The impact of climate change, and the cost of climate policies

There’s been a reasonable amount of discussion about Bjorn Lomborg’s fairly recent paper [w]elfare in the 21st century: Increasing development, reducing inequality, the impact of climate change, and the cost of climate policies. A key part of the paper is the claim that

Climate-economic research shows that the total cost from untreated climate change is negative but moderate, likely equivalent to a 3.6% reduction in total GDP.

The claim above is based on the figure on the right, which shows damage functions for various Integrated Assessment Models (IAMs). The claim above is based on estimates for the damage at ~4oC of warming, but plotting these out to 8oC illustrates, in my view, an issue with these damage estimates.

Suggesting that the impact of 8oC of warming would be ~10%, or less, seems so nonsensical that it’s hard to know where these estimates have any validity. There have also been numerous critiques of these damage functions. There’s Steve Keen’s rather blunt critique, but there also a paper by Diaz & Moore that synthesizes published damage function critiques.

Of course, I do realise that if you want to do some kind of economic modelling to assess the impact of climate change and to potentially inform policy-making, you do need something. However, given the simplicity of these damage functions, I do think one should be cautious of making strong, definitive, claims about the economic impact of climate change.

What’s more, if you look at William Nordhaus’s recent paper, you find that the damage, as a fraction of output, is indeed around 4% for the reference scenario, but with a range from close to 0, to about 12%. So, it has a non-negligible chance of being quite large enough to not be reasonable described as moderate.

Lomborg’s paper goes on to say:

The popular 2°C target, in contrast, is unrealistic and would leave the world more than $250 trillion worse off.

However, if you scroll down the paper, you discover that this devastating (and unrealistic) policy would cost 5.4% of future global GDP. So, the economic impact of ~4oC of warming would be moderate at ~4% (but, potentially, >10%) of global GDP but trying to limit warming to 2oC would be devastating at 5.4% of global GDP.

Also, the reference scenario for these estimates is one that is expected to lead to 4 ± 1oC of warming. Anyone who’s been following the climate debate should be aware that there’s been a lot of recent discussion about this. There are strong indications that our current policy is taking us towards a 3 ± 1oC world. Therefore, the reference scenario used in Lomborg’s paper almost certainly makes it seem more challenging/costly to limit warming to 2oC than may now be the case.

I should probably wrap this up. I think that making strong claims about the economic impact of climate change is sub-optimal, especially given the assumptions that are needed in order to develop damage functions (we haven’t actually experienced 4oC of global warming). Also, given that climate change is essentially irreversible on human timescales, we may still want to avoid ~4oC of warming, even if there are indications that the economic impact may be moderate. Also, even if the cost of limiting warming to 2oC is greater than the economic impact of 4oC, maybe this is a cost worth bearing, especially if we’ve already made inroads that this analysis has ignored.

Links:

Welfare in the 21st century: Increasing development, reducing inequality, the impact of climate change, and the cost of climate policies, Bjorn Lomborg’s July 2020 paper.
The appallingly bad neoclassical economics of climate change, Steve Keen’s critique of IAM damage functions.
Quantifying the economic risks of climate change, Diaz & Moore (2017).
Projections and Uncertainties About Climate Change in an Era of Minimal Climate Policies, William Nordhaus’s 2016 paper.
A 3C World Is Now “Business as Usual”, article by Zeke Hausfather and Justin Ritchie.

This entry was posted in Uncategorized. Bookmark the permalink.

68 Responses to The impact of climate change, and the cost of climate policies

  1. Everett F Sargent says:

    But the IPCC AR6 used IAM’s to generate their SSP’s. A-I-E-E-E-E-E-E-E!!! Is that one on our CBB card?

    Oh and if you are willing to watch an extremely bad science fiction movie, I would suggest The Midnight Sky, as it ranks right up there with The Day After Tomorrow and 2012.

  2. Eventual_Horizon says:

    I’m curious if this “degree by degree explanation of what will happen when the earth warms” that gets passed around sometimes has ever received any commentary from the scientific community. http://globalwarming.berrens.nl/globalwarming.htm

  3. MarkR says:

    Lol 5% of GDP at 8 C global warming? I’ll take what they’re smoking, snorting, and injecting.

    That’s like seeing a medical guide with a fever of 45 C labelled as “minor annoyance”.

  4. BBD says:

    If Lomborg is peddling it, it’s on a scale between misleading and wrong.

  5. Just to limit myself to two points (for now).

    1. A large part of what’s missing from the Lomborg (and others’) comparison between the “foregone GDP” “cost” of mitigating to 2°C versus the “cost” of incurring damages not avoided between 2.0°C and 4.0°C (or more) (which you partly allude to): The damages figure is an “expected value(range)”, but there is a non-zero risk that the damage could be catastrophically higher (via surprises in TCRE/ECS, unmodelled damages to agriculture, etc.). An mitigation is a form of insurance against these low-probability risks.

    So the willingness, or breakeven point, for 2°C mitigation expenditure is not just a simple CBA exercise where “if less than expected damages, proceed, else don’t”. Because there is both an insurance premium and “optionality” aspect to mitigation spending.

