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You step confidently into the gully, and suddenly tumble down a steep slope, barely surviving the fall. You scream at your scout: how could he make such a terrible mistake? His advice almost killed you!

He explains that, since it was difficult to survey the gully from East to West, he instead surveyed it from North to South. Then he assumed that the gully was shaped the same way East to West as it was North to South.

Normally I don’t like using analogies, but this one is a perfect rendition of how economists approached global warming—and also of why we have fallen for their deluded advice, and why this is so damn dangerous.

As someone with physical experience of our world, you instinctively understand that the scout in my analogy is insane. You know that landforms are not symmetrical, and that only a madman would assume that they are.

But you don’t have the same experience of climate. The climate variation you know is the climate variation across space. You know that temperature increases as you move from the Poles to the Equator, and you know the range of average temperatures is extreme—from well below zero at the North Pole, to about 30°C at the Equator. You also know that people live at almost all these latitudes, so human societies flourish across a 40°C range of temperatures.

On the other dimension of time, you have little to no experience. Even though the global average temperature has risen by one degree over the last sixty years {Neukom, 2019 #7216}, the inertia of the planet’s ecosystems has meant that the long-term effects of this increase in energy has not yet been manifest in truly enormous changes in the planet’s climate. The rain in Spain still falls mainly on the plain—though occasionally now in devastating dumps by “atmospheric rivers”, since the atmosphere can hold 7% more moisture than 60 years ago, thanks to that 1°C temperature increase.

Scientists now estimate that key components of the Holocene climate—coral reefs, land-based permafrost, the Greenland and West Antarctic ice sheets, and the Northern Hemisphere sub-polar gyre—will be tipped from their current state to an entirely different one by the 1.5°C increase in global average temperature that we have already experienced {Lenton, 2025 #7511}.[1] Going on the lifetime experience of a human however, it was possible to live through the change from 0.5°C to 1.5°C above pre-industrial levels over the last sixty years and not perceive any substantial change in the climate.

So, when economists tell you that they have assumed that global warming over time will have the same impact as temperature variation across the planet, you don’t instinctively know that, like the scout in my analogy, they are stark raving mad.

But they are. What happens across the 40°C range of temperatures that characterize climatic variations across space is nothing like what happens with much smaller temperature variations across time.

However, without any experience of climate change across time to go on—since the rate at which temperature changes because of global warming is (dare I say it!) glacial, compared the rate at which temperature varies on a single day—you are also liable to confuse climate across space with climate through time. This makes you susceptible to the bad advice from economists, and querulous about the good advice emanating from climate scientists.

After all, why should a mere 6°C of global warming cause a catastrophe, when you know that Florida’s temperature is 12°C warmer than New York’s, and its per capita income is only 20% lower than New York’s?

To cover the obvious, moving from New York to Florida increases the average temperature you experience by 12°C, and it might lead to your income falling by 20%. But it doesn’t cause the AMOC to collapse, or Antarctica to melt. There are tipping points through time, but there are no tipping points across space.

Why did economists ignore this obvious issue? In part, like the scout in my analogy, economists assumed that climate change across space can be used as a proxy for climate change over time, not because it was correct, but because it was easy.

Since it is difficult to predict the future (the East to West in my analogy), economists instead measured the present (the North to South). Then they assumed that the relationship between GDP and temperature which applies across the planet today (“North to South”) could be used to predict the future impact of global warming on the economy (“East to West”).

There is—there can be—no “data” on what global warming of, say, 3 degrees Celsius by 2100, will do to the economy in 2100. But there is plenty of data on both GDP now and temperature now, and it is easy to compare GDP and average temperature in one country with GDP and average temperature in another country.[2] Do some fancy econometrics, and you can come up with, not just a prediction of what might happen to the global economy if the global average temperature rises by 3°C, but an actual measurement of the difference in GDP caused by a 3°C difference in temperature today.

Then all you have to do is assume that what happens across space will happen over time, and hey presto, you can predict that 3°C of warming by 2100 will reduce GDP in 2100 by 3.1%, compared to what it would have been had there been no global warming at all.

This is in fact Nordhaus’s latest “prediction”, published in 2024 in the science journal Proceedings of the National Academy of Sciences (PNAS):[3]

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The proponents of these policies believed that they would accelerate economic growth so much, in comparison to the preceding “Keynesian” policies, that UK citizens would no longer need welfare, public education, or public health. Why accept the State’s services, when you will be so much wealthier that you can save for your retirement easily, and pay for private education and private health cover.

