Monday, September 05, 2011

What is Wrong with Global Warming Anyway?

The argument for large and expensive efforts to prevent or reduce global warming has three parts, in principle separable: Global temperature is trending up, the reason is human activity, and the consequences of the trend continuing are very bad. Almost all arguments, pro and con, focus on the first two. The third, although necessary to support the conclusion, is for the most part ignored by both sides.

The usual argument to show that an increase in global temperatures by a few degrees centigrade over the next century would be a catastrophe, or at least a very bad thing, consists of pointing out specific bad effects: rising  sea level increasing the risk of flooding in very low lying areas, rising temperature making particular areas less suited to growing the crops they now grow. But an increase in global temperature would also have good effects, as should be obvious to anyone who has ever spent a winter in Chicago, not to mention Alaska or Siberia. The question is not whether there are any bad effects but whether there are net bad effects, whether the increased risk of flooding in Bangladesh does or does not outweigh the opening of a sea route north of Asia and the increase in the habitable area of Canada and Siberia.

The answer, I think, is that nobody knows if the net effects would be good or bad, and probably nobody can know. We are talking, after all, about effects across the world over a century. How accurately could somebody in 1900 have predicted what would matter to human life in 2000? What reason do we have to think we can do better?

Should we, for instance, assume that Bangladesh will still be a poor country a century hence, or that it will by then have followed the path blazed by South Korea, Taiwan, Singapore and Hong Kong—and so be in a position to dike its coast, as Holland did several centuries ago, or move housing some miles further inland, at a cost that can be paid out of petty change? Should we assume that population increase makes agricultural land more valuable and the expansion of the area over which crops can be grown more important, or that improvements in crop yield make it less? While there may be people who believe that they know the answer to such questions, the numbers required to justify such belief are at best educated guesses, in most cases closer to pure invention. Someone who wants to prove that global warming is bad can make high estimates for the costs, low estimates for the benefits, and so prove his case to his own satisfaction. Someone with the opposite agenda can reverse the process and prove his case equally well.

If we cannot calculate in any detail what the actual consequences of global warming and associated costs and benefits will be, an alternative is to ask whether we have any reason to expect, a priori, that costs will be larger than benefits. There are, I think, two answers.

The first is that any change, whether warming or cooling, is presumptively bad, because current human activity is optimized against current conditions. Farmers grow crops suited to the climate where they are growing them; a change in climate will require a costly change in what they grow and how they grow it. Houses are designed for the climate they are built in and located in places not expected, under current circumstances, to flood. Putting it in economic terms, we have born sunk costs based on the current environment, and a change in that environment will eliminate some of the quasi-rents that we expected as the return for those costs.

This is a real argument against rapid change. But the global warming controversy involves changes over not a year or a decade  but a century. Over a century, most farmers will change the crop they find it most profitable to grow multiple times; if average temperatures are trending up, those changes will include a shift towards crops better suited to slightly warmer weather. Over a century, most houses will be torn down and replaced; if sea level is rising, houses currently built on low lying coastal ground will be rebuilt a little farther inland—not much farther if we are talking, as the IPCC estimates suggest we should be, about a rise of a foot or two. Hence the presumption that change is bad is a very weak one for changes as slow as those we have good reason to expect from global warming.

It is hard to see any other reason to expect gobal warming to make us, on net, worse off. The earth and its climate were not, after all, designed for our convenience, so there is no good reason to believe that their current state is optimal for us. It is true that our species evolved to survive under then existing climatic conditions but, over the period for which humans have existed, climate has varied by considerably more than the changes being predicted for global warming. And, for the past many thousands of years, humans have lived and prospered over a range of climates much larger than the range that we expect the climate at any particular location to change by.

If we have no good reason to believe that humans will be substantially worse off after global warming than before, we have no good reason to believe that it is worth bearing sizable costs to prevent global warming.

Readers who reject this conclusion are invited to offer reasons why we should expect the negative effects of global warming to outweigh the positive. Readers on the other side, inclined to post comments attacking me for being so credulous as to accept the reality of anthropogenic global warming, are free to do so but should not expect any response from me, since that is not the argument I am at the moment interested in having.

66 comments:

Eric Goldman said...

David, this isn't totally responsive to your inquiry, but I do note that rapid climate change will likely lead to significant species extinction because current species won't have time to adapt and new species won't immediately evolve to occupy the new niche.

Obviously it's impossible to quantify the effect of any one species' loss. If anything, this reinforces that some effects are unknowable in advance.

At the same time, it's not clear to me that technological innovation could remediate any ecosystem collapses due to species extinction. (E.g., if there were a massive worldwide collapse of bees, there's no obvious way to perform pollination in non-human-managed ecosystems). Thus, I would put species extinction in the category of an unknowable bad without any obvious countervailing benefits.

Miko said...

As long as we're identifying separable portions of the argument, I'd further split the third step you identify into "the changes are (on net) bad" and "the costs of preventing the changes are small compared to the costs of the changes."

