Professional and hobbyist gardeners who raise CO2 levels in greenhouses and grow-tents to increase yields and growth rates will tell you that in addition to the fertilization effect, higher CO2 levels also decrease the demand for water and thus not only save on resources but mitigate the other negative consequences of intense irrigation.
The reason is that in order for land plants to absorb CO2 from the air, they must open pores in their leaves which also allows moisture to escape, which must be replaced or the plant with wither, especially in hot and dry conditions. The higher the ambient levels of CO2, the tighter the plant can close the pores, and the less water it loses it producing the same amount of useful material. The tables illustrating this trade-off have been well- established and well-known for generations for every variety of plant in every combination of growing conditions, they are hardly secrets. And yet one rarely encounters any official analysis of climate change costs that appropriately weighs this benefit.
Terrible reading comprehension. Come on man, I literally put the word professional in front, to contrast the hobbyists from professional growers who run large commercial greenhouse operations. But while few people know the details of such large businesses, millions of people do indeed grow hobby quantities of plants in tents using co2 tanks or generators, and they are all intimately familiar with the same facts that the professionals and agricultural scientists know. It is of course the scientific consensus in horticulture that higher CO2 levels definitely increase yields while reducing water loss. It is the industry of producing reports that are all downside and no upside that have not caught up the agricultural consensus and the economic consensus.
"Every variety of plant in every combination of growing condition." This is your claim. But much less than 1% of agriculture is undertaken in these conditions and some types of agrictulture not at all. Further, evapotranspiration is not the principal way in many environments that water cycles through the system, rather it is evaporation.
There have been extensive experiments on the relation between CO2 and yield, including indoor experiments, open field experiments, even one that looked at random variations in CO2 concentration across the US correlated with local yield data. They differ in how strong they find the relation to be but the general relation is consistent and well established. Increased CO2 concentration raises yields for C3 plants, reduces water requirements for both C3 and C4.
For you to invoke the phrase “scientific consenuss in response to the above demonstrates that you fail to understand that while there is a scientific consensus that the climate is warming, and that human activity is a major component, in fact there is *no* scientific consensus that this is an existential risk, nor on the public policy prescriptions leftists like yourself worship.
I think it is a mistake to think about climate change as a scientific problem. It is actually an economics problem.
If we are to be endangered by climate change, what that means is that people's standards of living in the future will be reduced over what they would be if there were no climate change. Those who favor high climate spending believe that by spending more today that will save future generations a much greater expense protecting themselves from having to build giant sea walls to protect coastal cities, etc.
True, living standards will be higher in the future if those living then don't have those heavy expenses. But living standards are not a function only of one's necessary expenses, they also depend on one's income. There is an implied assumption behind all climate change spending that it will not have any effects on future incomes. That is false.
Why do living standards rise over time? Only one thing - rising human productivity, which is almost entirely a function of savings (income we don't consume) invested successfully in things that raise productivity--R&D and better technology, capital goods and processes. But the purpose of climate change spending is not to raise productivity, it is to reduce our carbon dioxide emissions. Those are not the same thing.
We can concede that alarmist climate change models are correct, if we want to avoid scientific arguments that are over most people's heads, and still argue that the world will end up worse off by even moderate climate change spending, because it diverts business investment from its traditional goal of raising productivity and thus incomes toward instead cutting down on CO2.
The amount saved and invested is a small percentage of our incomes as is, especially with so many governments dissaving by borrowing to consume. Diverting most investment away from trying to enhance productivity will doom most economic progress, with possibly dire political and social consequences that endanger us more than the climate might.
"If we are to be endangered by climate change, what that means is that people's standards of living in the future will be reduced over what they would be if there were no climate change."
That "endangered" assumes no upside, or that upsides and downsides can be accurately measured and downsides are greater.
Two examples of upside: increased CO2 means more plant life, and warm climates kill far fewer people than cold climates.
Personally, I have zero faith in the ability to predict climate 75 years from now, and measuring the unpredictable upsides and downsides is just a joke.
I agree, but lack even the pretense of scientific knowledge enough to let me defend that argument. My point is that even if everything bad they say will happen to us because of climate change does happen, we would likely be able to handle all those things if we were a very rich society with high incomes. To the extent that directing R&D toward reducing CO2 rather than increasing productivity, we will be a much poorer society because our incomes will be much lower and be worse off even if our climate mitigation expenses are somewhat lower as a result.
In my book I pointed out that income per capital has risen by about 2%/year since the data series began in 1929. If by paying scientists and engineers to work on reducing CO2 emissions rather than working on increasing productivity, that reduces our income growth to about 1%/year, then people fifty years from now will have substantially lower incomes than otherwise, and it is unlikely that any reduced climate mitigation costs then could come close to making up the difference. IOW, we will be much worse off, even if we do a good job of reducing CO2 emissions. And it is far from clear that the subsidies and mandates will come close to accomplishing their ostensible goals.
Every argument other than “existential risk” for leftist public policy prescriptions on climate is preposterously bad economics, even if the sign DF notes were known, and the magnitude were approximately known.
And not only is there no scientific consensus at all on “existential risk”, most of the leftists who themselves push their “climate change” policies oppose nuclear energy - which of course should not merely not be opposed but should be actively pushed as by far the best short and medium term way to address something that is an existential risk.
Which is a huge part of why I say almost all “climate change” advocacy is primarily political.
There are two reasons I don't believe the "climate crisis" is any such thing.
1. The proponents have lied too often, committed too much fraud, and failed every prediction (polar bears going extinct, no more snow) for me to trust anything they say. People with the truth on their side simply do not need to resort to lies and fraud.
2. If I thought the climate crisis was an existential threat in 10 years, I would do everything possible to push for nuclear power. Nothing else could possibly be implemented fast enough. Yet they don't. Ergo, they don't believe their own claims. Ergo, I don't either.
One need not know much at all about any field to detect those two flaws. When they tell me to trust the experts, I remember that "expert" comes from the Greek X for unknown and "spurt" for a little drip under pressure.
I said "proponents", not "credible scientists", which is too subjective to have any meaning. "Consensus" has also been bandied about too much to have any meaning.
Very first entry predicts extinction of emperor penguins by 2100.
18 May 1972: From The Tuscaloosa News, Washington (AP), quote: "Arctic specialist Bernt Balchen says a general warming trend over the North Pole is melting the polar ice cap and may produce an ice-free Arctic Ocean by the year 2,000".