    We don’t accept fire insurance expenses based strictly on whether they are less than the expected value of fire damages to the structure over the pertinent period, etc.

    The premiums are (almost) always far more expensive.

    And, of course, with the planet, we do not collectively get to spread our risk across multiple outcomes, like we do with multiple houses.

    Anyway, just one of many problems with Lomborg-like framing/ranking.

    2. Conversely (and again, you allude to this), the criticisms of Lomborg for damage estimates at the tails seems to obscure (some of) our ability to think rationally about plausible damages at lower temperatures.

    8°C would require roughly 4,000 GtCO₂ of anthropogenic cumulative carbon emissions. We’re at about 633 GtCO₂ now and emitting 11 GtCO₂ (and maybe plateauing?). So, even if economic damages at 8°C were universally stipulated to be catastrophic or even (near) total, we are talking about a scenario that is probably not policy relevant.

    And there, I think the fixation on damage function at 8°C, and then sort of extrapolating back to, say, 4°C, and inferring, “therefore still catastrophic!” is unhelpful and unpersuasive.

    I mean, we have already incurred 1.2°C warming. What global GDP would we presently be at – counterfactually – if the temperature had remained unchanged? I suspect the delta to actual present GDP is uncomfortably close to zero. And we obviously increased absolute GDP by a staggering amount while experiencing that 1.2°C increase. My point being that some of the “crazy” research Lomborg is citing is not so clearly unfounded as some want to dismiss it as.

    We, of course, do not know the damages or growth for the *next* 1.0°C, etc. And yes, obvious Atlantic cod, etc., tells us to be extremely cautious about “steady as she goes”.

    But one thing that PAGE, DICE, FUND, Marshall Burke et al, Diaz and Moore, etc. have that many of the critics don’t: testable hypothesis and published models, assumptions and projections…

  6. Rust,

    And there, I think the fixation on damage function at 8°C, and then sort of extrapolating back to, say, 4°C, and inferring, “therefore still catastrophic!” is unhelpful and unpersuasive.

    My point about 8C is simply that these damage functions will provide an estimate of the economic impact of 8C of warming, but it seems clearly nonsensical. So, clearly, there is some level of warming, above which these estimates are clearly wrong. Consequently, for what levels of warming do they provide reasonable estimates, and why? I’m also not suggesting that this means they should not be used, but I do think they should be used with caution.

  7. b fagan says:

    Thanks for the link to the Keene paper. I don’t go often into the land of the economists, and now I remember why. When it mentions the faulty assumption that what happens indoors isn’t affected by the outside climate, I thought instantly of the worldwide disruption in the computer industry because of floods in Thailand. When divers have to enter your factory, you are not producing disk drives in that factory for a while, no matter that the roof and walls are intact.
    https://spectrum.ieee.org/computing/hardware/the-lessons-of-thailands-flood

    From Lomborg’s abstract, is seems he’s never going to stop playing exactly the same tune:
    “The most effective climate policy is increasing investment in green R&D to make future decarbonization much cheaper. […] The current climate discourse leads to wasteful climate policies, diverting attention and funds from more effective ways to improve the world. This article will outline how to establish a rational climate policy in the context of many other, competing global issues.”

    Kick the can down the road with pennies for more R&D (not really D, just inexpensive R), so we eventually decarbonize for free; pretend only the most “alarmist” changes are the ones scientists and policymakers know need attention; trot out his trademark Lomborg McGuffin, the “competing global issues”.

    Never mind that switching rapidly away from carbon fuels will free up water resources (issue), will reduce illness and deaths from pollution (issue), will also reduce the future acceleration of damage to the coastal and riverside infrastructure everywhere (issue) that’s damage level is based on emissions and energy choices made over the next few decades.

  8. Well, even accepting these bizarre numbers, if the problem and the solution are about the same cost, but you can compute the price of the solution reasonably well, while it is hard to compute the costs of the problem, then it seems a good insurance deal to implement the solution.

    Add to this that the low costs of the problem seems unphysical and have much higher risks on the high costs side, as well as that solving the problem reduces damages to human heritage and the biodiversity that took billions of years to evolve.

    No brainer, even accepting these bizarre numbers.

  9. Chubbs says:

    “increasing investment in green R&D” LOL, what a joke. Relatively modest subsidies for the deployment of solar, wind, batteries, EV, etc. has given us technologies that are very competitive with fossil fuels.

    Its too late for “green R&D” alone to avoid significant climate impacts. No, we have to go rely on available or soon to be available technologies, the ones that are already beating fossil fuels in the marketplace, the ones that energy economic models completely missed.

  10. David B Benson says:

    Here is another philosopher on probability:
    View at Medium.com
    with conclusions similar to the Stanford Encyclopedia of Philosophy article; but not identical.

  11. Dave_Geologist says:

    I think that making strong claims about the economic impact of climate change is sub-optimal

    The problem is that for many, BL included, it’s super-optimal.