I'm not entirely convinced by your argument for "moving housing" to counteract rising sea levels. The important factor here is not the vertical rise but the much-more-difficult-to-measure horizontal change. E.g., in particularly flat areas, are entire properties going to disappear? Even in areas with only minor horizontal losses, this sounds like a monstrous thing to coordinate, as the land the house would be moving into might fall onto a neighbor's property, potentially creating a domino effect reaching far inland. More likely, waterfront property will just get smaller.

@Eric: Thus, I would put species extinction in the category of an unknowable bad without any obvious countervailing benefits.

Won't it be its own countervailing benefit? Bees dying may be bad, but flies and mosquitoes dying sounds like a positive to me.

I do note that rapid climate change will likely lead to significant species extinction because current species won't have time to adapt and new species won't immediately evolve to occupy the new niche.

Evolution isn't the only mechanism for such adaptation. If humans understood the necessary changes, we could genetically engineer them in.

Randall Parker said...

David, There are non-temperature-related categories of change due to higher CO2:

- Oceans become more acidic as more CO2 dissolves into the ocean.

- Higher CO2 enables some plants to grow using less water.

Warming has a number of potential effects. Here a few:

- Loss of land to rising waters.

- Shift of rains away from settled farming areas and toward less populated areas.

- Areas become too hot to support human life.

- Longer growing seasons.

What I think is most important to this debate: Fairness. While at a macro level benefits might equal or exceed costs that's not true for every individual. Whole countries could pay a big price while other countries benefit. The countries that benefit will be strongly disinclined to help the countries that are harmed by the warming and other changes.

Another point: Anthropogenic Global Warming (AGW) is a symptom of the scale of humanity's impact on the ecosystem of the planet. I think it is unfortunate that AGW gets so much attention because other impacts might be more important in the long run.

Randall Parker said...

One more point: We can do climate engineering against warming if the costs of warming will be too great. But I do not yet see a way we can prevent pH change of the oceans.

Sascha said...

David,
all I can give you is another educated guess, but i would assume that by rising sea-levels we would get a net loss of habitable land.

And even if the land that gets available due to the melting of ice (for instance Antarctica) or the change in temperature (for instance Siberia or Greenland) would be as big or even bigger than the land lost due to the rise of sea levels, it would most like take to long to establish civilization in these places to balance the loss in the others.

David Friedman said...

"What I think is most important to this debate: Fairness. While at a macro level benefits might equal or exceed costs that's not true for every individual. Whole countries could pay a big price while other countries benefit."

And it seems fair to you that countries should be expected to bear sizable costs--keeping down their use of fossil fuel, say--in order to prevent changes that would benefit themselves? Isn't there a conservative assumption here that's hard to justify--that a change that helps A and hurts B is bad, but preventing that change—thus, on net, hurting A and helping B—is good?

Why is the status quo privileged, so privileged that we are obliged to bear large net costs in order to preserve it? And if it is privileged, why is it privileged only with regard to climate change—why doesn't the same argument imply that any change, say in the terms of international trade, that makes some people better off and others worse off, ought to be prevented?

Einer said...

I think the problem is exactly that we don't really know, what to expect. The earth-climate is a highly complex system and we know too little about it, to reliable predict, what will happen, if we change this variable or that one by this value... We really don't even know if the pessimistic estimation of what will happen is an understatement.

Let me put it this way: Assume you sit in an nuclear reactor and you only know the basics of how it works. And since you are not an expert on radiation, your not exactly sure, what happens, if the core should melt: If people would die or if just the radishes will grow bigger. But you notice that if you spin that knob the reactor temperature rises and you get more energy. That's good. And if try another knob it even gets better! The extra energy is useful for a lot of things - it generates benefit. You might say: "Well, what do I know, maybe the reactor will blow and maybe not. What I do know is, that it would be an reduction in benefit if I don't turn that knob!" But exactly because we don't know, I'd call it irresponsible to do so.

On reactor safety we've got experts, who knows exactly how an reactor works, what happens if you spin that little knob, and what if you press that button. And we know a lot about the what damage a MCA does to the environment. Climate on the other hand is much more complex, and nobody knows what causes what. Still we are (metaphorical speaking) wildly spinning knobs and pondering what it will cost if something happens, that we know little about and if a possible damage might or might not outweigh the benefit.

If I was in the reactor, I'd leave the knobs alone, and spent my money on some highly educated scientists to learn how much energy I can safely extract and what the consequences are if something goes wrong. Then and only then I'd start pressing buttons.

Randall Parker said...

David, I doubt there is a God who has determined some master moral code that we all should adhere to. But to be more clear: I'm arguing that lots of those who advocate for reduced CO2 emissions are arguing against one group giving itself benefits at the expense of others.

Aside: What I find annoying about this debate is that I find reproduction as having far larger external costs and it is a cause of global warming. Yet advocacy for population growth control died out after the 1970s.

Picture the world with 1950 population levels. Far fewer people to flee from rising sea levels. Far fewer people to emit CO2. Far fewer people to compete for dwindling oil and assorted minerals. Far more land per person and so less impact from shifting rains or heating.

Terrence Chan said...

