Based on my comments I take it that I am still not making myself clear on Climate Change in America.
A few more direct points
(1) Its not that rebuilding America would be a good thing because it produces jobs. Or that spending money or seawalls or air conditioning contributes to GDP. Its that these are bad, but they are not that bad. They are a cost but not a great cost.
(2) Cranking up really big damages almost always comes from loss of life. What reason do we have to suspect that lots of lives will be lost in the United States from Climate Change?
(3) There is a big difference between whether Climate Change will be bad for the United States and whether it will be bad for the rest of the world. Again big damages come from loss of life.
Yet, if those lives are in other nations they don’t show up as damages for the US. This is a central issue. Many folks may want to inflate the damages for the US so as to motivate Americans to do things that primarily benefit people in other countries. I understand the motivation here but simply see it as my role to say what, as best I can tell, is true.
Additionally, calculating damages outside the US is extremely tricky because its going to depend crucially on how developed the rest of the world is by the time the effects kick in and what international immigration policies are.
If in 100 years we wind up with a mostly developed globe and relatively free immigration the damages to climate change will probably be small for everyone.
If Africa and South Asia stay poor then there is a much different story.
(4) It is of course possible that climate change could be much worse than we imagine but this is true for all sorts of risks. The next flu could be worse than we imagine. The violence from revolutions in the Middle East could be worse than we imagine. Nuclear proliferation could be worse than we imagine. The probability of an asteroid strike could be worse than we imagine. The probability of mega-earthquakes could be worse than we imagine.
All of these things could go really badly and cause lots of death and destruction. We have to try to weigh these things as best we can and balance our efforts. This is the point of trying to get a handle on expected damages.
Moreover, recognizing our general uncertainty about the future makes it less sensible to invest heavily in one particular cause.
All that having been said you can still make the case for a carbon tax. Its just that the case centers around damages that are in the 5% of GDP range for the US.
8 comments
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Friday ~ March 18th, 2011 at 2:41 pm
My name here
My main concern around climate change is that the earth becomes like venus. As more CO2 is released into the atmosphere the earth become warmer, this is due to a well know effect of the interaction between certain wavelengths of light and CO2. The earth becoming warmer increases the rate at which CO2 goes into the atmosphere, this means we have a situation with feedback and the possibility for exponential growth in temperatures. The predicted amount of warming in the next century may be manageable, but what about the century after that, if it is an exponential increase it also becomes harder to do anything about this the longer time goes on. These are my main concerns, but, if you are not concerned about the fate of the human race for time periods of more than ~100 years from now this is not a particularly compelling argument. I currently believe that most people fall into the category for which this argument is not compelling.
Sunday ~ March 20th, 2011 at 5:51 pm
Nick Bradley
I don’t even think such a scenario is physically possible through AGW.
http://wattsupwiththat.com/2010/05/06/hyperventilating-on-venus/
Friday ~ March 18th, 2011 at 3:16 pm
Roland
With the exception of the asteroid (a very low probability event, probably avoidable with current technology) the other extreme dangers you identify, while subject to a great deal of uncertainty, do not expose us in the same way. We are living through a worst case nuclear scenario now. Losing a city to a nuclear strike by a terrorist (although a fervid fear on the right) is also a low probability event. A flu pandemic would be bad but manageable. On the other hand, an out-of-control spiral in our atmosphere is a very different kind of problem, against which I am willing to buy insurance.
Friday ~ March 18th, 2011 at 3:49 pm
Barry
“(2) Cranking up really big damages almost always comes from loss of life. What reason do we have to suspect that lots of lives will be lost in the United States from Climate Change? ”
Evidence? For just one example, warming will affect the snowpack in the Rockies, Sierra Nevadas and other places which feed California’s water systems. Right now, the snowpack acts as a free, very large dam system; many more dams will have to be built as substitutes.
Military costs – what cost the oil-intensive economy in terms of wars? What costs (just to us) would be added when a billion-odd people get stepped on and pushed around by climate change?
Friday ~ March 18th, 2011 at 3:52 pm
IVV
Venus? Really?
The planet doesn’t even have decent rotation–a day on Venus is about 120 Earth days, robbing it of a large magnetic field. Its atmosphere is 96.5% carbon dioxide, as opposed to Earth’s 0.04%. You’d have to displace Earth’s nitrogen. You’re right, it’s not compelling at all.
But in any case, we need to learn more.
Saturday ~ March 19th, 2011 at 10:15 am
stickman
Karl,
Your position here is similar to the bargaining issues highlighted by Thomas Schelling (see here for instance)… So at least you can count yourself in good company!
You are right that (current) projected damages to the US are not particularly significant. However, as you have already intimated, you are still left with the thorny issue of ethics; both interregional and intergenerational. Further, I believe you are overlooking some trends that will directly and significantly affect the US. (FWIW, Schelling is one of my intellectual heroes, but I think he is making some of the same mistakes – at least in the article that I’ve linked to above.) Thus…
In response to your previous post, I’ve just added a comment (sorry: I’m late to the party) outlining three major economic reasons for acting aggressively against climate change. One of these was the relative prices argument, which might be best illustrated via the concept of rising food prices. Even though agriculture is less than 3% of US GDP, if climate change caused national food production to fall by half it would result in a far great loss of GDP than 6%.[*] Food prices would rocket upwards, crowding out all other forms of investment. You could, of course, extend the analogy to a global level and see that decreases in agriculture productivity could directly impact American citizens even if those agricultural losses are incurred far away. Say, I don’t know, from a massive heatwave and drought in Russia…
The mistake in many (economic) climate models is to assume perfect substitutability between environmental and man-made goods, which then means you impose a false linear relationship between damages to the environment and the gains from material goods.
o-[-<
[*] Yes, I realise that agricultural production in the US might actually increase with moderate warming. My point here is merely to use food prices for purposes of illustration because it is a concept that everyone can identify with… Particularly at the current moment.
Saturday ~ March 19th, 2011 at 7:19 pm
Mike
I think one way to phrase this disagreement is a “Seeing Like an Economist” problem – science can only understand what it can quantify, and you aren’t worried on all the things that economists have found data and theory for measuring historically. Environmentalists believe that there is a lot more out there in terms of the damage to the ecosystem that won’t show up in the data until it is too late.
My worry is that the cost-benefit analysis here is too elementary. If we do a CBA on building a bridge, it’s easy to incorporate a second stage where, if it was wrong, the cost of destroying the bridge. I don’t see much reflection on the cost of fixing AGW 70 years from now if the estimate is wrong. Indeed, I think it would be mostly impossible, no?
That would make planet Earth a “sunk cost”, in the jargon.
Saturday ~ March 19th, 2011 at 7:43 pm
stickman
Even though agriculture is less than 3% of US GDP, if climate change caused national food production to fall by half it would result in a far great loss of GDP than 6%.
Good Lord, I’ve just read over my comment and seen this embarrassing typo… It’s not possible to edit, is it?
Clearly, I should have said:
“Even though agriculture is less than 3% of US GDP, if climate change caused national food production to fall by half it would result in a far great loss of GDP than 1.5%.”
Note to dyslexic self: Proof-read before posting.