RCP8.5 – another update

In case anyone is interested, Zeke Hausfather and Glen Peters have a Nature comment about the whole RCP8.5 issue. Unfortunately, they used misleading in the title, which seems to have produced an unfortunate headline on a BBC article. Otherwise, Zeke and Glen’s article is pretty reasonable.

Most of the continued social media discussion is not, though. There do seem to be a large number of people who have strong views about how science/research should be done, while illustrating a lack of understanding of how it actually works. If you’re going around telling people in other disciplines what they should, or should not, do, you’re probably mostly demonstrating your own ignorance.

There are also a couple of other comments about this. Gavin Schmidt has a Realclimate post that largely echoes my views. “Okay, fine, let’s stop using business as usual. Is that it?” Michael Mann also has a short response.

I still find this entire discussion very unfortunate. There were far more constructive ways in which it could have been conducted. I get the impression that some think that they tried this and it didn’t work, so feel that a blunter, more divisive, style was warranted. The problem, though, is that this then ignores the possibility that the original argument wasn’t as convincing as it might have seemed. We all have a tendency to think that our arguments are well thought out and correct. We can’t all be right.

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65 Responses to RCP8.5 – another update

  1. My impression, which may be wrong, is that a great deal of this discussion is ideological (don’t trust people who are claiming to simply be fighting for the intergrity of science, IMO). There are some who think it’s important to highlight worst case scenarios in order to motivate us to avoid getting there. There are others who think it’s more important to highlight that we’ve probably already done enough to avoid these. I can see merits and problems with both arguments. The former could highlight how terrible things could get, but could then lead to despair, while the latter could highlight how much we’ve already done but could lead to complacency.

    My own preference would be to be willing to consider the nuances of the situation. Yes, RCP8.5 has become much more unlikely, but it’s still a useful worst case scenario and there are still valid climate modelling reasons for using it. However, it’s also important to recognise that our current trajectory is probably not taking us along an RCP8.5 pathway. Let’s use this to highlight that our choices can influence the pathway we end up following and try to do even better than our current trajectory suggests, while not ignoring that stupid future decisions – and potential carbon cycle feedbacks – could still take us back onto a higher emission pathway.

  2. David B. Benson says:

    Just 3 K, that is, 2 K more than now, is already a catastrophy. Extensive sea level rise, more damaging storms, expanding deserts, …

  3. Re: the BBC headline, if something is “exceedingly unlikely” then something else must be exceedingly likely. What is missing is that most forecasts of fossil fuel supply have been overly optimistic, and the exceedingly likely reality of peak oil predictions (i.e. non-bureaucratic) have started to emerge.

    Anthropogenic climate change is bad for the world, while the rapid depletion of fossil fuels and especially crude oil is bad for the global economy. Pick your poison and so the only option is to move to alternate and renewable sources of energy. I asked Glen Peters about why peak oil is not mentioned in the Nature commentary and he responded that he has mentioned it elsewhere.

  4. BBD says:

    You missed off >90% reef die-off and the vast bite that will take out of the underpinning of the global marine ecosystem.

    Not to mention the relentless attrition of food security triggering refugee surges, war, pestilence etc.

    So yes, I’d be inclined to agree with ATTP. The use of ‘misleading’ in the BBC article was indeed unfortunate and anyone trying to make inaction capital out of this is peddling an ideological rather than a rational position.

    So no change there, then.

  5. Chubbs says:

    We have been way too pessimistic about our ability to do without fossil fuels. What the energy modelers are struggling to communicate: fossil fuels are losing and no longer have the economic scale to meet a high demand scenario.

  6. Everett F Sargent says:

    I’d suggest you all stop digging. Which is actually a very good idea, given where FF’s come from.

    FF’s are like candy to a child. So don’t be childish, be childless. Only you and yours can save the future of humanity from humanity..

    I’m changing my screen name to eightpointfiveorbust,

  7. Chubbs,

    What the energy modelers are struggling to communicate: fossil fuels are losing and no longer have the economic scale to meet a high demand scenario.

    Yes, I agree. My issue is more with the communication strategies employed by the energy modellers, than with the message.