It's probable that there is some negative impact and cost of global warming. But it's not really whether global warming is good or bad, right? It's whether the alternative; namely, reducing CO2 emissions, is more costly or less costly to us overall. So any analysis of the bad things that would happen if the global temperature went up a few degrees would have to be weighed against the costs of doing something about it. So it's a matter of whether we think that curbing CO2 output now, with current technology, is better than trying to fix the effects later, with future technology.

Terrence Chan said...

In reading the comments I see that Miko already said what I had to say. My bad!

jdgalt said...

@Miko: As long as we're identifying separable portions of the argument, I'd further split the third step you identify into "the changes are (on net) bad" and "the costs of preventing the changes are small compared to the costs of the changes."

I'd split it up farther. One of the main alarmist arguments is that the costs will not be spread evenly but will fall mainly on poor countries (many of them small islands, like Kiribati, where Ban Ki-Moon today promised to continue the fight against climate change). If climate change does turn out to be real, I can see a good case for giving those people somewhere to go, perhaps even making sure they are allowed to stay a separate country. Various ways of doing this come to mind, including of course seasteading. :)

But the costs of preventing the changes also deserve further analysis, because I'm convinced there are much cheaper and better ways than giving up a lot of our wealth in the name of "reducing our carbon footprint" -- a plan I believe to be an end in itself for the "watermelons" who lead the environmental movement and the UN. If Benford's bargeload of iron filings won't do the job, Keith Henson's orbital mirrors or some other cheap and simple idea very likely will.

The important thing is not to panic. Because that's exactly what the bad guys want us to do.

Randall Parker said...

John David Galt makes a good point: don't panic. Pull out your Hitchhiker's Guide.

What I'd like to know about islands that could be submerged: What would it cost to bring in more topsoil to raise them up? Which islands are threatened and what is their surface area?

It occurred to me to ask this because Johnston Island (and Sand Island both of Johnston Atoll) was expanded by over a factor of 10 by the US military during the Cold War.

David Friedman said...

"What I find annoying about this debate is that I find reproduction as having far larger external costs and it is a cause of global warming."

The point I made in this post about the difficulty of estimating net costs is one that first occurred to me in the context of population issues. My first piece of published economics was a pamphlet written for the Population Council in which, among other things, I tried to estimate the net external cost of population increase:

http://www.daviddfriedman.com/Academic/Laissez-Faire_In_Popn/L_F_in_Population.html

I concluded that I not only could not reliably estimate the size of the external cost, I could not even tell its sign.

Obviously you think you can--but that suggests to me that you may not have tried to include in your calculation the positive effects of population increase.

Robin Hanson said...

It seems intuitively obvious to me that messing with the climate should increase the thickness of far tails of bad climate events. Of course this risk has to be weighed against ways in which faster/more growth would reduce the thickness of tails of other sorts of bad events.

philosofool said...

I don't actually get the argument.

Your basic claim is that we're in a position of extreme ignorance. But that just leaves us incapable of deciding. It does not in any way say anything about any particular course of action--except the course of action that tries to remove ignorance.

To put this point another way, you conclude "If we have no good reason to believe that humans will be substantially worse off after global warming than before, we have no good reason to believe that it is worth bearing sizable costs to prevent global warming." However, given what you say, you must equally admit that If we have no good reason to believe that humans will be substantially better off after global warming than before, we have no good reason to believe that it is not worth bearing sizable costs to prevent global warming.

Ignorance is no safe harbor for our antecedent preferences.

(For what it's worth, I think you're a little cavalier to say we don't know. Lots of people have tried to figure out the effects of global warming, including those creating costs to humans, and you just sort of tell us, without evidence, that none of those people have succeeded.)

Randall Parker said...

David, Whether new babies are an asset or liability depends on their capabilities and what they achieve.

Randall Parker said...

David, I'm not seeing signs of a faster rate of innovation as basically more human processing units come online as a result of advances in comm tech and globalization. I'm with Tyler Cowen in the view that important innovations appear to be coming less often, not more.

Of course, maybe without, say, more East Asian and Eastern European brains plugged into the world market economy we've have an even slower rate of innovation. But commodity prices make me think that globalization so far is a net liability for those already industrialized.

Milhouse said...

Is there a reason this post specifies font-size:small? I find it more difficult to read than your usual font.

Anonymous said...

"...you must equally admit that If we have no good reason to believe that humans will be substantially better off after global warming than before, we have no good reason to believe that it is not worth bearing sizable costs to prevent global warming."

If someone is going to claim problem X exists and the solution to problem X is solution Y then that person bears the burden of proof. Not the person making the claim that they are not convinced X is even a problem.

Example: Dubya says "Saddam has WMD's and that will lead to terrorist attacks in the US" (problem) and the solution is a military invasion. Dissenter A says, "Sure, Saddam has WMD's but no invasion is necessary because he wouldn't attack the US". Dissenter B says, "No invasion is necessary because Saddam doesn't even have WMD's".

Both philosofool and Dubya might say, "because we have no good reason to believe that Saddam won't attack the US with the WMD's he may or may not have, the US has no good reason not to invade Iraq".