Whoops: when you check the data, Neoliberalism did not deliver on its promise of higher growth. Dating Neoliberalism from the mid-1970s, the UK’s per capita economic growth between 1975 and 2019 (thus leaving out the effect of the pandemic) was 0.8% per year lower than growth between 1956 and 1975.

This was not a British abberation, but the norm: virtually every advanced economy grew more slowly under Neoliberalism than it did under the “bad old” Keynesian period.

This video explains why it failed:

It comes down to two major factors:

• Neoliberalism deregulated the finance sector, and led to speculative lending rather than genuine investment; and

• Cutting the government deficit actually terminated fiat money creation, which led to less money being available to enable investment out of cash flow.

Starmer was therefore another political victim of Neoliberalism. Sold to political parties as the basis for continued economic and therefore electoral success, it has impoverished the working and middle classes, and led to its political champions losing office.

Six have lost office so far in the UK, without completing their terms. Since the next UK Prime Minister in Waiting, Andy Burnham, is likely to continue these policies, there are likely to be seven Prime Ministerial victims of Neoliberalism before the next UK election.

However, that change would take “centuries to millennia” to occur {Lenton, 2023 #7201`, Table 1.2.1`, p. 59}, which makes it sound far distant, not at all threatening to people alive today, and something to which we could adapt to over time.

There are, however, other potential “tipping points” which could transit from civilization-enabling to civilization-destroying states in your lifetime. This chapter details three of them, not because they are likely, but because they illustrate what climate change actually means. I hope understanding these phenomena, which global warming could feasibly trigger, will make it easier to understand how a rise in average global temperature of just a few degrees could destroy our sedentary civilization.

None of these are potential events is, as yet, a consensus prediction in climate change research—though research and data has shifted the first from a low to a high probability during the 21^st century {van Westen, 2024 #7416;Pontes, 2024 #7421;Ditlevsen, 2023 #7402}. However, all of them are the sorts of changes for which cost-benefit analysis is irrelevant: you simply should not allow any possibility of them happening. And yet they could happen on the current trajectory of global warming.

1. Termination of the “Atlantic Meridional Overturning Circulation”

The “Atlantic Meridional Overturning Circulation” (AMOC) is the Atlantic segment of an enormous circulation system, known as the Thermohaline Circulation (THC), which spans all of the Earth’s oceans—see Figure 2.

Figure 2: : An animation of the Thermohaline Circulation on Wikipedia at https://upload.wikimedia.org/wikipedia/commons/a/ab/Thermohaline_circulation.svg

The volume of water transported by the AMOC is hard for the human mind to comprehend. The unit of measurement that oceanographers use for the movement of water is called a Sverdup, and it corresponds to water moving through a cross section with an area of one million square metres—think of a square one kilometre on each side, or a pipe with a diameter of more than 1.1 kilometres—at a speed of one metre per second.

The discharge of all the world’s rivers into the planet’s oceans is equivalent to about 1.5 Sverdups. The AMOC moves about ten times this volume of water from the South Atlantic to the North as warm relatively fresh water near the surface of the ocean, and an equivalent volume of cold, salty water flows back in its depths. The amount of energy transferred is also near incomprehensible to the human mind: the heat the AMOC transfers makes the North Atlantic, and continental Europe, about 10°C warmer than they would otherwise be.

The AMOC has shut down over palaeontological timescales, but initial research into the stability of the AMOC implied that this would be unlikely to happen on a human time scale. Lenton’s 2008 survey—the one that Nordhaus so utterly misinterpreted—suggested that it would take between 3°C and 5°C of warming to cause it to shut down, and that the transition would take of the order of a century {Lenton, 2008 #5678`, Table 1`, p. 1788}.

Unfortunately, more recent research suggests that the AMOC could be turned off by as little as 1.1°C of warming {Lenton, 2023 #7201`, Table 1.4.1`, p. 125}, which we have already exceeded, and that the transition could result in European temperatures falling by more than 9°C over a mere three decades:

Atmospheric and sea-ice feedbacks, which were not considered in idealized climate models studies, further amplify the AMOC-induced changes, resulting in a very strong and rapid cooling of the European climate with temperature trends of more than 3°C per decade. {van Westen, 2024 #7416`, p. 7}

If this happened, then large sections of Northern Europe would become uninhabitable, not because of heat, but because of cold—while the rest of the planet would warm by an equivalent amount, though over a much larger area.