  8. Willard says:

    > it’s still a useful worst case scenario

    As far as worst cases are concerned, there are others whose sum must be more likely by statistical fiat.

    Please do not tell ML or Junior.

  9. verytallguy says:

    “Yes, RCP8.5 has become much more unlikely”

    I’m sceptical

    RCP8.5 depends on two things:
    (1) Carbon cycle feedbacks
    (2) future emissions

    on (1) I’m not aware of any fundamental change in understanding over the last few years
    on (2) I think this is fundamentally uncertain. (We could call it a “monster”, or “wicked”, to emphasise this, should we wish to). I see no real shift from fossil fuels to renewables, no change to low carbon infrastructure, no change to a drive towards consumerism, and no change to countries with reserves of gas, oil and coal wanting to exploit these. All of these point to a long term demand for fossil fuels, particularly liquids for transport.

  10. Everett F Sargent says:

    From the BBC …

    “Does this review mean human extinction is less likely from climate change?”

    Such a non sequitur. So, of course, let us all talk about that one. Or wait and see the movie …

    Dumb and Dumber: Part DCLXVI :/

    It continues …

    “it shows that even the limited attempts to cut carbon that the world has adopted to date are having an impact and the worst emissions scenarios are no longer realistic.”

    The worst case scenarios were ALWAYS so-called unrealistic, as in, they always had low p-values. That is why they are called extreme events to begin with in the 1st place. Double D’oh!

    All I see is still more talk and still no real substantive human efforts. So what exactly changed between yesterday and today? Because whatever it is, I want one ginortic bucketful of that Kool-Aid.

    In 2020, hindsight is indeed 20/20. 😉

  11. Eric Steig tweeted that the communication flaw is in a tautology, summarizing as : “We aren’t as likely to produce as much CO2 as we would have if we weren’t moving to alternative energy sources so quickly.”

    The key is in communicating the factors driving this transition. In the 1970’s, it was straightforward to explain the trend toward more efficient energy usage. Today, its partly the same rationale and partly technology advances and partly awareness of CC mitigation.

    But as VeryTallGuy sees “no real shift from fossil fuels to renewables” then this transition has yet to gain a full head of steam.

  12. verytallguy says:

    VeryTallGuy sees “no real shift from fossil fuels to renewables”:

    citation:

  13. BBD says:

    Agree with vtg. Too much big talk and not enough action.

  14. Chubbs says:

    ATTP,

    Can sympathize with your frustration. Weird how these modeling scenarios mean different things to different people. To some they are just numbers. To others they are visions of the future. Some take it a step further and argue the modelers are trying to determine/influence the future. Whatever, all of us are using these results to inform our view of the future. A bit unsettling when you consider the uncertainty – perhaps that is one reason so much emotion is generated.

  15. Everett F Sargent says:

    So, now we have MOVING baselines, because everyone just loves an oxymoron or some such. So now we change both the numerator and denominator? Why? Because it was all just s-o-o-o-o-o-o-o-o-o-o-o much simpler before now and we just can’t have that now can we?

    Anyone up for Three-card Monte?

    “In its full form, Three-card Monte is an example of a classic “short con”[2] in which a shill pretends to conspire with the mark to cheat the dealer, while in fact conspiring with the dealer to cheat the mark. The mark has no chance whatsoever of winning, at any point in the game. In fact, anyone who is observed winning anything in the game can be presumed to be a shill.”

    I know who the shill is, do you?

  16. Everett F Sargent says:

    My EV is bigger than your EV.

    Bigly Yuge.

  17. The Very Reverend Jebediah Hypotenuse says:

    Michael Mann:

    Let me provide some context and caveats about this new commentary. First of all, it is just that–a commentary, not a peer-reviewed scientific article. That must be kept in mind by anyone somehow thinking this overthrows conventional scientific thinking. It doesn’t. It’s basically an opinion piece.