"Lots of people have tried to figure out the effects of global warming, including those creating costs to humans, and you just sort of tell us, without evidence, that none of those people have succeeded."

Actually, every model that I know of that has made short-term predictions has been wrong (here is the latest). Can you point me to a model that has been shown to make accurate predictions without making inaccurate predicitons at the same time? If not, may I suggest it is you that is being cavalier with your assumption.

philosofool said...

"If someone is going to claim problem X exists and the solution to problem X is solution Y then that person bears the burden of proof. Not the person making the claim that they are not convinced X is even a problem."

Burden of proof? We're not trying to prove things, we're trying to chose the right action. We have two choices (roughly speaking), and we have to figure out which one is right. Talk about burden of proof just misses the point.

Phil said...

Wow, I guess the fact that humans can't breathe carbon dioxide does not matter to this author? When the carbon levels reach 450 ppm humans will have trouble breathing. We will be at 400 ppm before the end of 2012.

http://www.esrl.noaa.gov/gmd/ccgg/trends/

I'm sure the author thinks that may not be a bad thing as the world is overpopulated.

Marcel said...

Phil: When the carbon levels reach 450 ppm humans will have trouble breathing.

Really.

It took me about 40 seconds to find this: http://www.inspectapedia.com/hazmat/CO2gashaz.htm

In an indoor air test (in our laboratory) the detector found that the CO2 level was about 600ppm which is typical of indoor air and is an acceptable and safe level.

I guess they just don't make indoors like they used to...

Note when the breathing trouble starts:

Above 2%, carbon dioxide may cause a feeling of heaviness in the chest and/or more frequent and deeper respirations.

That's over 20,000 ppm. I guess Phil doesn't see much of a difference between 450 and 20,000... Phil, don't go shopping.

Alexandra Thorn said...

Shortest answer I can think of (in my own short time):

We do not know the range of habitats that are capable of supporting a stable human population. We do know that we are alive in the current environment.

We also know that the temperature highs we are talking about has not been experienced at any time in meaningful human history.

Who knows what dreams may come?

Hammerhead said...

A small bit of increase in mean global temperature in the next century would cause far less harm to humans than the onset of another ice age. Picture north america and europe covered in ice shields. Is someone imagining the earth's climate can continue in a perpetual stasis whose ideal is defined by some mean average temperature cherry-picked from an arbitrary previous point in time, e.g., 1850? The planet has a long sometimes violent and changing history and will likely continue with its positive (and negative) feedbacks most of which we don't understand very well in 2011.

Moron Watch said...

What a moronic piece of reasoning. I've written a response to this article here: http://moronwatch.blogspot.com/2011/09/moron-economist-david-friedman-and.html

Milhouse said...

We also know that the temperature highs we are talking about has not been experienced at any time in meaningful human history.

Huh? Not only have warmer temperatures been experienced within meaningful human history, they've been experienced within the past millennium. And yet we're all here.

jimbino said...

I think there is a fourth point to the argument: Why the hell should I, who has personally voted against breeding, be forced to give up present wealth and income for the sake of the breeders' grandchildren?

It's bad enough that I pay through the nose to support current breeders and their children, but the idea of being taxed for non-existent human brood drives me insane.

I subscribe to the philosophy of "Die Broke" and greatly resent having to buy into the breeders' philosophy and religion. My idea of a good environmental campaign is to develop a universal human birth control for the world's waters.

David Friedman said...

"However, given what you say, you must equally admit that If we have no good reason to believe that humans will be substantially better off after global warming than before, we have no good reason to believe that it is not worth bearing sizable costs to prevent global warming."

No. The conclusion would be that we have no good reason to believe that it is worth bearing sizable costs to insure global warming.

We know that bearing sizable costs is in itself bad. So it is worth doing only if we have reason to believe that it produces sizable benefits. If we don't know whether those costs will produce net benefits or net costs, which I am arguing is the case, then we don't have a reason to bear them.

Anonymous said...

A lot of people who used to laugh at the 'skeptics' are now hesitant themselves to say they believe in global warming because of the baggage that comes with it. Whether climate change is catastrophic or not really isn't the question, because even if it is, the proposed solutions of massive taxation and energy subsidies (which are associated with those who believe in global warming) will not solve the problem.

Bob Murphy said...

Dr. Friedman, you might want to skim my article in The Independent Review. I touch on this point specifically, and cite some research you might like.

Manicbeancounter said...