  12. Dave_Geologist says:

    Missed the Merry Christmas page so I hope everyone had a good one (considering).

    I tend to think of Lomborg’s spurious certainty as the evil twin to “we don’t know everything, therefore we know nothing”.

    Just listened to Jeremy Farrar’s piece on the BBC Today Programme about uncertainty.

    My expectation was that it would devolve into the layperson’s view of uncertainty vs. the scientist’s* view: “we know nothing” vs. “the answer lies between here and there, probably round about this value a bit to the left** of the middle”. It started to plan with the interviewer’s “we’re having a stab at it, but we’re not sure” (on Covid guidance to government), but it was mostly about policy advice under uncertainty and how that changes as certainty improves.

    I recall arguments in the spring that giving a factor of 10 or 100 range on outcomes made advice not useful. But if I was a Minister I’d respond very differently to “between 1 and 100 deaths if we do nothing, probably around 5”; “between 1000 and 100,000 deaths if we do nothing, probably around 5,000”; and “between 100,000 and 5,000,000 deaths if we do nothing, probably around 500,000”. Similarly with GDP hit: even if we accept the silly 4%, “between 2% and 50% hit if we do nothing, probably around 4%” would at least prompt the question: “what can we do to rule out that horrendous fat tail?”.

    Of course the “tell” in the paper is the claim that the economic impact of ~4°C of warming would be moderate, but expending 5.4% of global GDP to limit warming to 2°C would be devastating. Even Lomborg would surely admit that 4% and 5.4% are so close and the uncertainty range so large that they’re functionally equivalent. The choice of adjectives alone tells you he’s not dealing a straight deck.

    * In the oil and gas industry we tended to separate risk from uncertainty because we were often dealing with discrete outcomes: discovery or dry hole (risk) and reserves range if a discovery (uncertainty); well under control or blowout (risk) and range of outcomes from a blowout (uncertainty), with the first expressed as a percentage and the second as a range. But the first is just uncertainty between discrete outcomes: in the Covid case that might be no vaccine vs. protective vaccine vs. herd-immunity vaccine; in the IAM case it might be with or without commercial fusion or pocket fission power, or with or without CCS, or with or without a resource or territorial war going nuclear.

    ** Since many the impact factors are likely to be multiplicative not additive, and there are bound to be very non-linear fat tail impacts like mass starvation, refugee movements and so on, I’d fit a lognormal distribution rather than normal if I had to choose, and would be very suspicious of any IAMs which output normal distributions of economic damage.

  13. Nathan says:

    Also PIK recently went through Nordhaus DICE model and re-ran it with up to date data and found 2 degrees was the sweet spot, not 3.5 degrees.

    https://www.pik-potsdam.de/en/news/latest-news/an-economic-case-for-the-un-climate-targets-early-and-strong-climate-action-pays-off

    https://www.nature.com/articles/s41558-020-0833-x

    Haven’t read the paper.

    It appears to me that economics is used to make predictions (projections?) about the future but is held to less account that other modelling… Do they do calibration runs? Do they look at how successful their models are?

  14. Ben McMillan says:

    Imagine you tried to find an optimal way to respond to the current pandemic using an IAM to optimise world GDP.

    Not only would this be likely to fail on its own terms, but it isn’t even the right objective. I think Koomey is arguing along the right lines that a cost-benefit analysis is just the wrong tool.

    Trying to measure the kinds of damage climate change is likely to cause in GDP terms locks you in to paradigm where money is real, and everything else is secondary; where agriculture is unimportant, because it is a small slice of GDP. The poorest billion people only represent a tiny proportion of GDP.

    It basically end up being “what’s good for rich people’s bank accounts” with a tiny side-serving of “you’ll have to wear a space-suit to do farming”.

  15. Ben McMillan says:

    Also, people have attempted verifying IAMs by hindcasting the 20th C:
    https://www.pnas.org/content/113/31/8675

    It doesn’t work that well, obviously. The parametric and structural uncertainties are huge. Early studies thought that mitigation would cost ~hundreds of dollars per tonne, but it looks like a lot of the mitigation is now negative cost (including health co-benefits).

    There are a bunch of calibration studies on shorter timescales that look a bit more reasonable, but predicting the future of human civilisation is a bit of a tough problem. Makes climate look like a piece of cake.

    The uncertainties a big part of why more recent IAM results are far different (generally much lower ‘optimal’ emissions that the early DICE studies); accounting for uncertainties and risk-aversion tends to push you toward a more conservative approach.

  16. Chubbs says:

    The free-market can solve all of the worlds problems; but, only if we accept a degraded climate (and planet). What a bizarre philosophy.