The timeline for this possibility has declined from centuries, in Lenton’s 2008 survey, to years in the most recent research. The most troubling research implies that this process could occur at any time between 2025 and 2095:

In this work, we show that a transition of the AMOC is most likely to occur around 2025-2095 (95% confidence interval). {Ditlevsen, 2023 #7402`, p. 2}

If it did, then quite possibly within your lifetime, much of northern Europe would become uninhabitable, while temperature volatility and a dryer climate would make much of the remainder of Europe both unliveable, and unable to feed itself:

The abrupt weakening or collapse of the AMOC would result in a climatic shift with profound regional, and even global, implications. Europe would become colder and drier, which would reduce agricultural productivity and render most land unsuitable for arable farming. {OECD, 2021 #6552`, p. 110}

If the AMOC tips, then the refugee crisis from global warming would not be one of Africans trying to cross into Europe, but of Europeans trying to cross into Africa. How well do you think they would be received, given how Europe is currently treating refugees from Africa?

Unfortunately, what happens in Northern Europe will not stay in Northern Europe. As well as causing a near-Ice-Age event in northern Europe, modelling by Lenton for the OECD implied that the combination of 2.5°C of global warming, and the loss of the AMOC, would result in a 70% fall in the proportion of the globe’s land area that is suitable for growing corn and wheat {OECD, 2021 #6552`, Figure 3.20`, p. 153}.

an AMOC collapse would clearly pose a critical challenge to food security. Such a collapse combined with climate change would have a catastrophic impact. {OECD, 2021 #6552`, p. 152}

A 70% fall in grain output would cause a global famine that would kill of the order of half the world’s population, even without taking into account the military conflicts that such a catastrophe would trigger.

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The economics chapter of the 2014 IPCC Report detailed all the studies since Nordhaus’s which calculated aggregate economic damages from global warming. None of these studies diverged from Nordhaus’s original fallacious assumptions about the nature of global warming—that it will only affect weather-exposed industries—and the industries it would affect. The coverage column shows the industries considered in each of these subsequent studies, and they are all restricted to the same set of weather-exposed industries that Nordhaus thought would be the only ones affected by global warming. Manufacturing, road and air transportation, communication systems, wholesale and retail services, government activities, and the finance sector, are all conspicuous by their absence. Even open cut mining, which Nordhaus later realised was exposed to the weather, is not considered—see Table 4.

Table 4: Summary of studies on economic damages from global warming, IPCC 2014 Report {IPCC, 2014 #5795`, Table SM10`, p. SM10-4 }

Furthermore, subsequent papers have also adhered to Nordhaus’s practice of stating the damages from global warming in terms of the difference between hypothetical future GDP with global warming, and a hypothetical future GDP in the absence of global warming.

These are the numbers that politicians and the media treat as serious estimates of the impact that global warming will have on human civilization. But they are, for want of a more technical term, complete bollocks. Not only are they based on transparently false assumptions, they also report estimated damages as a comparison of one future, hypothetical number—predicted output in the future with global warming—to another future, even more hypothetical number—predicted output in the future without global warming. This is very different to how economists normally make predictions about economic growth, which is with respect to the annual rate of change of GDP.

When you convert these superficially large damage estimates into predicted declines in the annual rate of economic growth, you find that not a single damage estimate by economists predicts a decline in the level of GDP, from any level of global warming. All of them predict that GDP growth will continue, just slightly more slowly, despite global warming levels of 7°C {Howard, 2021 #6898}, and even 8.6°C {Stern, 2007 #6163`, Figure 6.6`, p. 159}.

When Nordhaus first surmised that 3°C of warming would reduce GDP by 0.26 percent, what he meant was that he estimated that GDP in 2100 with a 3°C increase in global average temperature would be 0.26% smaller than GDP in 2100 would have been, if there had been no change in global average temperature. This is in contrast to the standard way that economists compare alternative policies, which is in terms of the impact on the rate of economic growth. However, there is a simple formula that enables these hypothetical comparisons to be converted into a prediction of the fall in the annual rate of economic growth:

• Convert the percentage of expected damages into a fraction by dividing by 100;

• Add the fraction of expected damages to GDP to one;

• Take the natural logarithm of this number;

• Divide this by the number of years between the start date of the analysis and the date when the damages are expected; [1] finally,

• Multiply the result by 100, and you have the predicted fall in the percentage rate of economic growth.