You make some good points here. I would like to put the positives of global warming into context and pointing the way to making the analysis of the consequences of global warming more rigorous.
The consequences of global warming may have positive and negative consequences. The severity of any consequence should be assessed according to three factors.
1. Magnitude – how large it will be. This can be over a number of dimensions. So a predicted worsening of hurricanes, for instance, might be in frequency, power and area.
2. Likelihood. The Probability of a forecast event it occurring.
3. Randomness. It is predicted the weather systems will become destabilised, so the weather will become the norm.
When extreme events are postulated, the magnitude that is most often over-stated is time. So sea levels are imagined to rise by a foot a year, not a century at the current rate (3.2mm per year is the best estimate). The rate of change is crucial here. Incremental changes over generational times scale we will not notice globally, as economic conditions change much more rapidly than this. Also there are unstated assumptions about the likelihood of the events. From an economic point of view, the potential costs can be many times over-stated by a combination of magnitude and likelihood. There are two main reasons to believe this is the case – adaptation and way-markers.
Adaptation is people changing to changed circumstances. The reason that living standards are over 30 times greater and the world population is more than 10 times greater than 300 years ago is than the human race cannot just adapt to changing conditions – in wealthy countries extreme weather events and failed harvests are hardly a problem. Look back to the 1960s and 1970s, the mainstream forecasts were for increasing poverty and starvation. With the exceptions where governments are extremely bad (North Korea, Zimbabwe) or there has been extensive conflict (Zaire), this has not been the case. But many of the prophesies of doom assume no adaptation at all. So literally, farmers will grow the same crops they always have, and people will not think of moving as the sea immerses their houses.
Way-markers are the signals of climate change happening now. Many of the extreme short-term forecasts have been falsified, or shown to be based on pseudo-science. Sea levels have failed to rise by 20 feet since 1990, and the Himalayan glaciers will not be gone by 2035. With these clear near-term failures, it is reasonable to say that more long-term extrapolations will be also unreliable.
On the other side, whilst individuals and communities are incapable of adapting to changes, the assumption is that Governments can fix anything at minimal cost. So, subject to a global agreement, CO2 can be constrained (according to the UK Stern Review) at one fifth to one twentieth of the likely costs of doing nothing. No allowance is made that government projects tend to overrun on costs and underperform on benefits, nor that the this degree of underperformance tends to proportionately rise with lack of planning, vagueness of objections, complexity of organisations involved and scale.
I have enlarged on this, with some appropriate links at my blog.
http://manicbeancounter.wordpress.com/2011/09/06/the-positives-of-global-warming-in-context/

Milhouse said...

If we have no good reason to believe that humans will be substantially better off after global warming than before, we have no good reason to believe that it is not worth bearing sizable costs to prevent global warming

You can bear whatever costs you like, but unless you can prove that the costs are necessary what gives you the right to force me to bear them? So long as you can't prove that it's at least more likely than not that my carbon-spewing ways are harming anybody, what gives you the right to force me to stop? Just because you're stronger than me?!

Anonymous said...

> houses currently built on low lying coastal ground will be rebuilt a little farther inland—not much farther if we are talking, as the IPCC estimates suggest we should be, about a rise of a foot or two

Tides. And there are other people further inland.

Nightrunner said...

David,

Let me give you an example. Madras metro area (http://en.wikipedia.org/wiki/Chennai) has 7.5 mil population and average elevation of 20ft. Assuming for first approximation a normal distribution of the population by elevation, the number of ppl living at 2ft elevation today is about 2% -> 150K. Plus descendants. That is just one city, for the whole south-east Asia the number is in the tens of millions. You look at this number and see a nice tidy resettlement program, I look at this number and see riots and misery for the refugees - if not a series of outright wars. Its nice to be an optimist - helps you sleep at night. But makes you wrong and sad once in a while.

David Friedman said...

"You look at this number and see a nice tidy resettlement program,"

No--I'm not imagining government solutions. I see people, over a century, changing where they live--as they have been doing, on a much more massive scale, over the past century.

Someone else mentions tides. We already have tides. A two foot rise in sea level means a two foot rise in high tide.

He also mentions that there are people living just inland. Of course there are. That doesn't mean that, over a century, housing patterns can't change, as they have been changing in the past. New housing gets built a little farther inland than it would have without global warming.

Nightrunner said...

> I see people, over a century, changing where they live--as they have been doing, on a much more massive scale, over the past century.

Quite a few people changed where they lived because they were forced out by famine and wars. You are right in that the housing patterns are bound to change to some extent. Your belief that they will necessarily change in a good way makes you double the optimist :)

Anonymous said...

It may be cheaper to resettle even several millions than to force the cut in production to limit CO2 release.

$9,000,000,000 Write Off said...

Let's not forget that we're living during the tail end of the Holocene interglacial period and the more ordinary glacial period may commence any century or millennium now.

When glaciers melt the newly unburdened land rises, offsetting in some unquantifiable way the rising seas.

Plus, most of the world's land mass is in North America, much of which is often-frozen wastelands.

How all this factors in with prior comments and other tidbits, I have no idea and I doubt anyone does.

$9,000,000,000 Write Off said...

Sorry, meant to say most of the world's land mass is in the northern latitudes, not in North America. Don't let me near any legislative power!

Anonymous said...

The Netherlands have 25% of their land below sea level. No one's mentioning simply building levies where a rising sea is a problem. It's cheap (comparatively) and a well-known engineering problem.

Daublin said...

It's a very good point, David, and I haven't seen any great arguments that global warming is obviously bad. Indeed, the most obvious effects of a few degrees of warmth are good.