  17. Jeffh says:

    Lomborg is like a horrible rash that won’t go away. His sophomoric calculations perpetually exclude the link between the material and natural economies. In other words, he ignores the already enormous impact that climate warming and extremes are having on our ecological life support systems. By failing to factor this into their little econometric models, Lomborg, Nordhaus and optimists like Steven Pinker are suggesting that mankind is exempt from natural laws. Given that none of them have even a basic grounding in environmental science, it takes considerable hubris for them to make such underwhelming estimates of costs associated with warming of 2 degrees or more. A recent paper by myself and colleagues in Global Change Biology argues that climate extremes alone (more intense heat waves, floods, droughts and attendant processes like fire) are going to lead to the breakdown of food webs (we focus on insects but this applies across invertebrate and vertebrate taxa given their interconnectedness) and trophic interactions that underpin the functioning of ecosystems. Ecosystems and biomes, in turn, generate an array of ecological services upon which our industrial civilization depends. Longer term incipient warming, along with climatic extremes, are already hammering biodiversity. The implications of even 2 degree warming in the next several decades are terrifying to contemplate for those who know what they are writing or talking about. Lomborg does not qualify.

    By now I am both exhaused and fed up with those like Lomborg who sweep ecology under the rug when it comes to predicting the societal costs of climate warming. By-and-large it is important to note that environmental scientists and systems and population ecologists give everything Lomborg writes a pass. The only reason that he is still considered relevant is because his views are promoted by powerful, vested interests and the neoliberal elites who see mitigation as a threat to the way they do business. So they give him a veritable megaphone to keep on muddying the waters. It is both disingeuous and dangerous,

  18. Jeff,

    By now I am both exhaused and fed up with those like Lomborg who sweep ecology under the rug when it comes to predicting the societal costs of climate warming.

    Yes, I have the same problem. There seem to be some who continually repear the same arguments, don’t engage with their critics, and – as you say – continue to have a platform because what they’re saying appeals to powerful groups with vested interests.

  19. Willard says:

    Perhaps one day we’ll get there:

    Scientific evidence suggests that economic activity is threatening global biodiversity in ways that could severely degrade nature’s flow of ecosystem services. Yet, there is relatively little work in economics that addresses biodiversity loss. Some economists have called for better integration of economic and ecological models to address biodiversity and the attendant ecosystem services. Current integrated approaches in economics are discussed, and they take in ecosystem services, ecosystem externalities, and substantial ecological modeling. Much of the modeling uses Lotka-Volterra equations, which are standard in ecology, although there is concern that the equations lack the microfoundations of plant and animal behavior. An alternative approach is to admit microbehavior using economic optimization techniques that build adaptive ecological systems. However, much more effort is needed to assess whether admitting more ecological detail into economic models will be fruitful.

    https://www.annualreviews.org/doi/10.1146/annurev.resource.050708.144113

    Meanwhile, it might be best to look at the insurers’ homeworks, e.g.:

    Regarding agriculture in particular, the provision of effective insurance is also a way to facilitate a more productive agricultural sector. Intensifying rainfall and heatwaves are making crop yields more erratic, emphasizing the need for insurance and the role of impact underwriting.
    Figure 12 illustrates the results from a multi-model simulation study for different underlying climate change scenarios (analyzing various scenarios in various different models). The red areas indicate a significant (more than 5%) decrease and the blue areas a significant increase in the respective crop yield, for the indicated share (>50% or >75%) of the underlying model runs, given a 2.5°C increase in global mean temperature. Still, with rising average temperature it is predicted that also the variance of temperature and precipitation will be impacted, including an increase in the frequency and duration of extreme events. When evaluating the effect of climate change on crop yields it is crucial to account not only for the mean effects of rising temperature but also for crop yield variance. Figure 13 illustrates expected significant (larger 5%) increases (blue) and decreases (red) in variance, for the indicated share (>50% or >75%) of the simulation runs, given a 2.5°C increase in global mean temperature. While the losses in average yields are particularly affecting developing and emerging countries, increases in yield variability are expected in much of the Northern Hemisphere, particularly in North America, Central Asia, and China.

    https://www.eulerhermes.com/en_global/news-insights/economic-insights/Impact-underwriting-sustainable-insurance-as-an-opportunity-for-society-and-business.html

  20. Much of what contributes to GDP in a too-warm future might consist of repairs and replacements to structures and ecosystems damaged by an increasingly unstable climate.

    Limiting increases in GAT to 2C was a consensus scientific agreement. Adding the ‘stretch goal’ of 1.5C was a political goal motivated by a common-sense desire to give us a safety margin.

    Setting up a 3.5C target seems a mistake, and I speak as one who has been a constant defender of the Bjorn for more than a decade.

    Aim for 1.5C, settle for 2C, spend on mitigation and pre-adaptation–and mandate CO2 friendly cement and the most efficient jet engines we can develop.

  21. Chubbs says:

    One wonders if the econ models use technology learning curves and if so have they been updated.

    https://ourworldindata.org/grapher/solar-pv-prices-vs-cumulative-capacity

  22. Pingback: Versione 2.0 - Ocasapiens - Blog - Repubblica.it

  23. It appears to me that economics is used to make predictions (projections?) about the future but is held to less account that other modelling…

    An economics professor in his introductory public talk told us that the official economic prediction groups had never ever predicted a recession right.

    In one way I feel for them. If they predict it, they make is happen, but it is still an abysmal track record.

