Sunday, July 05, 2009

Does Climate Catastrophe Pass the Giggle Test?

The argument for doing drastic things to prevent global warming has two parts. The first has to do with climate change, with reasons to think that the earth is getting warmer and that the reason is human action, in particular the production of CO2. The second has to do with consequences of climate change for humans.

Most of the criticism I have seen, in comments to this blog and elsewhere, has to do with the first half, with critics arguing that the evidence for global warming, or at least the evidence it is caused by humans and will continue if humans do not mend their ways, is weak. I don not know enough to be sure that those criticisms are wrong; pretty clearly climate is a very complicated and not terribly well understood subject. But my best guess, from watching the debate, is that the first half of the argument is correct, that global climate is warming and that human action is at least an important part of the cause.

What I find unconvincing is the second half of the argument. More precisely, I find unconvincing the claim that climate change on the scale suggested by the results of the IPCC models would have catastrophic consequences for humans. Obviously one can imagine climate change large enough and fast enough to be a very serious problem—a rapid end of the current interglacial, for example. And if, as I believe is the case, climate is not very well understood, one cannot absolutely rule out such changes.

But most of the argument is put in terms not of what might conceivably happen but of what we have good reason to expect to happen, and I think the outer bound of that is provided by the IPCC models. They suggest a temperature increase of about two degrees centigrade over the next hundred years, resulting in a sea level rise of about a foot and a half. What I find implausible is the claim that changes on that scale at that speed would be catastrophic—sufficiently so to justify very expensive measures now to prevent them.

Human beings, after all, currently live, work, grow food in a much wider range of climates than that. Glancing over a U.S. climate map, it looks as though all of the places I have lived are within an hour or two drive of other places with an average temperature at least two degrees centigrade higher. If people can currently live, work, grow crops over a temperature range of much more than two degrees, it is hard to imagine any reason why most of them couldn't continue to do so, about as easily, if average temperature shifted up by that amount—especially if they had a century to adjust to the change. That observation raises the question with which I titled this post: Does climate change catastrophe pass the giggle test? Is the claim that climate change of that scale would have catastrophic consequences one that any reasonable person could take seriously?

I can only see two ways of defending such a claim. The first is some argument to show that present arrangements are, due to divine intervention or some alternative mechanism, optimal, so that any deviation, even a small one, can be expected to make things worse. The second, and less wildly implausible, is the observation that people have adapted their activities—the sort of houses they live in, the varieties of crops they grow—to current conditions. Put in economic terms, we have sunk costs in our present way of doing things. Even if the planet has not been optimized for us, we have optimized our activities for the planet, with the details depending in part on the local climate. Hence any change in either direction can be expected to be a worsening, making our present way of doing things less well adapted to the new conditions.

That would be a persuasive argument if we were talking about a substantial change occurring over five or ten years. But we aren't. We are talking about a not very large change occurring over a century. In the course of a century, most existing houses will be replaced. If temperatures are rising, they will be replaced with houses designed for a (slightly) warmer climate. If sea levels are rising, they will be replaced, in low lying coastal areas, with houses a little farther inland. Over a century, farmers will change at least the varieties they are growing, very possibly the kind of crop, multiple times, in response to the development of new crop varieties, shifting demand, and similar changes. If temperatures are rising, they will gradually shift to crops adapted to a (slightly) warmer climate.

Climate aside, we do not live in a static world—consider the changes that have occurred over the past century. The shifts we can expect to occur due to technological progress alone, even without allowing for political and demograpic shifts, are much larger than the shifts required to deal with climate change on the scale I am discussing.

My conclusion is that this version of climate catastrophe, at least, does not pass the giggle test. There may be other versions, based on more pessimistic predictions of climate change, that do. But the claim that we now have good reason to expect climate change on a scale that will produce not merely problems for some but catastrophe for many is one that no reasonable person should take seriously.


Anonymous said...

"In the course of a century, most existing houses will be replaced."

While I'm sure that that's true overall, I'm struck by how weird a statement it must seem from the perspective of Europeans. I was just having a discussion a few days ago with some people from Britain about air conditioning, and even new dwellings there seem to be almost universally designed as though they were hundreds of years old; there's little or no provision for adding central air, and they argued that no one would want the kind of heat exchangers that sit beside nearly every house in the US South. This view that their grandchildren will live in the same kinds of homes that they now live in may contribute to some of the hysteria.