    Meanwhile, not-an-opinion-piece:

  18. “…no real shift from fossil fuels to renewables…”

    And yet we know that investment in renewables, globally, has been between $200 and $300 billion a year for a decade. And the cost has come down, so you get “more” for every dollar. We know this because the warm like to tell us.
    https://www.weforum.org/agenda/2019/09/global-renewable-energy-investment-slowing-down-worry/

    Back to messaging-
    If you insist that the over $2 trillion spent on renewables globally in the last 10 years is “no shift,” then what logical questions flow from that?

  19. ATTP: “Yes, RCP8.5 has become much more unlikely, but it’s still a useful worst case scenario and there are still valid climate modelling reasons for using it. However, it’s also important to recognise that our current trajectory is probably not taking us along an RCP8.5 pathway.

    As already suggested by Gavin, I wonder whether people do not understand the term business as usual scenario. It is the no policy scenario, the climate change is a hoax scenario, the sound from windmills give you cancer scenario, the ice age next week scenario, the I am a better scientist than actual scientists scenario, the heat cannot flow from a cold to a warm object scenario.

    Business as usual is NOT the humanity will do what is economically rational according to some bureaucrats who never noticed WWII, Brexit or Trump scenario.

  20. VeryTallGuy sees “no real shift from fossil fuels to renewables”:
    citation: [graph of primary energy by fuel]

    This is not a fair graph, for all ways to produce energy it uses the amount of energy put in, while for renewable energy it is the energy output. It underestimate the contribution of renewable energy by a factor 2 or 3.

    So we are more realistically around 6% renewable energy and it has a growth rate of 10 to 20%. With 6% adoption we are near the part of the logistic growth curve where is goes really fast, there is a reason fossil fuel companies are panicking.

    (This graph also ignores energy efficiency, which is mostly responsible for the reductions in energy efficiencies and CO2 emissions of EOCD economies up to now.)

  21. Thomas Fuller says:

    Some day, someone who understands business will actually explain to some here what business as usual actually means. It is apparently not today.

  22. TF,
    What about it do you think we don’t understand? Seems pretty straightforward to me. You wouldn’t be confusing “doesn’t agree with me about RCP8.5” and “doesn’t understand what business as usual means”?

  23. agree with BBD and VTG – we are deep in the woods on atmospheric CO2 accumulation with no change in the steady annual upward push at over 2 ppm. This looks like business as usual to me, but the definitional problem for “business as usual” is readily apparent. If we change things around a lot and talk nonstop about the change and increase continues at more than 2 ppm per year, that situation speaks for itself, does it not?

    One other thing that occurs to me as I re-read through the post and comments is that the discussion of 8.5 is a lot like the batter who steps up to the plate with the mantra “don’t strike out, don’t strike out” going through their head. Pretty different from mantra “see the ball, hit the ball.” Maybe we should be focused on discussion of the RCP path that we desire? How are we doing at getting to anything like an RCP 2.6 to 4.5 outcome at 2100? Why shouldn’t we be talking about the pathway that we want to be on instead of arguing about the worst case scenario.

    Also, and finally for now, I don’t think the RCPs are like rail lines where we get on and ride to the station. I think they are just arbitrary lines in the space of possible paths we may see with CO2 accumulation, right? Why not shoot for RCP 3?

    I think this struggle is comparable to WWII. Leaders like Churchill and FDR did not sugarcoat the situation, they were clear that the risks were very high. Churchill said I have nothing to offer but blood, sweat, toil and tears. FDR said the thing to fear was fear itself. Leaders should inspire real action, sacrifice and courage. That may be short on nuance, but it might be long on appropriate action. Be brave, demand and act/work for what you really want.

  24. Thomas Fuller says:

    For your purposes, BAU should be expressed as ‘absent policy changes.’ That phrase has the dual advantages of being both accurate and understandable. It would also obviate the need to distort the meaning of ‘business as usual’ from its actual meaning.

  25. TF,
    Okay, still not sure what your overall point is. I think most people recognise that that is what “business as usual” means. I will add that some define it relative to a fixed time.

  26. Pingback: Eni sta alla sostenibilità come... - II puntata - Ocasapiens - Blog - Repubblica.it

  27. izen says:

    If RCP8.6 is to be considered increasing unlikely can we also agree that RCP2.6 has become even more improbable ?

