5 like scenario is still off the table?
I think that is called part of the overall carbon cycle, and eliminating the current net CO2 land sink would be something that should be covered in a storyline-like Shared Socioeconomic Pathways (e. g. SSP).
So my question is … is it? Because it should be, given what is happening in Brazil today.
I think that I’ve been saying this for awhile, I can’t possibly be the only one though.
It is the overall carbon cycle stupid.
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