Tim Lambert said...

2 degrees of warming would not be catastrophic. Which is why the policy goal is to limit warming to that much.

And you don't need drastic action to reduce carbon emissions over decades. Junking all existing coal-fired power plants would be tremendously expensive, but over several decades they would all have to be replaced anyway, so all you do is replace them with nuclear (or wind or solar or whatever).

Your post doesn't pass the giggle test.

Anonymous said...

Concur with Lambert. Gradual replacement of all coal-fired plants with nuclear over the next few decades is the way to go. It's the safest thing to do.

Anonymous said...

Thirded. I really don't understand your fixation on climate change. Your posts about climate change come across as ideological, not scientific.

Ben Rast said...

Humans have already survived several climate changes, and will no doubt demonstrate the adaptability to survive several more...unless they waste all their precious time and resources in trying to prevent the inevitable.

If we cannot manage the weather, what on earth makes us think that we can manage the climate?

Patri Friedman said...

The idea that replacing coal-fired plants with nuclear is free does not pass the giggle test. I don't think China is using coal because they like the soot, I think they are using it because the plants are cheaper and easier to build. Let's go check Wikipedia:

"There is a possible impediment to production of nuclear power plants as only four companies worldwide (Japan Steel Works, China First Industries, OMX Izhora and Doosan Heavy Industries) have the capacity to forge single piece containment vessels [32], which reduces the risk of a radiation leak. Japan Steel Works can only make four reactor vessels per year, though it will double its capacity in the next two years.
A 2007 status report from the anti-nuclear European Greens claimed that, "even if Finland and France build a European Pressurized water Reactor (EPR), China started an additional 20 plants and Japan, Korea or Eastern Europe added one or the other plant, the overall global trend for nuclear power capacity will most likely be downwards over the next two or three decades. With extremely long lead times of 10 years and more [for plant construction], it is practically impossible to increase or even maintain the number of operating nuclear power plants over the next 20 years, unless operating lifetimes would be substantially increased beyond 40 years on average."[38] In fact, China plans to build more than 100 plants"

Hmm, it's almost as if the status quo is being done b/c it is the best solution, and this magic technology can't actually be implemented right away...imagine that.

I think nuclear power is awesome, but the idea that it is costless or even possible to convert large numbers of coal-fired plans without making power more expensive is ludicrous.

Anonymous said...

Strawman alert, no one said replacing coal with nuclear was free?

montestruc said...

I think the big deal is the change of sea levels that will follow significant shifts in global temperatures.

Small shifts in sea level (less than say 0.3 meters or ~ 1 foot) will have impact, but not enormous ones, but when you start talking double or triple or more than number (which is possible, and has happened in geologic history) then you start having serious problems.

Why, first off the vast fraction if not the majority of the human population population live very close to sea coasts and on relatively flat land. If you move the sea level up a meter, that will move the coastline a much, much longer distance.

Further their is the economic uncertainty of where the shoreline is going to "end up" at.

I looked at this in detail and found that hypothetically if all land supported glacial ice melted the sea level would rise on the order of 250 feet, and if we have a return of ice ages it can drop more than that.

Imagine the economic consequences to someone who owns coastal real estate, and the kind of market panic that can cause if sea levels were actually rising (or falling) fast enough, and consistently enough for people to care, like an inch a year or so.

G-Man said...

The other issue is that we Americans, and most Europeans, Japanese, Australians and so on can afford to adapt to climate change.

It's places like Africa, and Bangladesh, &c. that can least afford to adapt, and will likely suffer the bulk of the consequences.

Anonymous said...

It's being argued that we ought to make a very large investment now for a return decades if not a century in the future. The idea we can even begin to understand to rate of return and opportunity costs over that period is nuts.

The present value of a trillion dollar system of dykes a century from now is peanuts. What outcome justifies hundreds of billions investment now?

I fully agree with people who argue we ought to be spending now to prevent or mitigate absolutely catastrophic outcomes, but like you I have don't know what those outcomes are supposed to be. Venusification, sure, but what else is worth the significantly decreasing energy usage?

Jon said...

Coal fired generators are not necessarily "dirty". The emmissions can be scrubbed and the flyash is a good building material. Scrapping the idea of using coal for energy is madness, expecially with the huge deposits available.

Anonymous said...

David, you look at the average forecast and declare "there's no catastrophe".