Of course, by definition all failed past predictions are no longer credible, and all future predictions are untested. So that may not be good enough evidence for you.
I don't think I understand your argument that spending on mitigating climate change reduces our productivity. Doesn't spending on climate change, in addition to the long-term cost avoidance that you cited, also push productivity forward? Development of clean energy technologies, energy efficiency technologies, and electric vehicles all seem like they enhance productivity. What is the evidence that resources that are currently being spent on mitigating climate change would otherwise be spent in such a way as to advance productivity more than this? I am not saying it would not, I am simply saying I don't see the evidence that it would.
That might be true, but only in the cases where the spending does improve productivity, as opposed to say meeting arbitrary and useless standards or attempting to solve a problem that doesn’t exist.
By way of analogy, say I want to improve the efficiency of my house energy wise. I can spend basically all the money I will ever have on that, but the net productivity side is not guaranteed for every dollar. Maybe I put more insulation in the attic, and that saves on air conditioning, but I probably shouldn’t spend so much I fill the entire attic to the rafters. Likewise, some spray foam might help seal cracks, but I could blow a lot of foam into the basement and not improve things at all.
Interesting analogy, but it doesn’t prove climate mitigation spending reduces overall productivity. Do you have evidence that the net effect is negative, or are you just arguing some projects are wasteful?
I was trying to explain the argument, not prove it. Spending on X does not necessarily improve productivity, regardless of what X is. It can even lower productivity. So if one wants to claim that spending on X will increase productivity, that needs to be shown and not assumed. (I would argue further that the burden of proof is on showing that it increases productivity on the basis that improving productivity is really hard, so most spending will not increase productivity.)
I was responding to Rick Teller's argument that climate change mitigation spending is reducing productivity. He presented no evidence to back his assertion. I noted that there is some evidence that climate change mitigation spending does increase productivity and requested a counterpoint argument. I infer, from your statement that you should not assume spending on X will increase (or, presumably decrease) productivity, that you also agree that Rick's argument lacks proof.
I find that both the left and the right consistently put forth specious claims with little evidentiary support. While I don't always agree with Professor Friedman, I appreciate that he attempts to provide support for the positions he takes.
Sorry, minor correction: I did read Rick's original argument; I thought you were referring to the other posts in this threads that I assumed you had meant to respond to instead of mine.
Rick's argument is that businesses by default seek to improve productivity by whatever means possible, and so if they have to be forced to spend money on X, then X must not improve productivity as much as the things they would rather spend on, or else they would be spending on it anyway. In other words, the presumption should be, absent evidence to the contrary, that spending on "clean energy" and electric vehicles should not be expected to improve productivity. I leave out energy efficiency because businesses do actively pursue that, although perhaps not so much as regulators think they should.
I have not read Rick's argument, but rather am pointing out that there is no a priory reason to assume spending increases productivity, and indeed there is reason to presume it decreases it until shown otherwise. That's all.
IANAE but I'd say opportunity costs matter. When government forces spending resources on unnecessary projects, it diverts those resources from more worthy projects. Coerced projects are the least useful almost by definition, since if they had been useful, coercion would not have been necessary.
"Coerced projects are the least useful almost by definition, since if they had been useful, coercion would not have been necessary."
This is a very broad and rather bold statement.
If you believe that an unrestricted free market is the most efficient way to allocate resources, you are probably overlooking externalities that pricing ignores. But calling any kind of rule or regulation "coercion" oversimplifies how policies can fix market failures.
While IAANAE, and I agree that coerced projects may not always be the "most useful" (whatever this means) use of resources, that is true of almost all projects, coerced or not. But to go further and assert that coerced projects are the least useful assumes that the coerced project must be so nearsighted as to be completely devoid of benefit. Do you think electrification or the space program were the least useful use of the resources they required?
Are you able to clarify how this relates to spending to mitigate climate change? Governments have been imposing regulations, taxes, and providing incentives to promote a "green" agenda. By "coerced projects" are you referring to the development of electric cars and advanced battery technology? Are you referring to the plethora of markets created to develop energy efficiency technologies? Are you referring to the vast number of renewable energy technologies being developed?
I am an economist, and you are misusing these concepts.
You point out externalities in markets, but ignore externalities in government projects and regulations and government failures.
Coercion is precisely the word for government action. Sometimes coercion is the least bad option, but that is the mechanism by which governments function.
If we assume halfway rational actors, the chosen projects will generally be more efficient than those that require coercion to do. While it is true that sometimes people are wrong, what choices people making freely are almost always better than the choices they must be forced into when the measurement is their own interest.
Regarding "Are you able to clarify how this relates to spending to mitigate climate change? Governments have been imposing regulations, taxes, and providing incentives to promote a "green" agenda. By "coerced projects" are you referring to the development of electric cars and advanced battery technology? Are you referring to the plethora of markets created to develop energy efficiency technologies? Are you referring to the vast number of renewable energy technologies being developed?" Yes- one would be correct to presume that if people won't spend their own money on these projects but instead government has to take money that would be spent elsewhere and invest it in those places that people generally do not believe those are efficient uses of capital.
Yes, I neglected to mention that government projects also create externalities, but this does not negate my contention that government policy can mitigate market failures.
I am not sure what a "halfway rational actor" is. You are making a general statement that private actors will engage in projects that are "generally more efficient than those that require coercion to do." But, when we are talking specifics, namely, the numerous regulations, taxes, and incentives of the green agenda, what is your evidence that, absent these policies, the applied capital would have resulted in greater productivity gains in other projects?
As I am not an economist and I probably have an overly simplistic view of things, I think companies are generally motivated to pursue projects that will bring the greatest returns (generally monetary) to them in the short term. Investing in increasing productivity may, but also may not, result in the greatest short-term returns. Capital intensive projects that require long-term development, even though they may result in greater productivity gains, and a greater IRR (or is it MIRR?) are less likely to be pursued because of the long-term nature of the returns.
Some examples of this are the space program, which, I believe, advanced technology and productivity significantly, and cost-effectively and the 2002 mandate for TVs to incorporate digital tuners by 2007--which the industry strongly opposed, claiming it would add hundreds of dollars to the cost of each TV.