Applying this formula to Nordhaus’s pre-hunch estimate in his 1991 paper that 3°C of warming by 2100 would reduce global GDP by 0.26% (which is 0.0026 when expressed as a fraction), we get a prediction that this amount of global warming will reduce the rate of economic growth over the 109 years between 1991 and 2100 by 0.0024% per annum:

Statistical agencies report the recorded growth rate of GDP to one decimal place of accuracy: “the rate of economic growth last year was 3.1%”, for example. Nordhaus’s claim that 3°C of warming will reduce the annual rate of economic growth by 0.0024% is saying that the impact of 3°C of global warming by 2100 will be to reduce the rate of economic growth by one fortieth of the accuracy with which economic growth is measured today. It is a claim that the economic impact of 3°C of global warming will be literally unmeasurable in terms of the rate of economic growth.

Even his much larger “hunch” of a 2% decline in future GDP also resolves into a drop in the rate of economic growth equal to one fifth of the accuracy with which change in GDP is measured today:

As well as adhering to Nordhaus’s way of expressing damages, the overwhelming majority of these subsequent papers have also adhered to the magnitude of damages that he estimated. Only one of the studies shown in Table 2 reported expected damages of more than 3% of future GDP (Maddison and Rehdanz’s 2011 prediction of a 12.4% fall), while one paper (Tol 2002) predicted a 2.3% increase in future GDP from a 1°C increase in global average temperature.

A recent paper—“Rising Temperatures, Melting Incomes: Country-Specific Macroeconomic Effects of Climate Scenarios” {Mohaddes, 2024 #7498}—summarized almost all economic damage estimate papers since Nordhaus’s 1991 paper.[2] The majority of these later studies still report future damages similar to Nordhaus’s original 2% estimate—which, as noted above, translates to an unmeasurable fall in the rate of economic growth.

Figure 1:l Image taken from

{Mohaddes, 2024 #7498`, Fig 7. GDP impact of increases in temperature}

But even the largest estimate here—the 60% fall in GDP in 2100 from 4°C of warming predicted by Kotz et al {Kotz, 2024 #7413}—translates into a prediction that economic growth will continue, but just at a slower rate. The Kotz number predicts a 1.2% fall in the annual rate of economic growth between 2024 and 2100:

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Economics has been dominated by what is known as the “Neoclassical” paradigm ever since the 1870s. The Great Depression was a huge empirical anomaly for this paradigm, since it sees a market economy as being inherently self-stabilising. But that anomaly was forgotten as other events took its place, starting with World War II itself: the economic problem of WWII was not underemployment, but building armaments as quickly as possible for the war effort.

Then followed the post-War period of rapid growth and relatively stable prices in the 1950s and 1960s, which gave way to the inflation of the 1970s and 1980s, followed by “the Great Moderation” in the 1990s, the “Subprime Bubble” and “Global Financial Crisis” in the 2000s, the decade of post-GFC stagnation in the 2010s, the 2020s which opened with the Covid lockdowns, then post-Covid inflation, and now, the unfolding chaos of the war on Iran. The focus shifted from one economic phenomenon to another, and past failures with previous anomalous phenomena were forgotten.

History thus erases the failures of Neoclassical economics, by forgetting the anomalies which have contradicted it.

This is amplified by the teleological orientation of Neoclassical economics, which literally defines economics in terms of the purpose that it believes a market economy fulfils. The accepted definition of economics was crafted by Lionel Robbins in 1932, in a book with the portentous title of An essay on the nature and significance of economic science. In it, Robbins declared that:

Economics is the science which studies human behaviour as a relationship between ends and scarce means which have alternative uses. {Robbins, 1935 #5868`, p. 15}

This definition did not make empirical sense at a time Robbins developed it, which coincided with the depths of the Great Depression. At the time, 25% of the USA’s workforce—and 15% of the UK’s, and 30% of Germany’s—was unemployed. There were plentiful available, unused resources at the time—in the form of unemployed workers, and idle factories—and yet Robbins’ definition implied that resources were scarce, and therefore not idle.