This focus on the average would make sense if we expected Nature to give us a sufficient warning of the catastrophe. Then we could "think of it when it comes". And for now, we could just plan for the average.

Alas, we might not get a timely warning. Think "fat tails" (in the climate sensitivity PDF) and "carbon feedbacks". Temperature rise from CO2 takes decades to eventuate. For CO2 sinks/sources to be affected by the higher temperatures, also takes time.

Therefore we should look at the whole range of future scenarios, not merely the average.

May I also correct you on these:

1. The problem for agriculture is not warmth but mainly moisture: more evaporation, more evapotranspiration, and generally unfavourable re-distribution of precipitation. (Even though precipitation overall should increase.)

2. Two degrees C by 2100 is outdated. Newer estimates indicate 3-4C as average under BAU.

3. IPCC's estimate of sea level rise is not a full estimate. As IPCC clarify, it only includes the least controversial processes.
Alas, it's the processes least understood -- "dynamic ice flow" --that matter the most.

Comparison with distant past (Plio-Pleistocene)indicates, 2-3 C should eventually cause a 15-35 m rise. Granted, over millennia. But the rise may not be evenly paced.

Capn said...

I prefer to call it ClimateFaith.
The sun, and the sun spots have more to do with the climate of earth -- and Mars than anything the hairless apes can do. But follow the checkbooks.

But, as far as controlling emissions, didn't Milton Friedman recommend a pollution exchange program in 1970?

Mercy Vetsel said...

I would list four steps in the logic behind "cap and trade" legislation:

1) The planet is warming and the last 10 years have just been a hiatus in the secular warming trend.

2) Human produced CO2 has been the primary cause of this warming.

3) The sensitivity (i.e. ratio of direct greenhouse warming to actual warming) will shift from the value of less than 1 witnessed over the last century to a value of 2 to 4 over the next 100 years. This will involve a positive feedback effect and the computer models used to achieve this range of values accurately represents the components of the system.

4) It makes sense to enact extremely expensive symbolic measures loaded with corporate welfare, pork and federal micromanagement which scientists from all sides of the debate agree will have no measurable impact on temperatures in the hope that it is "step in the right direction" that will trigger the more drastic changes required.

Point 1 is fairly solid, point 2 is possible although currently undetermined, point 3 is completely unsubstantiated and opposed to the historical evidence and point 4 is patently absurd.

Even Greenpeace seems to be some agreement with me on point 4 in relation to the authoritarian, corporate welfare idiocy recently passed by the house.

The direct greenhouse warming effect is logarithmic and we've already achieved MOST of the direct warming expected from the doubling of CO2 expected by 2100.

This means that if we're about to set off a positive feedback snowball then we would need to make huge, drastic cuts now. In fact it's probably too late. We're already on the horizontal portion of the log curve.

Overall, I think it's completely unjustified to use unproven (actually disproved) computers models for baseline sensitivity use to project future temperatures rather than the empirically measured sensitivity of the past 100 years.


Alex Perrone said...

The argument I often hear for the undesirable effects of climate change is not the temperature change in itself, but its effects on extreme weather. People can easily stand a 2 degree average temperature change, but an average is just one metric. We have to look at the distribution of temperature (such as extreme highs and lows) and distribution of other occurrences (hurricanes, typhoons, etc).

In fact, one could imagine a scenario with extreme highs and lows that would not change the average temperature anywhere but would be catastrophic.

Just a little media support for the argument against global warming because of extreme effects:

The duration and strength of hurricanes have increased by about 50 percent over the last three decades, according to study author Kerry Emanuel, a professor of atmospheric science at the Massachusetts Institute of Technology in Cambridge.

Emanuel's finding defies existing models for measuring storm strength. Current models suggest that the intensity of hurricanes and typhoons should increase by 5 percent for every 1ºC (1.8ºF) rise in sea surface temperature.

Tim Lambert said...

The IPCC models give a range from 1.1-6.4 degrees of warming this century. These are the average for the planet and the land will warm more than the ocean. It is completely wrong for David to say that the most likely value is 2 degrees of warming.

Anonymous said...

Tim, your numbers are BAU, aren't they?
Could you also cite mode, mean and median for that distribution ranging from 1.1 to 6.4?

Hammerhead said...

Suppose we are actually beginning a Maunder minimum again (another 'little ice age') Will the governments do an about face wrt to CO2 emissions? How will a cooling planet adversely impact the poor of the world? Signing Kyoto has done nothing to further the technology of achieving 'climate control'. The sun and its spots may very well have a much larger impact on the earth's climate than our current industrial output. The debate is most certainly not over on this.