  24. Nathan says:

    Ben McMillan
    Thanks, that’s not so comforting.
    I guess when your model has no fundamental basis (like physics in other models) it is extremely difficult to make long term predictions or projections; because the past doesn’t really inform the future as with physical things.However, they just make the model as if it does.
    As they say: “An important reason why the model performs poorly is that the post-World War Two boost in productivity growth is not presaged in the training data at 1920. This finding is indicative of the difficulty of predicting long-run technological developments.”

    But to be honest the results don’t look awful

  25. Chubbs says:

    Skimmed report, very difficult to understand what the numbers are based on or whether there is any consistency in the calculation method. Has the appearance of an advocacy piece where evidence is cherry-picked to support a narrative. Certainly the numbers for renewables look biased/outdated/made up.

    The narrative is simple and I could see where it could be effective: take your pick its either climate change or other problems. Progress/innovation is a conserved property, squander it in one area and live with the consequences. Of course, reality doesn’t fit the narrative; if we aren’t willing to tackle problems, they fester and infect into other areas.

  26. paulski0 says:

    So, the economic impact of ~4oC of warming would be moderate at ~4% (but, potentially, >10%) of global GDP but trying to limit warming to 2oC would be devastating at 5.4% of global GDP.

    Yep, it has to come down to playing with language because, for all their faults, IAMs and these equilibrium damage functions do support substantial strengthening of current climate policies.

    Not sure about your criticism of the reference scenario. All that really matters is that the reference scenario used is consistent for warming damage and policy cost calculations. It’s not necessarily relevant what current policy warming implications are now if the costs of those policies are not already factored in as part of the reference GDP forecast.

    Also, about current policy leading to 3C, I’ve looked into all these estimates and they’re all biased low, for essentially the same reason: Their extrapolations to 2100 are based on scenarios which include substantial policy strengthening even though they’re claiming to represent a future with policy held fixed at current levels.

  27. Paul,

    Not sure about your criticism of the reference scenario. All that really matters is that the reference scenario used is consistent for warming damage and policy cost calculations.

    Yes, good point. If we just want to compare costs then it’s probably not that relevant (although, it’s not obvious to me that it’s completely irrelevant – presumably it’s possible for the damage estimates and policy costs to scale with \Delta T in such a way that the reference scenario does influence the comparison).

    The point I was making, though, was that by using a reference scenario that leads to 4 +- 1C of warming by 2100, the policy costs will seem higher than if the scenario was one that would lead to 3 +- 1C of warming (as is now regarded as a more reasonable baseline).

  28. paulski0 says:

    ATTP,

    Sure, getting from 3C to 2C would require less policy change than 4C to 2C. But then the difference in damages between 3C and 2C is only 1 percentage point according to the DICE function, versus 3 percentage points for 4C and 2C.

  29. Paul,
    Okay, yes, I see what you mean.

  30. paulski0 says:

    Tom,

    Setting up a 3.5C target seems a mistake, and I speak as one who has been a constant defender of the Bjorn for more than a decade.

    The 3.5C target appears to be based on the “optimal” result in a 2017 Nordhaus paper. However, as covered on this site a while ago, the 3.5C calculation was just plain wrong. Nordhaus’ model only calculates CO2 emissions internally so takes non-CO2 forcings from other sources. In this case he used RCP8.5 as input, but more importantly included no facility for modifying non-CO2 emissions through policy. So, his optimal scenario has fossil fuel CO2 emissions declining to just above 10 GtCO2 by 2100 but somehow fossil fuel methane emissions are implicitly at massive record highs.

    Nordhaus’ optimal is really a classic RCP4.5, producing 2.5-3C 2100 warming.

  31. Willard says:

    That tweet I posted elsewhere might also belong to this thread:

    All modellers have skeletons of spherical cows in their closets:

    The phrase comes from a joke that spoofs the simplifying assumptions that are sometimes used in theoretical physics.

    Milk production at a dairy farm was low, so the farmer wrote to the local university, asking for help from academia. A multidisciplinary team of professors was assembled, headed by a theoretical physicist, and two weeks of intensive on-site investigation took place. The scholars then returned to the university, notebooks crammed with data, where the task of writing the report was left to the team leader. Shortly thereafter the physicist returned to the farm, saying to the farmer, “I have the solution, but it works only in the case of spherical cows in a vacuum”.

    It is told in many variants, including a joke about a physicist who said he could predict the winner of any race provided it involved spherical horses moving through a vacuum. A 1973 letter to the editor in the journal Science describes a physicist whose solution to a poultry farm’s egg-production problems began with “Postulate a spherical chicken …”.

    https://en.wikipedia.org/wiki/Spherical_cow

    I would still take modulz, however stoopid, over CEOs with megaphones, e.g.:

  32. Willard says:

    Nathan Tetlaw linked to a newsie about a recent paper:

    “We essentially unpacked Nordhaus’ model, checked it thoroughly, and made some key updates based on most recent findings from the latest climate science and economic analysis,” Martin Hänsel, lead author and researcher at the Potsdam Institute for Climate Impact Research (PIK), explains. “We found that results from the updated version are in fact in good agreement with the Paris 2°C limit for global warming.” The updates include an updated carbon cycle model, a recalibration of the temperature model, an adjustment of the damage function, and new evidence on the normative assumptions in the model’s social discount rate based on a broad range of expert recommendations. This is complemented by revised assumptions regarding non-CO2 greenhouse gas emissions, negative emission technologies, and constraints on the feasible speed of decarbonisation.