  28. BBD says:

    Tom

    3K will be a disaster and that’s where we’re headed. All the back-and-forth about BAU and 8.5… misdirection and mouse farts. Irrelevant.

  29. Willard says:

    Why would the creator of a website called 3000 quads try to raise concerns about the meaning of BAU may remain a ClimateBall mystery for a long time.

  30. Chubbs says:

    Izen,

    Yes, there is an irony here. Making the best-case better also improves both the BAU and the worst-case scenarios. Yet all the discussion is on the BAU/worst-case, which in the end of the day, don’t have much effect on anything.

  31. Joshua says:

    > Why would the creator of a website called 3000 quads try to raise concerns about the meaning of BAU may remain a ClimateBall mystery for a long time.

    I think that Tom’s concerns are fairly transparent.

  32. Thomas Fuller says:

    I’m not sure what causes what, but fuzzy terminology and fuzzy thinking seem inextricably linked. Not to mention somewhat a-scientific, at least to this non-scientist.

  33. “Humans will use 3,000 Quads by 2075. If they all come from coal we’re ruined.”

    opening sentence of 3000quads website. His definition of “business as usual,” his opposition to BAU, and the suggestion that there is something other than BAU seem quite clear to me.
    Or is your objection the suggestion that people will use energy in 2075?

  34. Business as Usual in terms of oil production has gone through a transition in the last decade. In most regions of the world, oil production has peaked or plateaued. Only the USA with oil fracking (and Canada less so with their tar sands) has shown a brief respite. However, fracking is just a blip and won’t last more than a few more years.

  35. verytallguy says:

    “This is not a fair graph, for all ways to produce energy it uses the amount of energy put in, while for renewable energy it is the energy output. It underestimate the contribution of renewable energy by a factor 2 or 3.”

    I think you’re half right.

    My condensing boiler has an efficiency of 90ish percent. Output and input are similar for such a system.

    For an electric car, using renewable energy, you need to account for transmission, storage and conversion losses. Much better than ICE, but nowhere near 100%.

    For industrial processes, probably somewhere between the two.

  36. verytallguy says:

    Jeff

    If you insist that the over $2 trillion spent on renewables globally in the last 10 years is “no shift,” then what logical questions flow from that?

    If you omit the word “real” from the quote, and also omit the comparison to the estimated $80 trillion spent on fossil fuels over the last 10 years, are you guilty of sophistry, or carelessness?

    And given that you know full well these sorts of deceptions will not pass under the radar here, can we logically conclude you are trolling?

  37. The The Very Reverend Jebediah Hypotenuse says:


    Why would the creator of a website called 3000 quads try to raise concerns about the meaning of BAU may remain a ClimateBall mystery for a long time.

    Some day, someone who understands ClimateBall will actually explain to Tom Fuller what ClimateBall As Usual actually means. It is apparently not today.

  38. BBD says:

    Or is your objection the suggestion that people will use energy in 2075?

    One objection might be that quibbling about high end FF scenarios when even optimistic assumptions point to 3K by century’s end is misdirection.

  39. BBD says:

    I think you’re half right.

    I’d sort of agree, but the efficiency argument is another quibble, really. Renewables (predominantly scaling W&S) have a very long way to go before they displace FFs as the main source of TPE.

  40. Ben McMillan says:

    Well, for a gas boiler, it is 90% efficient if all works well. But it actually takes energy to extract, compress and transport the gas, too. A heat pump is ~300% efficient.

    Electric cars are about 3-4 times as efficient as petrol in energy terms (again, well-to-wheels, because petrol also needs energy to be extracted, refined and transported).

    The primary energy graph has a nuclear wedge three times as big as the renewables wedge. But in reality, renewables generate as much electricity, and the waste heat from nuclear makes up the rest. Primary energy overstates the importance of fossil fuels and nuclear in the electricity sector by a factor of ~3.

    So, sure, you need renewables to supply most/all of TPE. But the primary energy needed if everything is electrified is at least a factor of two smaller. And hopefully people do obvious stuff like insulate their houses as well. This is not just quibbling: this is the difference between something achievable, and something impossible a’la Mackay (because you run out of land).