Is the goal to, over the centuries, achieve at whatever cost it takes a government-decreed unchanging average global temperature? Kind of a CAFE requirement for the weather? BTW, the last couple of hurricane seasons have been pretty average. Weather has always been violent, human narrative histories are loaded with floods, fires, droughts, famines, freezes, storms.

Granite26 said...

I'm convinced we should be doing something, but I'm not convinced that anything (I.E. CapNTrade as currently proposed) is better than nothing. There are some good (flat tax) solutions that minimize the harmful effects. This isn't one of them.

I'd also like to bump the rising sea levels issue. A foot or so in higher sea level represents a LOT of land.

Finally, has anyone done research on what adding a foot of water everywhere (and taken from the poles) would do to the geology? Thats a lot of weight!

David Friedman said...

Checking the current, 3rd, IPCC webbed report, Tim is correct that the latest version has a wider range of temperatures than I said. Two degrees was the "best estimate" figure from the 2nd assessment.

In the current report, getting a figure close to 6 degrees required looking at 35 different scenarios, up from (I think) four in the previous report. Take it down to seven scenarios and the top figure is just above 4 degrees. My suspicion, looking at the graph, is that my two degree figure is still about right for the scenarios they used in the previous report--that the higher figures are the result of introducing additional, more pessimistic, scenarios. But I can't find in the webbed material which scenarios are the new ones, so I might be wrong.

But the question I was raising was not what the consequences would be of the worst possible level of global warming but of a level we could reasonably expect. Looking at the current projections, 2-4 degrees looks about right. That's higher than I thought, but still seems to me to lead to the same conclusion.

The graph I'm looking at from the 3rd report is:

David Friedman said...

Tim argues that a continuous change of replacing coal fired plants with nuclear, solar, or whatever would suffice. My guess is that that might well happen with no climate policy at all, merely a reduction in current constraints on nuclear plants--the cost of solar seems to still be falling.

But that isn't what we are seeing in proposed legislation justified by warnings of climate catastrophe.

David Friedman said...

Tim points out that the IPCC predicts land warming faster than ocean. He doesn't mention that it also predicts most warming in "northern high latitudes in the cold season." On the other hand:

"Only in south Asia and southern South America in June/July/ August, and Southeast Asia for both seasons, do the models consistently show warming less than the global average."

One might describe that as most global warming in the areas where warming is, from a human standpoint, most desirable--cold places in cold months--and least warming where it is least desirable.

But I don't think I have seen any news stories mentioning that feature of the projections.

David Friedman said...


I forgot that in the southern hemisphere, June, July and August are winter months. Cancel the second part of the point of my previous post.

Anonymous said...

Let’s just suppose “The Science” is correct. The question is whether we should do anything to ‘fix’ the climate. One study showed that to adjust your personal temperature at the end of this century by the amount expected if we took the recommended IPCC actions in reducing CO2, could be achieved by relocating your house 30 miles closer to your nearest pole, or relocating in the same latitude to a 200 ft higher elevation.

Question 1- Do you think, to avoid the need to make such a relocation of your dwelling to maintain your comfort in 90 years time is worth paying trillions of dollars of your money now?

If your answer to Question 1 is Yes, then Question 2: Do you believe that giving trillions of dollars of more of your money to bureaucrats and money handlers will ever achieve anything good?

If your answer to Question 2 is Yes, then Question 3: Give an historical example where expenditure of such scale by governments on a single issue has worked before?

Tim Lambert said...

The 2nd assessment was in 1995. The most recent one is the 4th assessment. The reason for the increase in projected temperature rises in the 3rd assessment was "due primarily to the lower projected sulphur dioxide emissions in the SRES scenarios relative to the IS92 scenarios."

Just last month the NOAA released a report on the impacts of global warming on the US. See:

I think it better to look at that rather than guess that adaption will be cheap.

There is another IPCC report on mitigation -- they don't think it is that expensive as long as you do it over decades.

Hammerhead said...

Granite26 writes:
Finally, has anyone done research on what adding a foot of water everywhere (and taken from the poles) would do to the geology? Thats a lot of weight!

If you are referring to North Pole sea ice, floating ice, the answer is nothing will change (not even the sea level except by a negligible factor) because of Archimedes Principle.