The strongest argument I've seen is the one Eric gives in the first comment: maybe the rate of change is more important than the magnitude, and the rate of change will cause extinctions. However, if you believe this theory, you have to explain why we don't see mass extinctions with the larger regional changes that occur year to year.

After a lot of thought, I've come to stop viewing global warming as a problem that is itself driving people to want certain solutions. Instead, it is usually a rationalization for policies people already want. Once you look at it this way, you explain a lot of other mysteries, such as why most catastrophists ignore nuclear power.

The biggest mystery to me is why so many scientists and academics are happy to ignore the argument you make in this post. Where are our clear thinkers that rise above the fray?

Grant McDermott said...

There are three basic *economic* arguments for swift/decisive action against climate change. Trying to summarise them in crude soundbite format, according to their respective popularisers:

1) Ethics (The Stern Review)
2) Relative Prices (Sterner and Persson)
3) Uncertainty (Weitzman, Gollier)

Importantly, the first two above are based on fairly standard cost-benefit analysis approaches. The expected benefits of global warming (e.g. moderate agricultural gains in parts of the US) are weighed up against the expected costs (e.g. prolonged drought in central and southern Africa). In other words, the fact that warming *does* imply benefits to parts of the world, or within certain industries, is not unduly ignored. It is simply set against the potential negatives.

The key issue, however, lies not with the simple "net" result, but the way in which the flows of these net benefits/costs are weighted over time. That's right folks, the fundamental issue in climate change economics is the discount rate.

It is this discounting debate that really separates the "act now, act fast" side (e.g. Stern), from those that council "grow richer first, adapt or mitigate later" (e.g. Nordhaus). FWIW, I consider the relative prices argument -- related to the imperfect substitutability between manmade and natural goods -- to be one of the most compelling reasons for swift action against climate change... partly because it helps to abstract from the discount debate. You can read a bit more about these topics here and here, if you are interested.

The last argument that I mentioned above concerns "uncertainty" (Weitzman Gollier). This line of reasoning suggests that use of standard CBA approaches to weigh up the net costs/benefits of global warming is wholly inappropriate... due, in short, to fat-tail risk; i.e. low-probability, high impact. (For the Nassim Taleb fans out there, just think black swans). It's a inadequate analogy, but you can think about it as the type of logic that underpins any insurance decision. Some related comments on this issue here.

Milhouse said...

It puzzles me that people list malaria as one negative effect of any warming that might happen, as if malaria had something to do with warm weather, or with warm climates. Malaria isn't a problem in North America and Europe because it was exterminated, not because it's too cold!

neil craig said...

There is one way we can be effectively certain of a benefit. Increasing CO2 has a measured effect on plant growth
http://www.omafra.gov.on.ca/english/crops/facts/00-077.htm

This has already increased growth 25%, altho the rate of of increase is starting to tail off. This is highly beneficial to everything that eats food which includes not only us but the entire biosphere the "environmentalists" claim to care about.

Doc Merlin said...

Experimentally, the CO2 increase has increased crop yields by over 10%. This is enough to result in the effect of human CO2 production to be positive, by itself!

Anonymous said...

The coming global warming disaster will likely be combined with thermonuclear war and other enviromental catastrophes like deforestation, and the extinction of many species in the oceans and on land. Adding another billion, mostly poor people, to the planet will make matters much worse. Life is VERY fragile. You'll be dead in a few minutes if your breathing or heart stops. No one likes that fact, but it it is an essential fact. One should never forget were we came from. A Fuck.

As far as the temperature increasing "only a few degrees." That in itself is quite bad overall. The Artic and Antartic habitats are complete goners. As Asimov spoke and wrote about, the inhabitents of planet Earth can adapt to inevitable GRADUAL change. The problem is that the change invisioned will be rapid and catastrophic.

My blood boils when people without credentials talk about global warming. That is not at all good for my health. But, you are not concerned about one death except it be your own. You should be condemned for that "net" line of thinking as well.

neil craig said...

Absolutely, Armageddon real soon now.

And the Bizan shall be huge, and black, and the eyes thereof RED with the blood of living creatures! And the whore of Babylon shall ride forth on a grey headed serpant, and throughout the lands there shall be a great rubbing of parts. And the demon shall bear a nine bladed sword. Nine bladed! Not two, or five, or seven but NINE! Which he shall wield on all wretched sinners, sinners just like you, sir there. And the horns shall be on
the head;

Don't you just love anonymous ecofascists whose "blood boils" at those without credentials spouting off.

With thanks to Life of Brian

Doc Merlin said...

World agriculture production is 6% of world GDP. World GDP is about 60T dollars. So CO2 production has increased just the agriculture portion of world GDP by around half a trillion dollars a year. Thats a massive effect.

Milhouse said...

If a few degrees of warming were enough to make "the Artic and Antartic habitats" (wherever they are) into "complete goners", then how did they survive the Medieval Warm Period?

Milhouse said...

"anonymous", you don't seem to care about all the people who will be significantly poorer if trillions of dollars have to be poured down the hole of cutting CO2 emissions; you don't care about the waste of those resources, or the goods and services that people would have bought with them. You don't care about the people whose health will suffer, and who will die prematurely, since economic prosperity is the greatest factor in health. So why should we care about your blood pressure?