    […]

    The changes made to the model, including setting the social discount rate more in favour of future generations’ wellbeing, has further ramifications: It produces a higher price on carbon. The median of all model runs in the updated DICE model yields a CO2 price of around USD 100 per ton of carbon in 2020. CO2 prices resulting from the majority of expert views on social discounting are, with few exceptions, higher than what is being implemented in most sectors even in the most ambitious regions of the world.

    https://www.pik-potsdam.de/en/news/latest-news/an-economic-case-for-the-un-climate-targets-early-and-strong-climate-action-pays-off

  33. David B Benson says:

    Good find, Willard. Thanks.

  34. gwws says:

    The Lomborg paper is disturbing. The weak point is that everything hinges on the time horizon of 2100. If I were sure that we (humans, live beings, whatever) would cease to exist in the year AD 2100 then I would certainly buy his argument. But Lomborg seems to say: “No need for an expensive solution now. We will have more money in 2100 and the solution might well be cheaper then.” It sound to me like a home owner with a leaking roof saying: “It is cheaper to buy a big pail.”

  35. It sound to me like a home owner with a leaking roof saying: “It is cheaper to buy a big pail.”

    No. this is the preferred solution …

    After Delta rips tarps off homes of Laura victims, Operation Blue Roof to restart in Louisiana
    https://www.theadvocate.com/baton_rouge/news/weather_traffic/article_06975fcc-0bf7-11eb-a17f-ab8d6ba0347c.html

  36. Willard says:

    Nathan’s tweet follows that tweet, David:

    The whole thread is good.

  37. izen says:

    I don’t think Lomborg’s paper, or any of his writings, are designed or intended to convince anyone who isn’t already harbouring a belief in the irrelevance of climate change.
    Or at the very least, its subservience to other more ‘pressing’ problems.

    While he may appeal to those willing to continue to reject climate change, he may be right in identifying other problems as dominating the obstruction to acting to reduce emissions. I see little chance for emissions to be reduced while large fossil fuel extractors and providers still dominate the economics of various Nations.
    There seems to be a direct correlation between the size of fossil fuel producers and the degree of rejection that is prevalent within any society. Correlation does not represent causation, but it does sit there waving in a very significant manner.

  38. anoilman says:

    Izen: Lomborg has a Phd in manipulating how people vote. Other than that, he’s paid to say what he says.
    https://en.wikipedia.org/wiki/Bj%C3%B8rn_Lomborg#Career

    John Mashey summed it up nicely here.
    https://www.desmogblog.com/2015/07/21/bjorn-lomborg-brings-profit-protective-policies-back-to-denmark

    The trick with Lomborg is not to get caught up in his machiavellian ploys.

  39. izen says:

    @-TF2

    Your link goes to an extended critique of an article that overstates the case for societal collapse.
    I fail to see how this refutes any criticism of Lomborg. The fact that a report takes all the worst possibilities of climate change and extrapolates to a disaster for human civilisation does not seem like a cogent response to the Lomborg nonsense.

    I would also note that many of the criticisms of the article state that the authors have merely overstated the timing of the effects, not the certainty of them happening if emissions continue. Sea level rise is a real problem for human society, although it is unlikely to be catastrophic on a 30 year timescale, it will be on an eighty year one. With no let-up in the continuing rise after that point.

    Obviously this has little implication for anybody alive now, and less for any business institution, but it will be a significant problem of adaption for the next few generations.
    Or a trigger for large scale migration, disruption of civilisations and agricultural collapse.

  40. Willard says:

    > I fail to see how this refutes any criticism of Lomborg.

    It doesn’t. Our peddler has returned to “but CAGW.”

    Drive-by done.

  41. [Playing the Ref. – W]

  42. The City of Cambridge is wishing the denialati a happy new year with public notices warning of climate change from burning ethanol:

    https://vvattsupwiththat.blogspot.com/2020/12/puritans-display-holiday-spirit-with.html

  43. Pingback: 2020: A year in review | …and Then There's Physics

  44. Susan Anderson says:

    Lomborg (and his enablers, dupes, and promoters) makes good money doing what he does. Look no further for a reason it goes on. “What’s in it for me” is out in the open, considered to be the ideal. See the success doctrine for more blatant examples, like Paula White and Joel Osteen.

  45. Ben McMillan says:

    Feel more and more like these economic models have no predictive power or planning utility.

    At what point do you say that they are ‘not fit for purpose’? The estimates of costs and benefits have varied so much that the range of answers has gone from “do almost nothing at all” to “stay under 1.5C” which is basically maximal response. For Ozone-depleting gases these approaches were horribly wrong too.