    Obviously, we aren’t doing enough; but claiming that we are doing essentially nothing useful seems a bit counterproductive.

  41. mrkenfabian says:

    I tend to swing ambivalently between pessimism and optimism; it is very late and slow but renewables are now the most built new electricity generation and that is a significant consequence of passing a tipping point on price – something most pundits thought would NEVER happen. A petty bit of amusement on my part to think the support grudgingly given to wind and solar probably and ironically included a significant “give em enough rope” element.

    And still pricing of energy options in most places still excludes any of the externalities that the whole energy/emissions/climate condundrum is all about. I suspect wind and solar and storage would win on cost right now in most of the world if the externalities were priced even close to a low order estimate of the future climate costs. And renewable costs have not yet shown signs of bottoming out. It is not all gloom.

  42. miked says:

    If BAU was so easy to define there would never be any argument about it being like or unlike RCP8.5. We would know But it is not defined. I would like to see climate scientists define BAU forcing as a projection of recent times to put an end to the uncertainty. Once done it stays fixed. A baseline. Then we argue if our path is proceeding better or worse than the definition.

    Extrapolating trends of the last 30 years suggests BAU has a forcing between 6 and 8.5 W/m2 by 2100. 6.5 assumes no acceleration but we know CO2 emissions in BAU accelerate 1.5% to 2% per year. So a higher estimate is more reasonable.

    If we use my preferred estimate of 7.5 W/m2 increasing at 0.7 per decade (currently 0.4) then we reach 8.5 just 15 years later. It is hard to escape the fact that BAU is more like RCP8.5 then any other RCP because the end result is the same. The people who place BAU as RCP8.5 are well aware of this.

    Arguing that RCP8.5 burns different fuels so cannot be the same as BAU while ignoring or hiding the fact they have very similar effect is I feel a deliberate deception. I have yet to see any of the complainers mention what forcing they they think BAU equates to. Maybe these people have a very different concept of BAU but if so why don’t they tell us what it is.

    If ZH et al think RCP8.5 is extremely unlikely then this must be good news because it also means that BAU is also extremely unlikely. ZH indicates that trends over the last decade indicate we have changed our ways so 6 W/m2 is more likely now. I.e. we have changed so are not following BAU. I hope he is right but 10 years is a very short time to infer a change in trend. However 6W/m2 is the value expected if forcing increases at constant rate. Oh well at least not accelerating is a change. Isn’t it?

  43. verytallguy says:

    Ben

    “The primary energy graph has a nuclear wedge three times as big as the renewables wedge. But in reality, renewables generate as much electricity, and the waste heat from nuclear makes up the rest. ”

    I think the “primary” from nuclear is defined as electricity, not heat from fission.

    Could be wrong, might have a dig tomorrow.

    I agree we are not doing nothing; I do not agree that anything significant has changed to inform the likelihood of an rcp8.5 tomorrow.

    Re insulation, just received a survey report on moving to passive house standards for our home…

  44. izen says:

    Here is the official view of how much CO2 emissions will fall in the US by 2050.

    https://www.eia.gov/outlooks/aeo/
    “After falling during the first half of the projection period, total U.S. energy-related carbon dioxide emissions resume modest growth in the 2030s, driven largely by increases in energy demand in the transportation and industrial sectors; however, by 2050, they remain 4% lower than 2019 levels.”

  45. Ben McMillan says:

    BP stats review 2019 has (non-hydro) renewable generation 10% less than nuclear in 2018 in gross electricity terms (i.e. ignoring the self-consumption to run pumps etc).

    On RCP8.5, I guess I would say something like ‘although there are promising political commitments and technological developments suggesting we may not follow a RCP8.5 pathway, trends in carbon emissions and energy usage over the last 20 years look broadly consistent with many of the RCPs, including RCP8.5.’

    There certainly seems to be plenty of stuff to burn, if we really feel like it. The supply-siders who look at a straight line in oil production and deduce we are about to run out could be right, but it seems more prudent to assume that we can actually dig up a decent fraction of the remaining oil, gas and coal.