Anonymous said...

Merlin the Magician,

The people, and their heirs, who created the climate and other ecological disasters should be bankrupted as far as I'm concerned for their bad deeds that created these horrid externalities. Also, I would bankrupt people like you, who want to pass the problem on to their posterity, who did nothing to create this mess. I won't even go into the death of voiceless species that cohabit the planet, except to say that I hope that a nearly extinct rhinocerous charges you and tramples you, and people like you, to death.

Milhouse said...

Nice. Real nice.

1. There is no disaster.

2. Why do our descendants deserve any more than we choose to pass on to them? By what right does the world belong to them rather than to us? Do your children have a claim against you if you spend your money on yourself rather than saving it up so they can inherit it? If that argument doesn't work on the individual scale, why do you imagine it works any better on the global scale?

3. If you would bankrupt people like us, why do you imagine we care about your health?

4. I don't imagine a nearly extinct rhinoceros (note spelling) would be capable of charging anything. If it has the strength to charge a person then it's not nearly extinct, is it? Though why we should care about a rhino's health is beyond me. What good is it doing anyone?

Little GTO said...

Hi Milhouse

Nearly extinct means population size is nearly not enough to ensure continued breeding. To give a whimsical example: If Eve dies young, Adam is technically extinct, even if he is still young and healthy.

(P.S. I was unable to send this to you as an email since my hasty scan of your blogs turned up no obvious way to contact you.)

SoopahMan said...

The problem is the rapid change you acknowledge in your post. Global warming means more than a rise in sea level: It means more energy in the oceans and air, leading to more evaporation and wind. This leads to more weather: More hurricanes, monsoons, snow storms, floods, and tornadoes. It also forces many well-known climate areas to shift, historically - so speaking simplistically if 2 neighboring areas are tropics and desert, they may well swap. This is something that most large animals will not be able to adapt to, and will wipe them out. It's also much more costly in terms of the human cost than you might envision. Suppose that tropical area supports one nation and the desert another, and in 50 years their ideal environment is across each other's border? War. Suppose one nation completely loses its water supply in 4 decades due to climate shift.

I agree a more mild shift is survivable, and if not for man-made global warming we would experience just that. You simply underestimate the impacts of man-made rapid change. Humanity and small creatures will likely survive man-made climate change, but it could be very ugly.

There is also one final concern about runaway global warming: There is a theory that Mars had water until something happened - perhaps a severe period of volcanism - that lead to runaway global warming there. It's proven that global warming is spiking faster than it ever has compared to geological records. If we do nothing to curb it as you prescribe, and we allow it to warm into the unknown global temperatures that lead Mars to become a barren waterless planet, that is an unsurvivable proposition for humans and all but the most extreme and miniature life forms on earth - and possibly the end of life on this planet altogether. That may be 100 years out, but saying "Let's deal with it in 100 years" is clearly irresponsible.

Milhouse said...

Nearly extinct means population size is nearly not enough to ensure continued breeding. To give a whimsical example: If Eve dies young, Adam is technically extinct, even if he is still young and healthy.

Um, no. How is any individual's extinction hastened or delayed by the number of other creatures who share his species? A species may be near extinction when its numbers dwindle, but no member of that species is any closer to extinction than it would be if the species were as numerous and fecund as cane toads.

Richard Lewis said...

"Nasty, brutish, and short," characterized life in England before the industrial revolution. It still characterizes life in much of China, India, and almost all of Africa. These peoples are daily choosing the Western industrial model to rise out of grinding poverty. Fossil fuels provide the power, and will for a century. So if that choice results in global warming, we in the industrial West have no choice but to ADAPT! And effective adaptation can only be done with vigorous economies. Let us not commit economic suicide by "going green" when the result is foregone anyway.

Little GTO said...

Milhouse, you are correct and I was wrong. I mixed up "the capacity to breed and recover" with "extinction." Wikipedia's article on extinction convinced me I was wrong. I apologize.

David Friedman said...

"My blood boils when people without credentials talk about global warming."

What sort of credentials are you thinking of? The argument for holding down CO2 production in order to prevent global warming depends on at least three different and unrelated forms of expertise--climate science, statistics, and economics.

Are you arguing that nobody without suitable credentials in all three is qualified to talk about global warming? That eliminates pretty nearly everyone who does. If credentials in one of those fields are sufficient, then I qualify. No idea if you do.

As you might have noticed if you read my post, I'm not making claims about either climate science or statistics, merely accepting the standard claims made by those arguing for the position I'm arguing against. So my argument doesn't require expertise in either of those fields.

Randall Parker said...

David, Here's another thought: If you assume rising living standards in the now poor countries then the ability to adjust to climate will go up enormously.

Consider, natural disasters hit poorer countries far harder. More buildings fall down from earthquakes and hurricanes, poor cities have fewer flood defenses, and the people have less financial resources to draw on to tide them over when crops fail. If poor countries remain poor then changes that cause more severe weather events or rising waters are harder to deal with. But if living standards in, say, Bangladesh triple adaptation becomes more affordable and the worst that nature might throw out does less harm.