    It isn’t as if cost-benefit approach is the only way to approach this: we could just throw away the climate economics, and just take an engineering-style risk management approach. Or a military-style sails-on-the-horizon approach. Cost-benefit is not the normal way of making these big decisions. We certainly didn’t do it for Covid.

    Take BEVs: IAMs have these mostly as around $5000 more expensive than ICEs till hell freezes over. But seems clearly wrong:

    Since wind+solar are now lower cost than the fossil alternative, and heat pumps for low temperature heat look cheaper than the alternative, a lot of the carbon-reduction over what people thought business-as-usual would look like in AD2000 is going to be negative cost.

  46. Mr. McMillan speaks cogently about the potential for technology to affect CBAs, a point I have tried to make but got lost in the climate scuffles. However, Mr. McMillan, you will need to factor in that cost reductions don’t automatically lead to price reductions, as profit is a compelling motive to keep prices high. The way around that is to encourage new and disruptive entrants into market subsectors.

    New competitors will help keep the market honest.

  47. “Take BEVs: IAMs have these mostly as around $5000 more expensive than ICEs till hell freezes over. But seems clearly wrong … ”

    BEVs = battery electric vehicles

    Then suggest a more equitable BEV offset wrt time. Stop complaining about their relative costs as current comparisons are above that differential afaik.

    I consider myself to be so-called ‘poor’ and the ‘poors’ only ever look at the total up front cost of purchase and never look at the ROI over the vehicles lifetime, particularly if those ROI’s are not real $$$ in their bottom line pockets. I can get a brand new IC4 for ~$15KUS while an BEV is extremely hard to find below ~30KUS. Also buying brand new is not the best cost investment or ROI versus buying used. Finally almost all BEV’s appear to be rather large and expensive from the big three US automakers (SUV’s and trucks that can carry bigger battery packs and have way higher profit margins).

    In my particular case, I have a 1996 Mazda 626 I4 (now with a one time antique plate which is good forever (no more future car tag fees)) which I purchased in 2009 for $2KUS and have had repairs way below $1K to date. It can get 42 MPG highway, if you are actually willing to drive 55 or less (sweet spot is usually in the nid-40’s for IC’s). Oh and I drive somewhat less then 30 gallons of gas annually. That is the best that us ‘poors’ can get away with at this point in time

    In closing, perhaps you should consider the household incomes of all people and perhaps you might see that there is a rather large fraction that see BEV’s as maybe a 3rd (or 4th) option for the foreseeable future.

    Oh and but poors.

  48. John Hartz says:

    Speaking of BEVs and their costs (capital & operating) in comparison to conventional ICE and hybrid vehicles,,.

    Electric Cars Are Better for the Planet – and Often Your Budget, Too by Veronica Penney, Climate & Environment, New York Times, Jan 15, 2021

  49. Ben McMillan says:

    EFS: Well, the problem of existing fossil tech sticking around for a decade or two is a real one. I’ve got a vehicle almost as old as yours sitting in front of my house, not doing many miles a year. It’s now old enough that there are lots of places nearby (e.g London, and bits of France) you can’t drive it.

    Not that common though: the less-well-off people round here are driving 10ish-year-old hatchbacks. Most of the cars doing a lot of miles are quite a bit newer though. Real poor people (esp. in developing world) don’t have cars at all.

    But anyway, purchase cost-parity isn’t for another few years, and poorer people won’t be buying used BEVs for quite some time.

    This is a transition that will take a while, even when the cleaner tech is cheaper.

  50. John Hartz sez ..

    They forgot to add in annual insurance premiums and annual car tags (both of which are based primarily on the retail price of a new vehicle + its actual age). There are also other hidden costs (e. g. if the BEV does not get 100% of its energy from renewables. the initial carbon footprint of building the BEV with anything less then 100% renewables, which themselves must be built from 100% renewables, and whatever else I can’t think of for the moment).

    My average annual cost of ownership has been ~$350US per year. And if I did not have to drive one other person around, I think I could archive a single tank of gas per annum (being a devout ascetic really helps here) on a very good year (every trip is planned for highest efficiency otherwise). I also almost always get a $1 off the gas price by shopping at Kroger’s, which is like $0.80 and I only ever buy their so-called loss leaders when food shopping.

    Caveat emptor. Maybe some day we will get an honest apples-to-apples comparison for the poor. at least.

  51. jacksmith4tx says:

    I bought a used Volt and run it off my PV array. I got a poor mans V2G: Picked up a 1500w pure sine wave AC inverter and installed a switched junction box so I can keep my critical loads going independent of the grid. It’s not automatic but it works. Once we figure out the economics of V2G a cascade of technologies will supercharge it’s adoption. Tipping points will be when average EV batteries are over 80KWh and virtual power plants emerge (networked bi-directional EVs connected to grid) along with standardized connections and possibly even a digital energy coin to let you manage your production, consumption, time of use and demand response.
    Tesla is already doing some virtual power plant work with their Power Wall systems.