  46. “If you’re going around telling people in other disciplines what they should, or should not, do, you’re probably mostly demonstrating your own ignorance.”

    If only you’d said that last April, toBill Moyers and the other organizers of the Nation Institute conference at the Columbia School of Journalism that demanded the media turn up the rhetorical heat in advance of COP 25.

    https://vvattsupwiththat.blogspot.com/2019/05/for-sixth-extinction-you-need-sixth.html

  47. izen says:

    @-Russel
    “If only you’d said that last April, toBill Moyers and the other organizers of the Nation Institute conference at the Columbia School of Journalism…”

    The organisers of the Nation Institute conference at the Columbia School of Journalism were NOT telling scientists how to do research. They were telling media reporters how to do journalism. The organisers are almost all experienced people within the media journalism field, they were advising their peers about about behaviour in a shared field of experience and expertise.

    That the media, and journalists, will tend to sensationalise any story on any subject is an integral part of the process. But the organisers of the Nation Institute conference at the Columbia School of Journalism were NOT advising their fellow journalists to exaggerate climate stories, they were trying to get the issue of climate to be reported at all. While there may be a small problem with media sensationalism, the big problem has been the paucity of ANY reporting of the science or implications of climate change. Especially with the US. When climate change was mentioned in US media reporting it was most often in the context of what Trump said about it.

    https://sciencepolicy.colorado.edu/icecaps/research/media_coverage/summaries/special_issue_2018.html
    “In the aggregate across US television sources, coverage in 2018 went down 30% compared to 2017. Across global radio sources we at MeCCO have monitored, coverage in 2018 was down 8% from 2017.”

  48. dikranmarsupial says:

    “I’m not sure what causes what, but fuzzy terminology and fuzzy thinking seem inextricably linked.”

    no hubris there then. The problem is that the meaning of BAU has evolved because policy has evolved. It isn’t fuzzy thinking for different people to have different views on what a relatively recent, but still evolving, term means. It used to mean “exploiting fossil fuels to promote growth without meaningful consideration of environmental concerns”. It’s current meaning is not actually all that much different – perhaps ” “exploiting fossil fuels to promote growth while largely only paying lip-service to environmental concerns”. Now some appear to be defining it as extrapolating current economic and political trends forwards.

    All this is fine, a more constructive approach might be to add a footnote to explain what you mean by BAU, or for others to ask what is meant by it and for the definition to be given. Suggesting that others are engaging in fuzzy thinking because they don’t do thinks exactly the way you want them to is not every constructive, but it is just another example of hubris in the public debate on climate change.

  49. izen said:

    “Here is the official view of how much CO2 emissions will fall in the US by 2050.

    https://www.eia.gov/outlooks/aeo/

    The EIA is a faceless arm of the government and is not accountable, requiring no scientific peer-review process before they present their results. This makes it different than NASA and NOAA, who actually have had public faces such as Gavin Schmidt and countless other scientists to defend and publish their findings in scientific journals. Independent energy analysts that have followed bureaucratic organizations such as EIA have frequently wondered why their forecasts for energy usage have always followed the same trends as those for economic growth projected by other bureaucratic agencies such as the Commerce Department.

    Moreover, most people don’t realize that there is really no required accounting of oil production by the USA gov’t. The closest they have is something called the “Railroad Commission of Texas”. At one time a person would have to formally request data from their librarian, but now they have an online presence http://webapps.rrc.state.tx.us/PDQ/generalReportAction.do. The same goes for North Dakota who have a Dept of Mineral Resources https://www.dmr.nd.gov/oilgas/. The USGS provides a list of the state-run accounting organizations https://www.usgs.gov/core-science-systems/nggdp/core-research-center/links-state-well-data.

    So the grass-roots energy analysts are the ones that are providing a counter dose of reality by data-mining from the various information sources. This was not even possible several years ago.