I don't believe that ALL government interventions (or if you want to call it 'coercion') are more efficient than the market and I also don't believe that ALL government interventions are less efficient than the market. Do you disagree?
So, the question is whether green interventions improve or decrease productivity? I think it would be more informative to argue for or against specific interventions with either empirical data or at least some intervention-specific arguments (e.g., I believe the government's developing/building/selling electric car "coercion" is rapidly advancing the technology of self-driving vehicles, which, I believe, is a significant productivity enhancer.)
I am not an economist. I don't know the Econ definition of externality, nor understand Pigou taxes. I've probably even got that little bit of jargon wrong.
But I take a real dim view of most justifications for government collective coercion. Take pollution, for example.
* If it's harmful, then it's measurable and traceable back to its origin, and ought to be prosecutable by its victims. Governments and cronies don't like this. A book on the history of New York City oysters, details of which I have forgotten but may be "The Big Oyster" by Mark Kulansky, tells of New York City sniffer squads, from the 1800s into the 1900s, tracking down pollution sources, and forensic analysts of the late 1800s tracking down pollution, such as soot on clothes drying outside, to show who to sue. This individual responsibility began to be outlawed by courts and legislatures on the grounds it did not take the public good into account; it was up to the government to decide how much pollution the nation could tolerate, and woe betide any individual who thought otherwise (Supreme Court of Georgia, Holman v Athens Empire Laundry Co., 1919: "The pollution of the air, so far as reasonably necessary to the enjoyment of life and indispensable to the progress of society, is not actionable").
* Victim prosecution and losers pays solve all sorts of problems. Third party prosecution, such as by governments, creates problems. When authority exceeds accountability, you have corruption. When accountability exceeds authority, you have scapegoats.
Coercion is not a mystery. Can the government jail you upon threat of death for not obeying their diktat? That's coercion.
I trust markets a thousand times more than I trust governments. And frankly, I don't care if a few fat cats get fat from providing what customers want. Bezos, Musk, Zuckenberg, Ellison, Gates, I despise and applaud them all in varying degrees, but there's not a single one deserves to be investigated by the government merely for building huge successful companies. They did so by satisfying customers, and in free markets, customers are king. All their companies will probably be as forgotten in 20 years as Alta Vista and MySpace are today.
Many years ago, I got to wondering what all the hubbub was about The Fed, and began exploring its history. The Panic of 1907 had a lot to do with creating the Fed, and the Fed didn't solve any of the problems which caused the Panic of 1907. Looking at its causes led to previous Panics and their causes and "fixes". To make a long story short, I concluded that government has caused far more problems than they've fixed. Governments murdered 100 million civilians in the 20th century, not including wars. The Mafia, drug cartels, and robber barons haven't come close.
Social and political problems are caused by governments too often to waste time in the few caused by individual bad actors, who are usually government cronies anyway, and whose victims are forbidden from prosecuting them by governments.
If our uncertainty about the net effects of climate change is so great that we can't even determine the sign, we certainly shouldn't be spending resources trying to change it.
To justify large expenditures, we'd need to know that the sign is negative and the effect is large.
Public statements by climate scientists leave out more than they keep in. Example, AR6, the 6th assessment report which was released in approved form in early 2022 had these three things to say about recent trends in floods:
1. We don’t know from observations whether floods have increased or decreased globally in the recent past. We'll have to try and infer it from other lines of evidence.
2. Changes in heavy rainfall suggest that floods might have got worse.
3. Changes in peak streamflow in rivers and waterways suggest that floods might have got better.
Only #2 made it into the executive summary. And by the time it makes it into the press release it’s a racing certainty.
The biggest example that occurs to me is analyzing what government should do on the implicit assumption of a philosopher king government, the state assumed to take the actions the economist thought it ought to take — the mistake corrected by Public Choice theory. That was very much the orthodoxy. Probably 1960's Keynesianism qualifies as well.
You are certainly correct about Public Choice theory. But the philosopher king assumption is so, so, so ... nice! We did mean so well. I suppose some climatologists mean well, but I'm sure not all. Philosopher king was not a means to destroy freedom and capitalism, but climatology is.
I'm sure you are correct about 1960's Keynesianism, too. I personally never had the problem because I was blessed with a truly horrible undergraduate textbook in the subject, and a truly great graduate course in the subject. Good textbooks did come out.
I've not seriously followed Macro, but I see primitive Keynsianism in the newspapers, on the Left, and in Britain. Public Choice has hardly been engaged with in the newspapers, on the Left, or in Britain.
So, we're still shaded, though surely not as much a climatology.
"To see how a mistaken consensus could be maintained imagine, very improbably, that my arguments convince Greenstone or Duffy that there is no good reason to expect climate change to have net bad effects and he publishes that conclusion. He would be converted in the eyes of friends and colleagues from a respectable academic to the climate equivalent of a biologist who rejects evolution, a nut case, a “denier,” would suffer very large costs, social and professional. It is prudent to avoid pursuing lines of thought or research that might lead to such consequences."
That is exactly what happened to Judith Curry.
Judith Curry is an American climatologist and former chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology. She has been a prominent figure in discussions about climate change, known for her nuanced and sometimes contrarian views.
She has been vilified and turned into a pariah. John Stossel interviewed her here : The FULL Judith Curry Interview: Climate Scientist Says World Won't End https://youtu.be/U0PQ1cOlCJI?si=8eEnxkaTbWjBzou1
...Any substantial change has some negative effects; to argue for government action to prevent a change you need to show that the net effect is negative, that costs are greater than benefits...
And you also have to show that the costs of mitigation are low enough to at least balance the improvements. I think this is a very high bar.
It seems outrageous to me that Govt can claim these sweeping powers with this rationale. I can think of a multitude of counterarguments to add to David's, but how about these additional:
1. Sulfur (lack thereof) in the atmosphere is an incredibly clear causation to global warming, much more so than CO2. Yet the govt is not just permitting that "harm" to be done, but mandating it.
2. USA has been flat or reducing emissions, and as such we are irrelevant as a causal factor for CO2-based warming. There is no argument to be made that sweeping powers (limited to the USA) are necessary to address global warming, because that's not a possible outcome.
3. Extreme weather -- The news always pins events on global warming, but I wasn't aware that it was scientifically valid. Certainly it's invalid to pin the California fires on Global warming. And again - warming has been mild until the last 2 years, DUE TO THE SULFUR
The whole thing (bad thinking) drives me up the wall, especially from the "trust the science" crowd.