Adding a foot (or fifty) of water to the oceans from melting land-based sheet ice would not add significant weight - the oceans are more than a mile deep. The weight of a mile-high glacier on the land is more significant, because of how it piles up. I believe North America is still 'rebounding' from last ice age where ice more than a mile deep extended across North America.

jdgalt said...

I agree with your point, but it's not even that simple.

To make a good case that we have a moral obligation to give up driving, eating meat, and other important parts of our accustomed lifestyle because of "global warming"/"climate change", it seems to me that the greens have the burden of proving an entire chain of propositions, including:

1. The earth is getting warmer as a long term trend.

2. This temperature increase can be expected to have results harmful to human life*, and those results can be expected to happen faster than we can adapt to them, even with technology. (* This is intended to be read broadly, so that harm to other life forms on which we rely would qualify.)

3. Human action is responsible for the change, or at least, the lifestyle changes they're asking of us would significantly alleviate it.

4. Alternative fixes such as Gregory Benford's boatload of iron filings would cost more or cause greater dangers.

All four of these propositions are wide open to doubt, to say the least. And with apologies to John Stuart Mill: Extraordinary demands on other people require extraordinary proof.

bobw said...

"Just a little media support for the argument against global warming because of extreme effects:

The duration and strength of hurricanes have increased by about 50 percent over the last three decades, according to study author Kerry Emanuel, a professor of atmospheric science at the Massachusetts Institute of Technology in Cambridge.

Emanuel's finding defies existing models for measuring storm strength. Current models suggest that the intensity of hurricanes and typhoons should increase by 5 percent for every 1ºC (1.8ºF) rise in sea surface temperature."

The hurricane expert, Kerry Emanuel of the Massachusetts Institute of Technology, unveiled a novel technique for predicting future hurricane activity this week. The new work suggests that, even in a dramatically warming world, hurricane frequency and intensity may not substantially rise during the next two centuries.
[April 12, 2008]

Anonymous said...

Check out famous physicist Freeman Dyson's new book that touches on the climate change topic. He proclaims himself a heretic on the accepted interpretation of the data and usual view of the projections.

Mercy Vetsel said...

> in the southern hemisphere, June,
> July and August are winter months.

Actually, June through August is still summer, but those months happen when we have winter.

For example today is July 13 the U.S., but January 13 in Capetown.


P.S. Apologies for the lame joke ;-) and to all of the South Africans, Ozzies and South Americans working in the States who have to endure an endless number of this!

ATWUSSD said...

Surviving the climate change should be no problem for people. There has been multiple changes throughout earth's history and people have managed. Just be sure to have some kind of climate disaster preparation plan. It will definitely help overall.

William B Swift said...

Read Dr Bruce Clayton's "Life After Doomsday". As he points out, making a serious attempt to prepare for a nuclear war (may its effectiveness for nuclear war stay uncertain!) will make hurricanes, blizzards, earthquakes, and wildfires mere blips in comparison.

William B Swift said...

And for the more general point - worrying about global warming is pretty silly with no more evidence either way than we currently have. And, even if it is real, we will probably benefit more than be harmed by it.

Misanthropy Today said...

I once wrote something about whether it was even ok to not believe in global warming and I was attacked by many people (guess which side of the political spectrum) who had probably known nothing about global warming 5 years ago but are now experts and evangelists. The mob mentality and indignant tone of their arguments should be enough to raise some eyebrows. As Montaigne remarked, "only the fools are certain".

Unknown said...

next time you think climate change is innocuous, watch this:

Milhouse said...

Disappearing forests? The USA has more forest now than it did 100 years ago.

neil craig said...

While it is true we don't know enough about climate to be scientifically certain that our actions aren't accidentally causing damage in the same way we must be at least equally unsure that our actions aren't accidentally preventing damage. Indeed since ice ages average avout 12,000 years apart & it is about 11,800 I think that is a greater risk than warming.

Another weakness to the alarmist argument is that we do know how to cool the planet, if that is required, for relatively trivial costs compared to Kyoto. Cheapest would be seeding the stratosphere with sulphur crystals, as history shows volcanos have repeatedly done. That alarmists are overwhelmingly opposed to that, as they are opposed to cutting CO2 by going nuclear, suggests they are no quite as worried about catastrophe as they claim.