Though even if warming comes it is not clear that really means more hurricanes or severe rains. Depends on where you are.

Sea Fan said...

Have you read the hundreds (probably thousand by now) of papers referenced in the IPCC reports about the impacts of global warming of varying degrees and distributions?

It seems rather silly to dismiss intelligent people's lifetime work by saying "it's too complicated for me to understand so I'll just assume that no one knows and I'm right".

Milhouse said...

Sea Fan, have you read them? Can you say, from your own knowledge, how many independently verify their premises, and how many just assume that the story is true and go on from there to explore what consequences it would lead to? For that matter, how many of those papers would you say are by people smarter and more qualified than David? Maybe you should pose the same question to them, eh?

Grant McDermott said...

@Millhouse, David, and just about everyone else on this thread...

Well, seeing as no-one has picked up on my "economic" climate change points above, I might as well try with the actual science.

The IPCC is a sadly underutilised resource, but for a succinct, user-friendly summary of climate change science itself... you can do no better than the Skeptical Science website.

Seriously, I encourage EVERYONE interested in this topic to visit SS. There will find page upon page of rebuttals to CC skeptic positions... Starting with something as broad as "The effects of climate change aren't that bad"... to "CO2 is plant food" (which I see is a recurring theme in the thread above).

Please have a look. It's a fantastic resource and I think everyone will be better informed to take a position on CC after spending some time there.

dlr said...

David, I agree with you entirely. The aspect of the 'global warming debate' that I find most unconvincing is the relentless drumbeat of predicted negative consequences.

And yet all anyone has to do to see major advantages to global warming is to look at a map. Russia, Alaska, and Canada all contain enormous expanses of land that are unusable today by anyone. For example Canada has more land area than the US, and 1/10th of the population, almost all of it concentrated close to the border. If temperatures rose, all of that ice and snow/boreal forest would become as productive, and as receptive to life (all kinds, animal and vegetable as well as human) as the lower 48.


And if the Arctic Ocean became ice free that would be even better. Just think how useful it would be to be able to use the Arctic Ocean for shipping. It would make ocean transport much more efficient (read faster and cheaper).

There would be some downside of course, since presumably areas that are already too d@mn hot, like Louisiana & Florida, would become even less pleasant, or disappear altogether, but look at the relative size of Alaska & Canada vs Louisiana & Florida on the map. No comparison. And that's true on a global basis as well. The areas of Northern Europe and North America that would become more habitable are far larger, by orders of magnitude, than the areas that would become less habitable.

So I don't see how warmer temps per se are bad. The claim that I find worrying is that it will lead to drier weather. I personally find this extremely unconvincing. If temperatures rise, there is going to be more evaporation from oceans and lakes, which will lead to more rainfall not less. Which is also nothing but good news, leading to more vegetation and animal life.

dlr said...

I have also read that most of the warming is expected to take place at higher latitudes and more during the winter than the summer.

So Minnesota warms up quite a bit, but Bangladesh very little.

This is due to the fact that H2O (water) is a very potent greenhouse gas, much more so than CO2, and that places that have a great deal of humidity in the atmosphere already trap a great deal of the heat by the H20 in the atmosphere. Conversely, places that are very dry will see a much more pronounced reaction.

The places that most of us think of as being dry are places like the Sahara, etc, but the REALLY dry places are the high latitudes. And they are MUCH dryer in winter than in summer. So most of the effect will be on cold winter nights in Canada, Alaska, and Siberia.

Anonymous said...

It's a fact that most people live on coastal areas. Most major cities, for example Shanghai, Tokyo, New York and Los Angeles are situated on coasts. Also, most agricultural land is situated on or near coasts. Thus, the rise of sea level is a problem for human settlements and for food production. However, the sea level is expected to rise less than a meter. This does not pose a major threat, because the rise is miniscule, most cities situated at least for the most part on a higher ground than this. Manhattan would be the biggest sufferer in the USA especially because of the real estate mass, but the problem could be solved by few short dams and spillways. Furthermore, the argument about a mass extinction of species is kind of moot, because the species will travel to more suitable areas when climates and habitats change. And climates do not change much in the tropics, because the change happens near the poles as ocean currents and winds push warmth towards the poles. My opinion is that global warming is real, but it is used by the leaders of the world in an exaggerated form to wane us off of fossil fuels, especially oil that is peaking and going into permanent decline. Otherwise the world economy would go cold turkey in the coming decades. The global warming strategy gives humankind a reason to lower the consumption of oil before its price hits high. It's a political measure, further supported by the fact that while methane is a 30 times stronger greenhouse gas, we concentrate on carbon dioxide that results from the burning of fossil fuels.

Anonymous said...

In Australia an erstwhile Prime Minister stated the science of climate change 'was settled' and here is me thinking science in never settled soIi didn't vote for her and her 'Carbon tax' - just repealed in sept 14- I guess if Gore was an Australian citizen he would have !!