Let's conduct a thought experiment, rather than getting into the weeds of climatology, measurement bias, the proven weakness and inaccuracy of climate change models, the actual effects of CO2, the irrefutable fact that climate experts have provided us with inaccurate predictions of catastrophe for the past 40 years, etc.
We'll go to "opposite world," where the claims are that global temperatures are falling, winter temperatures are dropping, summer growth season is shortening, blizzards and the damage they cause are intensifying,, ice is growing in the polar regions affecting global ocean currents, and "experts" tell us that we are in danger of another "ice age." Oh wait, some of that actually happened in the 1970s, ... whatever.
But back to opposite world and the coming ice age. Would today's experts suggest that we increase CO2 production to raise temps? Would they pass legislation that outlawed any attempt to use alternative ("clean") energy sources? Would they mandate the elimination of EVs by 2035? Would they allocation billions in federal funds to raise global temps? Would some activists suggest that countries producing low levels of CO2 transfer funds to countries producing more CO2 (to help raise temps)? All of those things seem crazy, but dropping temps are a "threat to future generations," aren't they? Remember, we're in opposite world, so it's likely that they would answer YES to my questions—to "save the planet," don't you know.
Whether we're in our current reality or in opposite world, it might be a better idea to proceed more thoughtfully and slowly, eschewing the very unscientific notion that "consensus" in science means the truth is known (it does NOT), that treating a complex multi-parameteric problem with religious intensity is necessarily a rational approach, or that hysteria, driven by political viewpoint, is a produ ctive way to make wide-ranging decisions that have significant unintended consequences.
'There is no mention of the fact that human land use at present is limited by cold, not heat,...'
I have seen claims that the Sahara is expanding southwards due to global warming. If true, this is presumably one place where human land use is limited or even reduced by heat?
The Sahara is hot, but less hot than some areas, including some in Africa, that are densely populated. It's lack of population is a combined effect of heat and lack of water.
If true, of course that would be a cost of getting warmer. But every report I have seen says the Earth is greening, adding more green (plant life, not eco warriors) cover and shrinking the Sahara.
That might well be, but I recall the Sahara was getting bigger back when global cooling was the fear. Then again I was pretty tiny, so maybe I am mixing memories a bit on the timeline.
It is worth noting though that the Sahara spreading a degree of latitude south would change a tiny amount of land compared to the arctic circle moving north by a degree of latitude. The Northern landmasses are immense.
Yes, I agree that the net effect of global warming is probably more arable land, not less. But I am not convinced that there is no loss of arable land at all due to higher temperatures.
The northern landmasses may look immense on a map, but they are less immense if you look at a globe. The distortion of a map increases with longitude. For instance, Greenland is actually smaller than Algeria but usually looks much bigger on a map.
If you read the piece of mine I linked to, you will find an estimate for loss of land from rising sea level. There might well be places where climate change makes land less useful, but what reason is there to think that, even if we ignore the shift of climate contours towards the poles, there will be more places made worse by the change than better? One of the predictions is increased rainfall, which should make places less dry. It isn't as if the present climate was designed for our benefit.
Just to be clear, I am not arguing that more places would be made worse than better. On the contrary, I agree with you that more places would be made better than worse. My only point - on which I see now that we are also in agreement - is that some places will be worse off, even if the overall effect for the world is positive.
I am not saying that there is not arable land lost, and I don't know that anyone else here is either.
Understood on the projection distortion of maps, but the land mass of North America, Asia and bits of Europe that are above the Arctic Circle are much larger than just Greenland, right? There is very little ocean between them, relatively speaking.
I don't think they need to establish that climate change is net negative for the purposes of the statute, just that it creates a risk of harm to public health or welfare. Rising temperatures are likely to do that somewhere (eg. heatstroke deaths in Arizona, fires in California), regardless of whether doubled crop yields end world hunger and Alaska becomes inhabitable.
Because you are not an expert on this and don't seem to want to bother to read AR6, run it through an LLM and see if it can answer your question on net negative effects of climate change.
“Hence to argue against such policies one does not, as Greenstone and Duffy assert, have to claim that the negative effects do not exist, only that they are at least balanced by positive effects.”
“ What struck me about the Axios story was that neither the author nor the academics quoted appeared to have thought about that question”
Due respect, but you are off base here, because you assume - either implicitly or explicitly -neutrally political good faith on the topic.
(Most) Leftists argue for such policies because it serves their political interest. Not quite “Period”. But primarily. And SURELY for the press writing articles such as these.
On a different, though related, point:
The “scientific consensus” is solely that the planet is warming and that human activity is a major component of that warming.
There is in fact NOT a scientific consensus that climate change is “bad”. Even as I don’t deny for a second that the large majority of the scientists who have gone into the field claim that it is bad and advocate for policies to combat it.
Usually you do not succumb to this leftist sleight of hand, but you have done so here in your use of the term “scientific consensus” in the false way that leftists frequently do - some out of ignorance, some deliberately.
Professional and hobbyist gardeners who raise CO2 levels in greenhouses and grow-tents to increase yields and growth rates will tell you that in addition to the fertilization effect, higher CO2 levels also decrease the demand for water and thus not only save on resources but mitigate the other negative consequences of intense irrigation.
The reason is that in order for land plants to absorb CO2 from the air, they must open pores in their leaves which also allows moisture to escape, which must be replaced or the plant with wither, especially in hot and dry conditions. The higher the ambient levels of CO2, the tighter the plant can close the pores, and the less water it loses it producing the same amount of useful material. The tables illustrating this trade-off have been well- established and well-known for generations for every variety of plant in every combination of growing conditions, they are hardly secrets. And yet one rarely encounters any official analysis of climate change costs that appropriately weighs this benefit.
Hobbyist gardeners have been left out of the scientific consensus on climate change. Got it.
Terrible reading comprehension. Come on man, I literally put the word professional in front, to contrast the hobbyists from professional growers who run large commercial greenhouse operations. But while few people know the details of such large businesses, millions of people do indeed grow hobby quantities of plants in tents using co2 tanks or generators, and they are all intimately familiar with the same facts that the professionals and agricultural scientists know. It is of course the scientific consensus in horticulture that higher CO2 levels definitely increase yields while reducing water loss. It is the industry of producing reports that are all downside and no upside that have not caught up the agricultural consensus and the economic consensus.