Patri, while coal power is cheap it is not cheaper than nuclear, though it does require trained nuclear engineers, which may be part of China's bottleneck. French nuclear is costed at 2.6c per kwh & it is now fairly elderly. If politics allowed modern mass produced nuclear plants, with only a necessary amount of regulation I suspect it would be the cheapest. The current shortage of manufacturing capacity is not an inherent cost but a sign of how politics has prevented the industry's development.

Unknown said...

I had two arguments about anthropomorphic CO2. First I felt that atmospheric C14:C12 ratios would not show as older. However, I’ve been told that that ratio has changed due to the ancient carbon atoms found in fossil fuel. Strike the first argument. The second argument asks a serious question.

Is it even possible for CO2 to have a global warming effect? The absorption spectra of CO2 has three absorption peaks. (Only two have any significant heat absorbing effect.) The two significant peaks are so strong that somehow transporting half of the CO2 in our atmosphere to Mars would only raise the level of where 95% of the heat at those two wavelengths was absorbed by several hundred feet. In the same manner doubling atmospheric CO2 will simply lower that level.

I.e. there IS more CO2. So what?

There is an experiment that would change my mind. In a closed tube use mirrors to make a light path equivalent to the bottom 2500 feet of atmosphere. Sweep an IR beam through 99% of the energy corresponding to a black body at some reasonable average temperature. Start with hard vacuum to correct for mirrors and glass adsorption. Then fill with air with the proper amount of water vapor but no CO2. Then add CO2 in several dozen steps until the amount is double today’s CO2 levels.

Then do the arithmetic. Plot total atmospheric IR absorption for a 274K (slightly above freezing) blackbody vs. amount of CO2. Or pick whatever number is the average blackbody temperature of the Earth.

I suspect that the effect of CO2 concentration will be small. Pull out the water vapor and notice the greatly reduced absorption due to the lack of most important greenhouse gas known. (Perhaps the DHMO people are not kooks after all.)

muirgeo said...

I would suggest Mr Freidman read about climate tipping points. Likewise he should understand we are NOT talking about small changes and that the major extinctions of the past have been climate related. Mr Freidman should also read more on population dynamics and trends in water availability worldwide. Desertification is another good subject he might wish to pursue as well as the nature and causes of epidemics. There is at least some chance that Florida will be mostly underwater in less time then has passed since this country was founded.

If the potential impact of climate on his childrens future doesn't pass the giggle test it's because he' s acting like an ignorant silly little girl. Human civilization sits on a razors edge. Potential for water shortage, global epidemics, mass migrations, war and starvation could be closer than we think and its the unknowns that should worry us for change dramatic for all of the Earth history and extreme for the history of human civilization is certain to come. It's easy to assume we are invincible but in the end a mass die off or even extinction is something we as with any other species could certainly undergo.

So giggle Mr. Friedman and pass that post to your children and they to theirs .... I truly hope they find it funny. But if it ends up not being so funny maybe in it humanities redemption can be found 500 years hence and something of value can be saved from your foolish uninformed pigheadedness.

Joe said...

One of the biggest problems with increased temperature and CO2 levels is that plants love it: higher crop yields, greater plant diversity, more rapid reforestation. Oh, horror of horrors! Plants everywhere!

As for the sea level, we do know now that it's not getting hotter in the southern hemisphere like in the north and Antarctic ice sheets are growing. It could turn out that the arctic ice sheets shrink and antarctic ice sheets grow, and it all balances out in the end with no sea level change.

On the other hand, temperature could start getting colder again next year for whatever reason, since we're not really good at predicting climate at all.

Unknown said...

Back of the envelope economics:

New Orleans' levees cost around $4000 per foot, or $20 million per mile. The US has 2069 miles of Atlantic coast, 1631 miles of Gulf coast, 8683 miles of Pacific and Arctic coast (6640 miles are in empty Alaska), for 12383 miles total. Thus the cost of building a levee around the entire United States is around $246 billion, at present value and present technology.

US produces around 6.0 billion tons of CO2 per year. A proposed market price of $15 per ton of CO2 would be a "tax" of $90 billion per year. At a high discounting rate of 10%, and no change in CO2 production levels, over 100 years that's worth around $900 billion.
At a low discounting rate of 5% more typical for utilities, you're around $1.8 trillion.

You can scale these directly with what percentage of CO2 current level you want to target. In the 5% assumption, the levees are cheaper at 13.7% reduction in CO2, which is something like 1993 levels. Which are not low enough to stop the manmade part of climate change.