However, this definition concisely expressed the belief that Neoclassical economists already had, that the market was the ideal system for allocating existing resources between members of society. It was adopted by Neoclassical economists, despite the glaring gap between the definition and the actual state of the economy in 1932.

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To understand how this happened, you need to know how refereeing functions, both in the wider academic community, and also in the peculiar confines of the discipline of economics—which I cover in the next chapter.

When a paper is submitted to an academic journal, the editor will firstly decide whether the paper fits the remit of the journal, and then effectively skim read it to decide whether it reaches his or her minimum standards for quality. If it does, then the paper is sent to academics who have previously published on the same topic, with a request that they referee the paper for the journal. Refereeing is a purely voluntary, unpaid activity, so the academics approached by the editor can decline the task.

Once two or more referees accept the editor’s request, the referees read the paper and assess its argument. Each referee will give written feedback on the paper to both the editor and the author, along with a recommendation to the editor which can range from “publish as is”, to advising the editor that the author needs to make substantial revisions to the paper, to outright rejection of the paper.

This process can be extremely useful for both the author of and readers of an academic paper. Refereeing can catch errors that the author missed, and also provide feedback to an author which improves their argument. Most published papers go through one round of editing as a result of feedback from referees, and quite a few undergo two or more rounds before the final version is approved by the referees, and later published by the journal. I have had this positive experience from refereeing myself on many occasions.

However, refereeing can also ensure that views that are outside the mainstream of a discipline are not published, even though they may later be proved to be correct, while mainstream views do get published, even though they may later be proved to be false.

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This, in and of itself, was potentially a worthwhile endeavour.[1] However, his estimates of the costs of climate change began with the assumption that only industries directly exposed to the weather would be affected by climate change.

Nordhaus divided American industry into three categories: those “such as agriculture and forestry, in which output depends in a significant way upon climatic variables”; those which are “moderately sensitive”, and finally, those which “are negligibly affected by climate change”. He put 3% of industry into the “Potentially severely impacted” category, 10% into “Moderate potential impact”, and he then described the remaining 87% of the US economy as facing a “Negligible effect” from global warming:

Table 5 shows a sectoral breakdown of United States national income, where the economy is subdivided by the sectoral sensitivity to greenhouse warming. The most sensitive sectors are likely to be those, such as agriculture and forestry, in which output depends in a significant way upon climatic variables. At the other extreme are activities, such as cardiovascular surgery or microprocessor fabrication in ‘clean rooms’, which are undertaken in carefully controlled environments that will not be directly affected by climate change. Our estimate is that approximately 3% of United States national output is produced in highly sensitive sectors, another 10% in moderately sensitive sectors, and about 87% in sectors that are negligibly affected by climate change. {Nordhaus, 1991 #5598`, p. 930. Emphasis added}

The 87% of industry that he assumed would be negligibly affected included all of manufacturing and mining, all non-water-based transport and communication, the finance sector, residential and commercial real estate, all wholesale and retail trade, “government services”, and even “Rest of World”—see Table 1, which reproduces Table 5 from Nordhaus’s 1991 paper “To Slow or Not to Slow: The Economics of The Greenhouse Effect” {Nordhaus, 1991 #5598`, p. 931}.[2]

Table 1: Table 5 from Nordhaus 1991, p. 931: “Breakdown of economic activity by vulnerability to climatic change”

Sector

Percent of GDP

Total National Income

100

Potentially severely impacted

3.1

Farms

2.8

Forestry, fisheries, other

0.3

Moderate potential impact

10.1

Construction

4.5

Water transportation

0.3

Energy and utilities

Energy (electric, gas, oil)

1.9

Water and sanitary

0.2

Real Estate

Land-rent component

2.1

Hotels, lodging, recreation

1.1

Negligible effect

86.9

Manufacturing and mining

26

Other transportation and communication

5.5

Finance, insurance, and balance real estate

11.4

Trade and other services

27.9

Government services

14

Rest of World

2.1

In the text, he stated that “for the bulk of the economy—manufacturing, mining, utilities, finance, trade, and most service industries—it is difficult to find major direct impacts of the projected climate changes over the next 50 to 75 years” {Nordhaus, 1991 #5598`, p. 932}

This is a remarkably stupid argument, even when measured against Nordhaus’s own assumptions.