"Every variety of plant in every combination of growing condition." This is your claim. But much less than 1% of agriculture is undertaken in these conditions and some types of agrictulture not at all. Further, evapotranspiration is not the principal way in many environments that water cycles through the system, rather it is evaporation.
Nitpicking. I suggest a Google Scholar search on the topic. It is a very well-researched topic in Ag Science.
https://scholar.google.com/scholar?hl=en&as_sdt=0%2C14&q=CO2+crop+yields+greenhouse&btnG=
There have been extensive experiments on the relation between CO2 and yield, including indoor experiments, open field experiments, even one that looked at random variations in CO2 concentration across the US correlated with local yield data. They differ in how strong they find the relation to be but the general relation is consistent and well established. Increased CO2 concentration raises yields for C3 plants, reduces water requirements for both C3 and C4.
For you to invoke the phrase “scientific consenuss in response to the above demonstrates that you fail to understand that while there is a scientific consensus that the climate is warming, and that human activity is a major component, in fact there is *no* scientific consensus that this is an existential risk, nor on the public policy prescriptions leftists like yourself worship.
I think it is a mistake to think about climate change as a scientific problem. It is actually an economics problem.
If we are to be endangered by climate change, what that means is that people's standards of living in the future will be reduced over what they would be if there were no climate change. Those who favor high climate spending believe that by spending more today that will save future generations a much greater expense protecting themselves from having to build giant sea walls to protect coastal cities, etc.
True, living standards will be higher in the future if those living then don't have those heavy expenses. But living standards are not a function only of one's necessary expenses, they also depend on one's income. There is an implied assumption behind all climate change spending that it will not have any effects on future incomes. That is false.
Why do living standards rise over time? Only one thing - rising human productivity, which is almost entirely a function of savings (income we don't consume) invested successfully in things that raise productivity--R&D and better technology, capital goods and processes. But the purpose of climate change spending is not to raise productivity, it is to reduce our carbon dioxide emissions. Those are not the same thing.
We can concede that alarmist climate change models are correct, if we want to avoid scientific arguments that are over most people's heads, and still argue that the world will end up worse off by even moderate climate change spending, because it diverts business investment from its traditional goal of raising productivity and thus incomes toward instead cutting down on CO2.
The amount saved and invested is a small percentage of our incomes as is, especially with so many governments dissaving by borrowing to consume. Diverting most investment away from trying to enhance productivity will doom most economic progress, with possibly dire political and social consequences that endanger us more than the climate might.
Minor quibble.
"If we are to be endangered by climate change, what that means is that people's standards of living in the future will be reduced over what they would be if there were no climate change."
That "endangered" assumes no upside, or that upsides and downsides can be accurately measured and downsides are greater.
Two examples of upside: increased CO2 means more plant life, and warm climates kill far fewer people than cold climates.
Personally, I have zero faith in the ability to predict climate 75 years from now, and measuring the unpredictable upsides and downsides is just a joke.
I agree, but lack even the pretense of scientific knowledge enough to let me defend that argument. My point is that even if everything bad they say will happen to us because of climate change does happen, we would likely be able to handle all those things if we were a very rich society with high incomes. To the extent that directing R&D toward reducing CO2 rather than increasing productivity, we will be a much poorer society because our incomes will be much lower and be worse off even if our climate mitigation expenses are somewhat lower as a result.
In my book I pointed out that income per capital has risen by about 2%/year since the data series began in 1929. If by paying scientists and engineers to work on reducing CO2 emissions rather than working on increasing productivity, that reduces our income growth to about 1%/year, then people fifty years from now will have substantially lower incomes than otherwise, and it is unlikely that any reduced climate mitigation costs then could come close to making up the difference. IOW, we will be much worse off, even if we do a good job of reducing CO2 emissions. And it is far from clear that the subsidies and mandates will come close to accomplishing their ostensible goals.
I agree with you.
Every argument other than “existential risk” for leftist public policy prescriptions on climate is preposterously bad economics, even if the sign DF notes were known, and the magnitude were approximately known.
And not only is there no scientific consensus at all on “existential risk”, most of the leftists who themselves push their “climate change” policies oppose nuclear energy - which of course should not merely not be opposed but should be actively pushed as by far the best short and medium term way to address something that is an existential risk.
Which is a huge part of why I say almost all “climate change” advocacy is primarily political.
There are two reasons I don't believe the "climate crisis" is any such thing.
1. The proponents have lied too often, committed too much fraud, and failed every prediction (polar bears going extinct, no more snow) for me to trust anything they say. People with the truth on their side simply do not need to resort to lies and fraud.
2. If I thought the climate crisis was an existential threat in 10 years, I would do everything possible to push for nuclear power. Nothing else could possibly be implemented fast enough. Yet they don't. Ergo, they don't believe their own claims. Ergo, I don't either.
One need not know much at all about any field to detect those two flaws. When they tell me to trust the experts, I remember that "expert" comes from the Greek X for unknown and "spurt" for a little drip under pressure.
Where is your evidence that credible scientists have a consensus on polar bear extinction and the disappearance of snow from the world?
I said "proponents", not "credible scientists", which is too subjective to have any meaning. "Consensus" has also been bandied about too much to have any meaning.
Here: https://extinctionclock.org/
Very first entry predicts extinction of emperor penguins by 2100.
18 May 1972: From The Tuscaloosa News, Washington (AP), quote: "Arctic specialist Bernt Balchen says a general warming trend over the North Pole is melting the polar ice cap and may produce an ice-free Arctic Ocean by the year 2,000".
Of course, by definition all failed past predictions are no longer credible, and all future predictions are untested. So that may not be good enough evidence for you.
I don't think I understand your argument that spending on mitigating climate change reduces our productivity. Doesn't spending on climate change, in addition to the long-term cost avoidance that you cited, also push productivity forward? Development of clean energy technologies, energy efficiency technologies, and electric vehicles all seem like they enhance productivity. What is the evidence that resources that are currently being spent on mitigating climate change would otherwise be spent in such a way as to advance productivity more than this? I am not saying it would not, I am simply saying I don't see the evidence that it would.
That might be true, but only in the cases where the spending does improve productivity, as opposed to say meeting arbitrary and useless standards or attempting to solve a problem that doesn’t exist.