  50. Ben McMillan says:

    “BP stats review 2019 has (non-hydro) renewable generation 10% less than nuclear in 2018 in gross electricity terms (i.e. ignoring the self-consumption to run pumps etc).”

    and then says

    “There certainly seems to be plenty of stuff to burn, if we really feel like it. The supply-siders who look at a straight line in oil production and deduce we are about to run out could be right, but it seems more prudent to assume that we can actually dig up a decent fraction of the remaining oil, gas and coal.”

    So we believe in BP stats review? Many of these oil company reports are rife with references to “barrels of oil equivalent” (boe). This may include natural gas finds and low-grade sludge oil. Corporate reports have a significant amount of deception, and it takes some effort t deconstruct what they are saying. So I’m not sure who these supply-siders that you mention are.

    The world consumes over 30 billion barrels of oil per year and the discoveries being made can’t sustain this pace, even when natural gas is included.

  51. Dave_Geologist says:

    So, in summary (per Nordhaus’ take), we don’t need to worry about BAU admissions because we’re currently taking carbon-reduction steps. So we can stop taking carbon-reduction steps.

    Right. Got it. Oh hang on, I think I see a teensie-weensie flaw.

  52. paulski0 says:

    jeffnsails850,

    Or is your objection the suggestion that people will use energy in 2075?

    Not sure where Willard was going exactly, but the idea that we’re heading for most likely an RCP6/3K warming future is fundamentally dependent on us using a lot less energy than 3000 quads by 2075.

    RCP8.5 scenarios are the only ones that get near 3000 quads.

  53. Chubbs says:

    PP linked Glen Peters thread above where he discusses 3C scenarios. Unfortunately he doesn’t provide information on total energy or non-fossil energy sources. Some factors to note: 1) the 3C scenarios have increasing amounts of CCS starting around 2030; 2) land-use change optimistically trends down starting in 2010 reaching zero around 2050, 3) He doesn’t discuss methane or N2O, which are running above the 3C scenarios. The Nature paper is short on detail. So, until an updated scenario is fully built up, not clear that we can declare 3C = no further climate policy, yet.

  54. paulski0 says:

    Chubbs,

    The 3C BAU idea is based on IEA scenarios and those don’t use much, if any, CCS. In the tweet Glen Peters showed various SSP mitigation scenarios and that they tend to utilise quite a bit of CCS to get down to something like a 3C pathway, though not all do.

    Basically net CO2 emissions can be calculated as:

    netCO2 = total energy demand * carbon intensity of energy – CCS

    The main IEA scenarios primarily reduce netCO2 relative to SSP baselines by assuming lower future energy demand, which means CCS is not necessary. The SSP modeling appears to be less optimistic on our ability to reduce future energy demand so requires CCS to meet certain emissions/forcing targets. My suspicion is that this difference is primarily due to economic growth assumptions, with the IEA assuming significantly slower growth, but I can’t find any info about IEA’s underlying socio-economic assumptions.

  55. Chubbs says:

    PaulS,

    Thanks – so some combination of policy and/or slow growth is needed for 3C.

    I think we can do much better than 3C without damaging our economy. In a technology transition, the ramp to about 5% penetration is slow, then if costs continue to fall, rapid adoption follows. With policy, could happen in the near future for solar/wind or EV. Policy will also be needed for all the other sectors.

  56. Everett F Sargent says:

    “but I can’t find any info about IEA’s underlying socio- assumptions.”

    Someone else posted WEO2019 online recently. So that completes that set. Same standard argument, if this stuff is s-o-o-o-o-o-o-o-o-o bloody important, then stop putting things behind paywalls. Oh and eff the gotta make money counterpoint.

    Like opinions, IEA’s is just one of literally dozens done annually (or semi-annually for the most recent EIA). I don’t really get why one would rely on just one of these so-called energy outlooks. Particularly one that continues to hide behind a paywall :/

  57. I think the “primary” from nuclear is defined as electricity, not heat from fission.

    As far as I know the primary from nuclear is the primary energy, they are boiling water like any other primitive power plant.