Firstly, even if it were true that only activities that are exposed to the weather are affected by climate change—and it most certainly is not true—then why did Nordhaus assume that only “Water transportation” would be affected by global warming, while “Other transportation and communication” would be unaffected? Roads, trucks, cars, railways, airports, planes, and telecommunication towers, are all exposed to the weather.

Secondly, even if a roof did protect the contents of a factory from damage from global warming, no factory produces everything needed for its output. Every factory needs inputs from mines, farms, and other factories, in order to create its products. To receive those inputs, factories need functional transportation systems; to manage them, they need functional communication systems. Even if climate change did only affect weather-exposed activities, transportation and communication systems are exposed to the weather, and therefore, can be damaged by climate change. Climate-change-induced damages to transportation and communication systems which make them dysfunctional would therefore reduce the capacity of factories to produce output.

Thirdly, a direct impact on the industries for which Nordhaus found it “difficult to find major direct impacts … over the next 50 to 75 years” is the potential unavailability of energy (and other natural resource inputs). Since global warming is caused by our use of fossil fuels as an energy source, disturbances to the supply of energy because of global warming are likely, and will affect all of these industries. Without energy, nothing can be produced at all: as I put it in “A Note on the Role of Energy in Production”, “labour without energy is a corpse, while capital without energy is a sculpture” {Keen, 2019 #5507`, p. 41}. And yet this direct impact was not considered by Nordhaus.

Fourthly, Nordhaus’s assumption in this paper that mining will not be affected by climate change truly reveals how cavalier his analysis was, and how slack the refereeing and editing of this paper was. Underground mining may not be exposed to the weather, but open-cut mining is. This obvious mistake by Nordhaus was not picked up by the referee[3] who approved this paper for publication, nor by the editor. A later paper corrected for this error, but in doing so, confirmed that, by “negligibly affected by climate change”, Nordhaus literally meant “not exposed to the weather”, when he reduced his damage estimate by the 2% of GDP that open cut mining represents:

In reality, most of the U.S. economy has little direct interaction with climate… More generally, underground mining, most services, communications, and manufacturing are sectors likely to be largely unaffected by climate change-sectors that comprise around 85 percent of GDP. {Nordhaus, 1993 #5604`, p. 15. Emphasis added}

Lastly, the final row of Table 1, “Rest of World”, refers to exports from and imports into the USA, and effectively assumes that international trade is unaffected by climate change. This is ridiculous.

It is little wonder then that Nordhaus concluded that climate change was an economic nothing-burger. He asserted that 3°C of warming from a doubling of the CO2 concentration in the atmosphere would reduce America’s GDP by one quarter of one percent:

We estimate that the net economic damage from a 3° warming is likely to be ¼% of national income for the United States in terms of those variables we have been able to quantify. {Nordhaus, 1991 #5598`, pp. 932-33}

Table 2 shows his damage—and benefit—estimates for the “severely and moderately affected” sectors. The biggest numbers in this table are for the “Impact of greenhouse warming and CO2 fertilisation”, where the former is shown as potentially reducing GDP by $10.6 billion, and the latter as increasing it by $9.7 billion (in 1981 US dollars). He provides no numbers for five of the sectors, and his aggregate damage estimate of a fall in GDP of $6.23 billion is simply the sum of all the numbers in the table—including the negative and slightly smaller positive number estimating damages and benefits to farms.

Table 2: Impact estimates for different sectors, for doubling of C02, U.S. (positive number indicates gain; negative number loss) {Nordhaus, 1991 #5598`, Table 6`, p. 932}[4]

Sectors and damages in Billion (1981 $)

Severely impacted sectors

Impact of greenhouse warming and CO2 fertilisation -10.6 to +9 7

Forestry, fisheries, other: Small + or -

Moderately impacted sectors

Construction +

Water transportation ?

Electricity demand -1.65

Non-electric space heating 1.16

Water and sanitary -?

Loss of land -1.55

Protection of sheltered areas -0.9

Protection of open coasts -2.84

Hotels, lodging, recreation ?

Billions, 1981 level of national income -6.23

Percentage of national income -0.26

He hedged his bets with respect to “unmeasured and unquantifiable factors”, but ultimately stated that “my hunch is that the overall impact upon human activity is unlikely to be larger than 2% of total output” {Nordhaus, 1991 #5598`, pp. 933}.