By way of analogy, say I want to improve the efficiency of my house energy wise. I can spend basically all the money I will ever have on that, but the net productivity side is not guaranteed for every dollar. Maybe I put more insulation in the attic, and that saves on air conditioning, but I probably shouldn’t spend so much I fill the entire attic to the rafters. Likewise, some spray foam might help seal cracks, but I could blow a lot of foam into the basement and not improve things at all.
Interesting analogy, but it doesn’t prove climate mitigation spending reduces overall productivity. Do you have evidence that the net effect is negative, or are you just arguing some projects are wasteful?
I was trying to explain the argument, not prove it. Spending on X does not necessarily improve productivity, regardless of what X is. It can even lower productivity. So if one wants to claim that spending on X will increase productivity, that needs to be shown and not assumed. (I would argue further that the burden of proof is on showing that it increases productivity on the basis that improving productivity is really hard, so most spending will not increase productivity.)
I was responding to Rick Teller's argument that climate change mitigation spending is reducing productivity. He presented no evidence to back his assertion. I noted that there is some evidence that climate change mitigation spending does increase productivity and requested a counterpoint argument. I infer, from your statement that you should not assume spending on X will increase (or, presumably decrease) productivity, that you also agree that Rick's argument lacks proof.
I find that both the left and the right consistently put forth specious claims with little evidentiary support. While I don't always agree with Professor Friedman, I appreciate that he attempts to provide support for the positions he takes.
Sorry, minor correction: I did read Rick's original argument; I thought you were referring to the other posts in this threads that I assumed you had meant to respond to instead of mine.
Rick's argument is that businesses by default seek to improve productivity by whatever means possible, and so if they have to be forced to spend money on X, then X must not improve productivity as much as the things they would rather spend on, or else they would be spending on it anyway. In other words, the presumption should be, absent evidence to the contrary, that spending on "clean energy" and electric vehicles should not be expected to improve productivity. I leave out energy efficiency because businesses do actively pursue that, although perhaps not so much as regulators think they should.
I think you will find you responded to me :)
I have not read Rick's argument, but rather am pointing out that there is no a priory reason to assume spending increases productivity, and indeed there is reason to presume it decreases it until shown otherwise. That's all.
IANAE but I'd say opportunity costs matter. When government forces spending resources on unnecessary projects, it diverts those resources from more worthy projects. Coerced projects are the least useful almost by definition, since if they had been useful, coercion would not have been necessary.
"Coerced projects are the least useful almost by definition, since if they had been useful, coercion would not have been necessary."
This is a very broad and rather bold statement.
If you believe that an unrestricted free market is the most efficient way to allocate resources, you are probably overlooking externalities that pricing ignores. But calling any kind of rule or regulation "coercion" oversimplifies how policies can fix market failures.
While IAANAE, and I agree that coerced projects may not always be the "most useful" (whatever this means) use of resources, that is true of almost all projects, coerced or not. But to go further and assert that coerced projects are the least useful assumes that the coerced project must be so nearsighted as to be completely devoid of benefit. Do you think electrification or the space program were the least useful use of the resources they required?
Are you able to clarify how this relates to spending to mitigate climate change? Governments have been imposing regulations, taxes, and providing incentives to promote a "green" agenda. By "coerced projects" are you referring to the development of electric cars and advanced battery technology? Are you referring to the plethora of markets created to develop energy efficiency technologies? Are you referring to the vast number of renewable energy technologies being developed?
I am an economist, and you are misusing these concepts.
You point out externalities in markets, but ignore externalities in government projects and regulations and government failures.
Coercion is precisely the word for government action. Sometimes coercion is the least bad option, but that is the mechanism by which governments function.
If we assume halfway rational actors, the chosen projects will generally be more efficient than those that require coercion to do. While it is true that sometimes people are wrong, what choices people making freely are almost always better than the choices they must be forced into when the measurement is their own interest.
Regarding "Are you able to clarify how this relates to spending to mitigate climate change? Governments have been imposing regulations, taxes, and providing incentives to promote a "green" agenda. By "coerced projects" are you referring to the development of electric cars and advanced battery technology? Are you referring to the plethora of markets created to develop energy efficiency technologies? Are you referring to the vast number of renewable energy technologies being developed?" Yes- one would be correct to presume that if people won't spend their own money on these projects but instead government has to take money that would be spent elsewhere and invest it in those places that people generally do not believe those are efficient uses of capital.
Yes, I neglected to mention that government projects also create externalities, but this does not negate my contention that government policy can mitigate market failures.
I am not sure what a "halfway rational actor" is. You are making a general statement that private actors will engage in projects that are "generally more efficient than those that require coercion to do." But, when we are talking specifics, namely, the numerous regulations, taxes, and incentives of the green agenda, what is your evidence that, absent these policies, the applied capital would have resulted in greater productivity gains in other projects?
As I am not an economist and I probably have an overly simplistic view of things, I think companies are generally motivated to pursue projects that will bring the greatest returns (generally monetary) to them in the short term. Investing in increasing productivity may, but also may not, result in the greatest short-term returns. Capital intensive projects that require long-term development, even though they may result in greater productivity gains, and a greater IRR (or is it MIRR?) are less likely to be pursued because of the long-term nature of the returns.
Some examples of this are the space program, which, I believe, advanced technology and productivity significantly, and cost-effectively and the 2002 mandate for TVs to incorporate digital tuners by 2007--which the industry strongly opposed, claiming it would add hundreds of dollars to the cost of each TV.
I don't believe that ALL government interventions (or if you want to call it 'coercion') are more efficient than the market and I also don't believe that ALL government interventions are less efficient than the market. Do you disagree?
So, the question is whether green interventions improve or decrease productivity? I think it would be more informative to argue for or against specific interventions with either empirical data or at least some intervention-specific arguments (e.g., I believe the government's developing/building/selling electric car "coercion" is rapidly advancing the technology of self-driving vehicles, which, I believe, is a significant productivity enhancer.)
I am not an economist. I don't know the Econ definition of externality, nor understand Pigou taxes. I've probably even got that little bit of jargon wrong.
But I take a real dim view of most justifications for government collective coercion. Take pollution, for example.