  58. Chubbs says:

    I’m OK with giving up on high-coal scenarios. Older, conservative analyses put the cost of carbon at $30-50/ton of CO2 or in the ballpark of $100/tonC. The current market cost of coal in the US is $60/ton. So a rough tally indicates that the economic damage from coal is larger than the current economic value. This is conservative since new climate damage analyses and non-CO2 pollution costs are excluded. Coal’s negative value is only going to increase in the future because CO2 does more damage per pound as the climate warms and renewable competition is improving. No wonder the energy-modelers are so worked up.
    .

  59. The International Energy Agency consistently underestimates wind and solar power. Why?
    https://www.vox.com/2015/10/12/9510879/iea-underestimate-renewables

  60. paulski0 says:

    Chubbs,

    Referring to high-coal scenarios is kind of my pet peeve. It suggests that coal is some independent floating entity which is being pumped into these scenarios for no reason.

    They aren’t high-coal scenarios, they are high-energy scenarios. High coal consumption is simply a necessary consequence of high energy demand growth in context of declining growth of oil and gas supply and inability of renewables to scale up quickly enough. If energy demand is going up and non-coal energy supply is going down, you either have to increase coal supply or you don’t meet that energy demand.

    If our ability to economically extract oil and gas is almost unlimited over the next century, as some now claim, then that could be fed into the same high-energy scenario and there would be less coal consumption. If our future ability to extract oil and gas is even more restrictive then coal consumption will go up even faster in the near future if energy demand is still going up. Indeed there is a large range of future coal consumption pathways across SSP5 runs in different IAMs, largely due to differences in future oil and gas extraction assumptions.

  61. VV asks:

    “The International Energy Agency consistently underestimates wind and solar power. Why?
    https://www.vox.com/2015/10/12/9510879/iea-underestimate-renewables

    That’s the logical complement to why their fossil fuel projections are overly optimistic. If they think that total energy requirements will be met by FF, then they can cut back on their estimates for renewables (i.e. the sum total of the two remaining somewhat constant).

    The other explanations by David Roberts are also valid.

  62. izen says:

    @-WHUT
    “The EIA is a faceless arm of the government and is not accountable, requiring no scientific peer-review process before they present their results.”

    I am aware that the EIA has only a tenuous relationship to the material facts about fossil fuel reserves, costs and extraction processes.
    As a result of regulatory capture it best resembles the expectations and requirements of the primary financial interests in the production and use of energy from fossil fuels and other sources. These projections reflect the policy choices preferred by the industry much more than any outcome derived from the actual logistics of extraction or production.

    Looking at the detail, it depicts a continuing steep decline in coal use for electric power generation, with the slack mostly taken up by gas with a little renewable thrown in.
    Where it projects a small increase in fossil fuel emissions is in the transport and industrial sector.
    I think this represents a deep scepticism about electric vehicles replacing liquid hydrocarbons within the 2050 time frame, and a continuing use of fossil fuels in the construction industry, especially with the smelting or iron ore and the production of steel, along with the making of concrete.

    This does not indicate that renewable or low carbon alternatives are unable to replace fossil fuels in these industrial and transport sectors, but that the main players in the businesses involved have no expectation that there will be any significant policy choices, (or technological advances), that would motivate these changes.
    Given the degree of regulatory capture in the US and most other industrial advanced nations this may be a self-fulfilling prophecy.
    The inmates have taken over the asylum.

  63. Willard says:

    > His definition of “business as usual,” his opposition to BAU, and the suggestion that there is something other than BAU seem quite clear to me.

    A quote might be nice, JeffN.

    ***

    > Not sure where Willard was going exactly, but the idea that we’re heading for most likely an RCP6/3K warming future is fundamentally dependent on us using a lot less energy than 3000 quads by 2075.

    Exactly where I was going, PaulS.

    Therefore our luckwarm linguist has no qualms about using catastrophism when it suits him.

    That JeffN could only think about a strawman is par for the ClimateBall course.

  64. Chubbs says:

    PaulS,

    Agree with your point, there is a lot of cherry-picking when these scenarios are discussed. Sure coal, solar, wind have worked in our favor but: nuclear, land-use, BECCS, methane and others have not. Useful to compare the scenarios at equal energy consumption levels. Unless something drastic happens, we will reach every cumulative energy consumption level in each scenario at some point.

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