“Hunch”? What is that word doing in an academic paper? Hunches are for newspaper columns and blogs, not academic research. However, given this “hunch”, the most important thing about climate change, according to Nordhaus, was not to waste resources in fighting it:

Climate change is likely to produce a combination of gains and losses with no strong presumption of substantial net economic damages. This is not an argument in favour of climate change or a laissez-faire attitude to the greenhouse effect. Rather, it suggests that a careful weighing of costs and damages will be necessary if a sensible strategy is to be devised. {Nordhaus, 1991 #5598`, p. 933}

No reputable newspaper at the time would have let errors like Nordhaus’s be published in an Op-Ed—remember, this refereed academic paper was published in 1991, well before the Internet destroyed the business model of newspapers. In 1991, leading newspapers had experienced sub-editors who routinely checked articles for errors.[5] They lacked the scientific training to see the problems in Nordhaus’s identification of weather with climate, but they would surely have noticed that “Other transportation and communication”, opencut mining, and the “Rest of World” are exposed to the weather, and therefore should be moved out of Nordhaus’s “Negligible effect” category.

Why were these obviously weak aspects of Nordhaus’s paper not flagged and amended by the refereeing process at this prestigious journal? If newspaper sub-editors would have caught mistakes like these, why did academic referees fail to do the same?

[1] Before he began to estimate these costs and benefits, he let slip his preconception that the damages from global warming would be trivial. After noting that “Current reviews suggest that a doubling of C02 or its radiative equivalent, will in equilibrium increase global mean surface temperature by 1° to 5°C” {Nordhaus, 1991 #5598`, p. 921}, Nordhaus said “For example, say that a doubling of CO2 in equilibrium reduces world output by 1%” {Nordhaus, 1991 #5598`, p. 926}.

[2] I have omitted a column showing the sizes of these sectors in 1981 US dollars.

[3] Normally, two referees are assigned to an academic paper. This paper, and Cline’s from the same issue, {Bernanke, 1991 #1593}, both had only one referee.

[4] I’ve omitted labelling rows, except for the “Severely” and “Moderately” impacted sectors labels.

[5] The fact that quality control in newspapers has declined dramatically since the 1990s was thrown into stark relief by a 2026 New York Times headline which mused about a “North American Treaty Organization without America”, showing that its journalist, sub-editors and editors apparently did not realise that the A in NATO stood for “Atlantic”, not “America”. See

https://x.com/shaunrein/status/2040218512875237769?s=20

.

One of leading scientists in this field is Tim Lenton, who is the Professor of Climate Change and Earth System Science at the University of Exeter in the UK. In 2008, he conducted a survey of experts on what were then regarded as the nine major and most vulnerable such tipping points. These included sea ice in the Arctic Ocean during summer, the Greenland ice sheet, the Amazon rainforest, and six other large elements of the planet’s current climate. The paper was titled “Tipping elements in the Earth’s climate system”, and this was its conclusion:

Conclusion

Society may be lulled into a false sense of security by smooth projections of global change. Our synthesis of present knowledge suggests that a variety of tipping elements could reach their critical point within this century under anthropogenic climate change. The greatest threats are tipping the Arctic sea-ice and the Greenland ice sheet, and at least five other elements could surprise us by exhibiting a nearby tipping point. (Lenton et al. 2008, p. 1792. Emphasis added)

I was first alerted to the existence of this paper by William Nordhaus, the economist who was awarded the “Nobel”[1] Prize in Economics in 2018 for his work on the economic impact of climate change (Nordhaus 2018a). In the manual for his model DICE (“Dynamic Integrated Climate and Economy”), Nordhaus stated that the function he used to relate an increase in global temperatures to a decrease in GDP:

assumes that damages are a quadratic function of temperature change and does not include sharp thresholds or tipping points, but this is consistent with the survey by Lenton et al. (2008) (Nordhaus and Sztorc 2013, p. 11. Emphasis added).