* If it's harmful, then it's measurable and traceable back to its origin, and ought to be prosecutable by its victims. Governments and cronies don't like this. A book on the history of New York City oysters, details of which I have forgotten but may be "The Big Oyster" by Mark Kulansky, tells of New York City sniffer squads, from the 1800s into the 1900s, tracking down pollution sources, and forensic analysts of the late 1800s tracking down pollution, such as soot on clothes drying outside, to show who to sue. This individual responsibility began to be outlawed by courts and legislatures on the grounds it did not take the public good into account; it was up to the government to decide how much pollution the nation could tolerate, and woe betide any individual who thought otherwise (Supreme Court of Georgia, Holman v Athens Empire Laundry Co., 1919: "The pollution of the air, so far as reasonably necessary to the enjoyment of life and indispensable to the progress of society, is not actionable").
* Victim prosecution and losers pays solve all sorts of problems. Third party prosecution, such as by governments, creates problems. When authority exceeds accountability, you have corruption. When accountability exceeds authority, you have scapegoats.
Coercion is not a mystery. Can the government jail you upon threat of death for not obeying their diktat? That's coercion.
I trust markets a thousand times more than I trust governments. And frankly, I don't care if a few fat cats get fat from providing what customers want. Bezos, Musk, Zuckenberg, Ellison, Gates, I despise and applaud them all in varying degrees, but there's not a single one deserves to be investigated by the government merely for building huge successful companies. They did so by satisfying customers, and in free markets, customers are king. All their companies will probably be as forgotten in 20 years as Alta Vista and MySpace are today.
Many years ago, I got to wondering what all the hubbub was about The Fed, and began exploring its history. The Panic of 1907 had a lot to do with creating the Fed, and the Fed didn't solve any of the problems which caused the Panic of 1907. Looking at its causes led to previous Panics and their causes and "fixes". To make a long story short, I concluded that government has caused far more problems than they've fixed. Governments murdered 100 million civilians in the 20th century, not including wars. The Mafia, drug cartels, and robber barons haven't come close.
Social and political problems are caused by governments too often to waste time in the few caused by individual bad actors, who are usually government cronies anyway, and whose victims are forbidden from prosecuting them by governments.
If our uncertainty about the net effects of climate change is so great that we can't even determine the sign, we certainly shouldn't be spending resources trying to change it.
To justify large expenditures, we'd need to know that the sign is negative and the effect is large.
Public statements by climate scientists leave out more than they keep in. Example, AR6, the 6th assessment report which was released in approved form in early 2022 had these three things to say about recent trends in floods:
1. We don’t know from observations whether floods have increased or decreased globally in the recent past. We'll have to try and infer it from other lines of evidence.
2. Changes in heavy rainfall suggest that floods might have got worse.
3. Changes in peak streamflow in rivers and waterways suggest that floods might have got better.
Only #2 made it into the executive summary. And by the time it makes it into the press release it’s a racing certainty.
Warning - always read the small print.
TS.C.4.5 Flood risks and societal damages are projected to
increase with every increment of global warming (medium
confidence). The projected increase in precipitation intensity (high
confidence) will increase rain-generated local flooding (medium
confidence). Direct flood damage is projected to increase by four to five
times at 4°C compared to 1.5°C (medium confidence). A higher sea level
with storm surge further inland may create more severe coastal flooding
(high confidence). Projected intensifications of the hydrological cycle
pose increasing risks, including potential doubling of flood risk and
1.2- to 1.8-fold increase in GDP loss due to flooding between 1.5°C and
3°C (medium confidence). Projected increase in heavy rainfall events
at all levels of warming in many regions in Africa will cause increasing
exposure to pluvial and riverine flooding (high confidence), with
expected human displacement increasing 200% for 1.6°C and 600%
for 2.6°C. A 1.5°C increase would result in an increase of 100–200%
in the population affected by floods in Colombia, Brazil and Argentina,
300% in Ecuador and 400% in Peru (medium confidence). In Europe,
above 3°C global warming level, the costs of damage and people
affected by precipitation and river flooding may double. {4.4.1, 4.4.4,
4.5.4, 4.5.5, 6.2.2, 7.3.1, Box 4.1, Box 4.3, 9.5.3, 9.5.4, 9.5.5, 9.5.6,
9.5.7, 9.7.2, 9.9.4, 10.4.6, Box 10.2, Box 11.4, 12.3, 13.2.1, 13.2.2,
13.6.2, 13.10.2, Box 13.1, 14.2.2, 14.5.3, CCP2.2, CWGB URBAN}
Do you think there are phenomena in economics where a similar effect has occurred?
Yes.
Details, please, details! :-)
The biggest example that occurs to me is analyzing what government should do on the implicit assumption of a philosopher king government, the state assumed to take the actions the economist thought it ought to take — the mistake corrected by Public Choice theory. That was very much the orthodoxy. Probably 1960's Keynesianism qualifies as well.
Thank you so much.
You are certainly correct about Public Choice theory. But the philosopher king assumption is so, so, so ... nice! We did mean so well. I suppose some climatologists mean well, but I'm sure not all. Philosopher king was not a means to destroy freedom and capitalism, but climatology is.
I'm sure you are correct about 1960's Keynesianism, too. I personally never had the problem because I was blessed with a truly horrible undergraduate textbook in the subject, and a truly great graduate course in the subject. Good textbooks did come out.
I've not seriously followed Macro, but I see primitive Keynsianism in the newspapers, on the Left, and in Britain. Public Choice has hardly been engaged with in the newspapers, on the Left, or in Britain.
So, we're still shaded, though surely not as much a climatology.
David, in the final paragraph, you write --
"To see how a mistaken consensus could be maintained imagine, very improbably, that my arguments convince Greenstone or Duffy that there is no good reason to expect climate change to have net bad effects and he publishes that conclusion. He would be converted in the eyes of friends and colleagues from a respectable academic to the climate equivalent of a biologist who rejects evolution, a nut case, a “denier,” would suffer very large costs, social and professional. It is prudent to avoid pursuing lines of thought or research that might lead to such consequences."
That is exactly what happened to Judith Curry.
Judith Curry is an American climatologist and former chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology. She has been a prominent figure in discussions about climate change, known for her nuanced and sometimes contrarian views.
She has been vilified and turned into a pariah. John Stossel interviewed her here : The FULL Judith Curry Interview: Climate Scientist Says World Won't End https://youtu.be/U0PQ1cOlCJI?si=8eEnxkaTbWjBzou1
...Any substantial change has some negative effects; to argue for government action to prevent a change you need to show that the net effect is negative, that costs are greater than benefits...