Therefore, let's just build some levees and tell everyone else to learn to swim.

Anonymous said...

It is disapointing that you accept the claim that humans via the production of CO2 are responsible for whatever global warming there may be. I ask you to evaluate the relative impact of three factors on global warming: the sun, changes in the earth's axis and CO2
Compared to the sun and earth's axis, if CO2 has any effect at all, it can only be very small. Finally, consider that CO2 represents only about 5% of all the greenhouse gases. The obsession with CO2 does not pass the intellect test.

Ed onWestSlope said...

At 6:08 AM, August 21, 2009, muirgeo actually acted the fool.

The idea of 'climatic tipping points' is interesting and useful for small areas (such as affected by vulcanism events) but very difficult to verify with large areas, such as a major part of the a hemisphere.

Climatic Tipping Points are useful for catastrophe arguments because nothing can be defined. This is not science, this is speculation. The predictive history of catastrophic climatic speculators is very poor.

Past history seems to indicate that climate over tens of years is fairly easily adapted to by people. It requires some moving & not being solely dependent on a particular foodstuff.

It is usually political change which causes so much trouble. Unfortunately, most of the catastrophic climatic arguments appear to be political.

Carl M. said...

Humans can rapidly adapt to climate changes -- it's called clothes shopping. Plants and animals are less flexible. One hundred years is a long time in human terms, especially in the modern era. It is an eyeblink in evolutionary terms.

Present value calculations make some sense for remediation technology. Today's solar cells are significantly better than two decades ago. Battery technology is oozing forward as well. So waiting for these technologies before going solar-electric or electric cars made sense, and it probably makes sense to wait even longer.

But we need to be careful using present-value calculations too much. Per capital GDP has been going up 2%/year in this country, but much of that is household tasks entering the monetary economy and growth of government. (I question whether government growth should be counted the same as real consumer spending; two teachers per 30 children isn't necessarily twice as much teaching.)

For wild plants and animals we need to apply a negative interest rate for present value calculations!!! Biodiversity is dropping. The wild "economy" has been shrinking drastically in the past few centuries.

neil craig said...

Muirgeo's catastrophism is somewhat weakened by the sole example he gives "SOME chance that Florida will be MOSTLY underwater in" 200 years. Even if that were a problem matching the benefits of more crops & most of Canada being turned into fertile praire does anybody really think that in 200 years, unless human progress is prevented, we will not have far better mechanisms of climate control (& everything else than today?

Of course we COULD also see the next ice age starting before then.

VangelV said...

The whole AGW argument fails to pass the giggle test.

First, the evidence is overwhelming that temperature change has been driven by natural forces. Second, there doesn't seem to have been much warming since the 1930s, which were clearly warmer in the US than the much hyped 1990s. (Given the fact that CRU has claimed that it has 'lost' the original surface data from which it makes up a general trend there is no evidence of substantial warming globally.)

But let us dispense with that part of the argument and look at what would happen if temperatures rose and the planet became warmer as it has been for much of its past.

History shows us that warming trends have been good for people, plants and animals because all three respond positively to warmer temperatures and negatively to cooling periods. Up until the green lobby became hysterical about carbon dioxide scientists considered optimum temperatures to be substantially higher than what we have today. Those warmer temperatures allowed for longer growing seasons, much greater biological diversity and greater argicultural yields.

Given the fact that most plants and animals evolved during periods when CO2 concentrations were much higher a doubling will have no negative effect. In fact, a doubling of CO2 would mean much greater pant growth and higher levels of biodiversity. (There is a reason why greenhouse operators add CO2 to their operations to improve yield.)

Sea level changes would not be a problem because a warmer planet would mean more moisture in the atmosphere and more precipitation that would cause Antarctic glaciers to grow thicker. It would also mean that arid areas that are currently unproductive would get rains once again as they had during past warming periods. Sea level increases certainly hasn't done much harm to most coastal cities around the world. Most of them have streets that used to be on the water that are now several blocks inland as governments and companies have used landfill to create valuable real estate.

The AGW argument is beginning to fail on a number of fronts. The science is clearly showing that there is no need to rely on CO2 changes to explain any of the changes in temperature trends and history is revealing that in the past warming trends brought prosperity while cooling brought us misery. If we ignore the politics and look to the science there is no problem.

Melanie said...

Carl, I agree with you!