    Hey check out the science team Biden is putting together. It’s very broad and deep.
    Dr. Eric S. Lander to head the Office of Science and Technology Policy

  52. According to that MIT thingy, I already meet 2050 emissions standards.

  53. mrkenfabian says:

    Well, we cannot expect EV manufacturing to ramp up fast without help. But we cannot expect people to give up their ICE vehicles and stop being functional members of society whilst waiting; this is only going to get solved by our energy supply systems becoming very low emissions, so consumption, including manufacturing becomes low emissions. Personal lifestyle choices won’t do it, especially if only by those who care enough to make great personal sacrifices. Blaming people who care for failing to not only reduce their emission but counting them as responsible for the failure of those who don’t care for failing to reduce theirs in turn makes no sense to me – “I won’t unless they do first – but then, I might not do it anyway” is not good enough.

  54. Ah, the blame game. I am kind of the opinion that CO2 emissions don’t give a flip how much anyone cares about them. Kind of like COVID-19.

  55. Ben McMillan says:

    It is worth pointing out that the big ramp up in EVs happening now (one European country now has 50% of EVs in new car sales) is to a large extent lead by government regulation and incentives.

    In the UK, for example, people are now used to the idea that emissions regulations are going to get increasingly tight, and ‘Will I be able to drive this in London in 5 years time?’ is very much on the radar.

    But this is in combination with a willingness of people to spend a bit more upfront to do something they see as positive for the environment, and certain companies having a vision beyond the status quo. This is not just about CO2: a 20 year old banger might be cheap to run, but isn’t helping air quality much as you go crawling past the school gates in heavy traffic.

    Same for PV and wind: the market is awesome at reducing costs once governments force it to try. It helps too if there is decades of government-funded research helping to build a foundation.

  56. Chubbs says:

    Good point Ben. If we can adapt to climate change, we certainly can adapt to life with less and eventually no fossil fuels. In trouble if we can’t.

  57. Yes, I also find it odd that those who are very confident that we can adapt to climate change are also the ones who often seem to suggest that any attempt to adapt to a world that doesn’t rely on fossil fuels would be catastrophic.

  58. Bob Loblaw says:

    …and stop being functional members of society …

    My expectation is that different people often have very different definitions regarding the meaning of “functional members of society”.

  59. ATTP, I don’t see many making the argument that we cannot adapt to a world without fossil fuels. I do, however, see many who argue that telescoping the transition into too short a time frame will be disruptive. I am one of them.

  60. Let me just say that I wholeheartedly support our new EV overlords. The sooner the better. Same goes for any and all renewable energy technologies or any and all (near) zero carbon energy technologies. Private sector or public sector and everything in between.

    The original thrust of this post was the apparent lack of justified or realistic economic assumptions going forwards. Whist these IAM’s are based more on the known past rather than a somewhat unknown future.

    My main objection comes from my rather pessimistic POV of humanity in general (which should be rather obvious by now). We will never know what or where we get to until we get there. That previous sentence sounds like a Yogi Berra quote. 😉

  61. mrkenfabian says:

    Everett – I am of the view that action is needed whether people care or not and their future lifestyles need to be very low emissions, but as a flow on consequence of the energy supply being very low emissions – and the means to do that is an economy wide transition to low emissions energy beginning with electricity. When electricity is low emissions everything done using it becomes low emissions.

    Frugality helps but it is unlikely to be a popular solution or even a sufficient one, not even if it is widely taken up. Aiming for clean energy abundance seems like a better choice of direction, for as far as it can take us; other factors will put limits on it, but the inhibiting factor should not be lack of intent. EV’s have enormous potential, for more than reducing transport emissions – as additional energy storage that complements electricity networks running with solar and wind – to take as far as it can take us, but as one element.

    Bob, my household is low emissions by choice, but only relative to the profligate emissions of average and above average Australians. I do encourage reducing personal footprint by choice but without that overarching change to energy it will be insufficient. I am not going to go stone age and am not asking or expecting it of others – certainly not as a pointless attempt to prove I believe that a clean energy transition is necessary to self appointed hypocrisy police, who – hypocritically – will be unmoved by it.

  62. Ben McMillan says:

    I think one measure of success of developing plausible technology solutions is the rhetoric from those who want to maintain the status quo is shifting from “reducing carbon emissions is basically impossible” to “at some unspecified point in the future we should do something, but let’s not be too hasty”.

    For example, the Australian PM talking about net-zero “at some point in the second half of this century”.

  63. Pingback: Versione 2.0 – L'archivio di Oca Sapiens

  64. Pingback: Ignoring the Economists? | …and Then There's Physics

  65. Lucy says:

    I think it’s easier to cause the relevant party which you want them take action attention if connected economy and its impact. But if we inquire the model, uncertainty, how human’s activities effect the temperatures at the atmosphere from physical perspective, we’d better take action to protect the environment, such as protecting forests, invest clear resources, etc. not in the name of climate change.

  66. Chubbs says:

    I worry that we are afraid of change because our crystal ball is muddy. The world economy is built on fossil fuels. Seems logical that we will suffer when we transition away. But will we? Guessing we will find out this decade, if not the next.

Leave a comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.