And you also have to show that the costs of mitigation are low enough to at least balance the improvements. I think this is a very high bar.
It seems outrageous to me that Govt can claim these sweeping powers with this rationale. I can think of a multitude of counterarguments to add to David's, but how about these additional:
1. Sulfur (lack thereof) in the atmosphere is an incredibly clear causation to global warming, much more so than CO2. Yet the govt is not just permitting that "harm" to be done, but mandating it.
2. USA has been flat or reducing emissions, and as such we are irrelevant as a causal factor for CO2-based warming. There is no argument to be made that sweeping powers (limited to the USA) are necessary to address global warming, because that's not a possible outcome.
3. Extreme weather -- The news always pins events on global warming, but I wasn't aware that it was scientifically valid. Certainly it's invalid to pin the California fires on Global warming. And again - warming has been mild until the last 2 years, DUE TO THE SULFUR
The whole thing (bad thinking) drives me up the wall, especially from the "trust the science" crowd.
Let's conduct a thought experiment, rather than getting into the weeds of climatology, measurement bias, the proven weakness and inaccuracy of climate change models, the actual effects of CO2, the irrefutable fact that climate experts have provided us with inaccurate predictions of catastrophe for the past 40 years, etc.
We'll go to "opposite world," where the claims are that global temperatures are falling, winter temperatures are dropping, summer growth season is shortening, blizzards and the damage they cause are intensifying,, ice is growing in the polar regions affecting global ocean currents, and "experts" tell us that we are in danger of another "ice age." Oh wait, some of that actually happened in the 1970s, ... whatever.
But back to opposite world and the coming ice age. Would today's experts suggest that we increase CO2 production to raise temps? Would they pass legislation that outlawed any attempt to use alternative ("clean") energy sources? Would they mandate the elimination of EVs by 2035? Would they allocation billions in federal funds to raise global temps? Would some activists suggest that countries producing low levels of CO2 transfer funds to countries producing more CO2 (to help raise temps)? All of those things seem crazy, but dropping temps are a "threat to future generations," aren't they? Remember, we're in opposite world, so it's likely that they would answer YES to my questions—to "save the planet," don't you know.
Whether we're in our current reality or in opposite world, it might be a better idea to proceed more thoughtfully and slowly, eschewing the very unscientific notion that "consensus" in science means the truth is known (it does NOT), that treating a complex multi-parameteric problem with religious intensity is necessarily a rational approach, or that hysteria, driven by political viewpoint, is a produ ctive way to make wide-ranging decisions that have significant unintended consequences.
'There is no mention of the fact that human land use at present is limited by cold, not heat,...'
I have seen claims that the Sahara is expanding southwards due to global warming. If true, this is presumably one place where human land use is limited or even reduced by heat?
The Sahara is hot, but less hot than some areas, including some in Africa, that are densely populated. It's lack of population is a combined effect of heat and lack of water.
If true, of course that would be a cost of getting warmer. But every report I have seen says the Earth is greening, adding more green (plant life, not eco warriors) cover and shrinking the Sahara.
https://wattsupwiththat.com/2023/11/12/sahara-expert-says-desert-shrinking-calls-alarmist-tipping-points-complete-nonsense/
Interesting. The quoted scientist only comments on the eastern Sahara, though. His conclusion may or may not be true for western Sahara, too.
That might well be, but I recall the Sahara was getting bigger back when global cooling was the fear. Then again I was pretty tiny, so maybe I am mixing memories a bit on the timeline.
It is worth noting though that the Sahara spreading a degree of latitude south would change a tiny amount of land compared to the arctic circle moving north by a degree of latitude. The Northern landmasses are immense.
Yes, I agree that the net effect of global warming is probably more arable land, not less. But I am not convinced that there is no loss of arable land at all due to higher temperatures.
The northern landmasses may look immense on a map, but they are less immense if you look at a globe. The distortion of a map increases with longitude. For instance, Greenland is actually smaller than Algeria but usually looks much bigger on a map.
If you read the piece of mine I linked to, you will find an estimate for loss of land from rising sea level. There might well be places where climate change makes land less useful, but what reason is there to think that, even if we ignore the shift of climate contours towards the poles, there will be more places made worse by the change than better? One of the predictions is increased rainfall, which should make places less dry. It isn't as if the present climate was designed for our benefit.
Just to be clear, I am not arguing that more places would be made worse than better. On the contrary, I agree with you that more places would be made better than worse. My only point - on which I see now that we are also in agreement - is that some places will be worse off, even if the overall effect for the world is positive.
I am not saying that there is not arable land lost, and I don't know that anyone else here is either.
Understood on the projection distortion of maps, but the land mass of North America, Asia and bits of Europe that are above the Arctic Circle are much larger than just Greenland, right? There is very little ocean between them, relatively speaking.
I don't think they need to establish that climate change is net negative for the purposes of the statute, just that it creates a risk of harm to public health or welfare. Rising temperatures are likely to do that somewhere (eg. heatstroke deaths in Arizona, fires in California), regardless of whether doubled crop yields end world hunger and Alaska becomes inhabitable.
Because you are not an expert on this and don't seem to want to bother to read AR6, run it through an LLM and see if it can answer your question on net negative effects of climate change.
“Hence to argue against such policies one does not, as Greenstone and Duffy assert, have to claim that the negative effects do not exist, only that they are at least balanced by positive effects.”
“ What struck me about the Axios story was that neither the author nor the academics quoted appeared to have thought about that question”
Due respect, but you are off base here, because you assume - either implicitly or explicitly -neutrally political good faith on the topic.
(Most) Leftists argue for such policies because it serves their political interest. Not quite “Period”. But primarily. And SURELY for the press writing articles such as these.
On a different, though related, point:
The “scientific consensus” is solely that the planet is warming and that human activity is a major component of that warming.
There is in fact NOT a scientific consensus that climate change is “bad”. Even as I don’t deny for a second that the large majority of the scientists who have gone into the field claim that it is bad and advocate for policies to combat it.
Usually you do not succumb to this leftist sleight of hand, but you have done so here in your use of the term “scientific consensus” in the false way that leftists frequently do - some out of ignorance, some deliberately.