He elaborated on this remark in his book The Climate Casino (Nordhaus 2013a):

There have been a few systematic surveys of tipping points in earth systems. A particularly interesting one by Lenton and colleagues examined the important tipping elements and assessed their timing… Their review finds no critical tipping elements with a time horizon less than 300 years until global temperatures have increased by at least 3°C. (Nordhaus 2013a, p. 60. Emphasis added)

Pardon me for stating the obvious, but Nordhaus’s interpretation of this paper is almost the exact opposite of what the paper actually said…

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“Don’t overrate sincerity,” a voice boomed from the back of the room. “The most sincere person you’ll ever meet will be the maniac chasing you down the street with an axe, trying to chop your head off!”

The room was a senior school classroom in a Catholic boys’ school in 1969 in Sydney, Australia, and the voice belonged to our religion teacher, Brother Gerard.

Unlike most of his freres, Gerard did not shove a catechism down our throats, but let us engage in ethical and political discussions, which were chaired, not by him, but by the students themselves.

Normally, Brother Gerard said not a word. But in one class, as we were vigorously debating some politician whom half the students praised and the other half derided, someone interjected “Well, at least he’s sincere!”—a proposition with which the whole class agreed. And then Gerard dropped his stunning truth bomb.

I never found out what events inspired Gerard’s epiphany, but I’ve come to appreciate its wisdom all the more over the years. It’s related to the saying attributed to Mark Twain, that:

It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so.

Putting these two aphorisms together leads to the insight that the most dangerous people on the planet are those who sincerely believe something which is false. This is in contrast to Upton Sinclair’s well-known quip that “it is difficult to get someone to understand something, when his income depends on him not understanding it”. This is true, but it is a second-order phenomenon when compared to false belief. Someone who is paid to misunderstand something won’t fly a plane into a skyscraper, no matter how much they are offered. Someone who believes will.

The most dangerous sincere believers on this planet are not religious extremists, but mainstream economists. They will destroy capitalism, precisely because they falsely believe that it is indestructible.

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I was supposed to finish this book in March of 2025. Instead, I put it aside to write two other books in response to the conventional madness on economic policy promulgated by Rachel Reeves (as Treasurer) in the UK and Elon Musk (as one-time head of Donald Trump’s Department of Government Efficiency). I finished the latter book Money and Macroeconomics from First Principles for Elon Musk and Other Engineers (see https://www.amazon.com/Money-Macroeconomics-First-Principles-Engineers-ebook/dp/B0FLWJ8LXY/); I left the former unfinished, because of the urgency I felt to set Musk straight on the foolishness of his economic analysis.

I am now back working on How Economists Will Destroy Capitalism, with the objective of finishing it by the end of June this year. Partly to pressure myself to finish it on time, and partly to get my argument out before a giant El Nino commences this year, I will be serialising it on this site, at one chapter per week.

There’s just one catch: since Polity Books is publishing this book, I can’t make it freely available here. Instead, for copyright reasons, the serialised chapters will only be available to paying subscribers. Each post will include a freely-available “teaser”, and then the full text for paying subscribers. Once the book is published, as per the contract I will delete these posts, and revert the site to its standard free-access status.

Polity has also agreed to offer paying subcribers a 20% discount on the list price, once the book is published. This is the relevant clause of the publishing contract:

16.11. It is agreed that the Author may publish draft chapters of the Work on his Substack and Patreon sites, on the condition that they are only accessible to those who pay for subscriptions for the Author’s pages on those sites, and that they are taken down before the book is published. It is further agreed that paying subscribers to the Author’s Substack and Patreon sites will be given the opportunity to purchase copies of the work from the Publisher at a discount of 20% from the published price.

I’ll start that serialisation this week, on Friday, and I will publish one chapter each week. I will commence with the entire first chapter, since that sets the scene by arguing that the most dangerous people on the planet are those who believe something which is false. The cartoon below, done by my friend and collaborator Miguel Guerra, is part of the book’s artwork. In case you’re wondering, the bloke in the dunce’s cap is William Nordhaus.

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This time, the canary is the Orange Man, Donald Trump. But rather than warning of imminent danger by dying himself, his reckless actions will kill many non-combatants in the ludicrous and unnecessary Middle East war he started.

That, ironically, may be the early warning humanity needs to wake up to the dangers we face from global warming. The closure of the Strait of Hormuz will have nothing on what global warming will do to the production system of the planet. But, if it leads to some white people dying of starvation—rather than the usual story of famines only hitting brown people—then the world’s politicians and media pundits might finally realise how fragile, rather than robust, our civilisation is.

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