George Will raises an interesting question

From the Washington Post:

The housing perhaps-not-entirely-a-crisis resembles, in one particular, the curious consensus about the global warming "crisis," concerning which, the assumption is: Although Earth's temperature has risen and fallen through many millennia, the temperature was exactly right when, in the 1960s, Al Gore became interested in the subject. Are we to assume that last year, when housing prices were, say, 10 percent higher than they are now, they were exactly right? If so, why is that so? Because the market had set those prices, therefore they were where they belonged? But if the market was the proper arbiter of value then, why is it not the proper arbiter now?

I'm not too worried about the housing "crisis."  House prices are falling.  So what?  Isn't that good for some and bad for others?  Houses in my neighborhood are losing value.  Tough luck for me--that's the way markets work sometimes.  Markets determine the "right" price.   

But what is the "right" global temperature? The current answer seems to be something at or lower than the current temperature.  But why?  Are we convinced that the current situation is better or worse than any other?  Are we sure that higher temperatures will result in worse conditions than current temperatures? 

Comments

[a.c.]

I don't think it's an issue of the "right" temperature, as much as how change is occurring, and in particular how *fast* it occurs.

[Joe Otten]

There has, IIRC, been research suggesting that increases below 2 degrees will benefit temperate regions with faster crop growth and lower heating costs. Above 2 degrees the costs outweigh the benefits, and in tropical regions any increase is costly.

Obviously, as usual, everybody on both sides objected to this research.

[Don]

Actually, we will get to see a range of new temperatures, because the current processes have no regulation, more and more CO2 and more and more warming.
Arctic people and those living on low coastlines are feeling the changes now, as is Las Vegas as water levels of their water source fall. Of course, Will will not see much change before the end of his days, or will the moss backs in the fossil fuel industry. One could read Mark Lynas' "Six Degrees of Warming" for a reasonable scenario.

[Don]

As luck would have it, Will's wisdom was manifested upon us simultaneously with an accounting of the measurable effects upon the biosphere owing to global warming to present, published in Nature this week! You can read about it on "Climate Feedback," one of Nature's blogs.
http://blogs.nature.com/climatefeedback/

[Tim Haab]

Don,

Youve missed the point of the question. I understand we can document the effects. But what is the goal? At what should policy be targeted? No changes? That doesn't seem reasonable. But then, what are acceptable changes? Only those that nature intends?

[Dan Riley]

a.c. is correct that how fast matters as well as how much. wrt Joe's comment, the IPCC says roughly the same in the ar4 wg2 Summary for Policymakers, pg. 17 (time scale is the 21st century): "For increases in global mean temperature of less than 1-3 C above 1990 levels, some impacts are projected to produce benefits in some places and some sectors, and produce costs in other places and other sectors. [...] It is very likely that all regions will experience either declines in net benefits or increases in net costs for increases in temperature greater than about 2-3 C."

[odograph]

Tim asks:

"Are we sure that higher temperatures will result in worse conditions than current temperatures?"

Well, as an economist you have two choices. You can research the pertinent science, or you can ask that same question again next year.

[Bob Murphy]

Good post! Yeah, it's funny when you phrase it that way, and say, "So is the global mean temperature the exact optimum right now?"

However I think that might be a bit unfair. For one thing, I think a lot of those who are very concerned about climate change could quite consistently say, "No it's not, look at all the damage that has already been done. Ideally we would not only stop adding CO2, but we'd remove some of what we've already pumped into the atmosphere."

For another thing, if someone views humans as meddling with Nature (yes capital "N"), then I think he or she could consistently say that any change is unjustified, regardless of the overall net effect.

E.g. suppose some kids are playing baseball and they knock out the transformer outside an apartment building, so that everybody inside loses power. The residents are really mad and want to sue the kids for their spoiled meat, milk, etc.

But the kids' lawyer learns that a hacker in the building was just about to upload a very nasty computer virus when the power went out; the FBI tracked him down and arrested him before the power was restored. So in terms of overall economic consequences, it was actually good that those kids messed with the power.

I don't know the law in cases like this, but I would be surprised if the other tenants couldn't sue the kids anyway for the damages that they suffered.

So anyway, my overall point is that I think a lot of environmentalists view humans as messing with nature, and that it's beside the point to talk about the overall net impact of this meddling. (I don't agree with this view, mind you.)

[Don]

Tim: I'm struggling with the point of your question. Homo sap has pretty much occupied the whole world now and is using a huge fraction of natural resources (water for growing food, atmosphere for dumping our waste, land for the gamut of our activities, etc). It is a very reasonable assumption that we (humanity as a whole) will be able to extract less of what we need (food, fish, fiber) as temperatures rise to: melt the ice, redirect storm track and rain fall, increase extremes (violent storms, droughts, heat waves). Now, I do not doubt that people like G. F. Will and the board at Exxon-Mobile will continue to live well, but the rest? One other point that I might raise is who, what is this "nature" that you talk of? Is "nature" business as usual or ?

[Alan Dove]

Sorry to catch this post so late, but hopefully someone is still following it. The answer here actually seems quite simple: our current human world was built on the assumption of a relatively fixed climate, with the average temperature staying within a few degrees of where it was back when George Will was first getting interested in politics. Now, we have all of this infrastructure resting on that environmental assumption - coastal cities, farming regions, water supplies, transportation routes and so on. Unfortunately, anthropogenic temperature increases are going to wreak havoc with all of that.

[David]

Alan's spot on and the question is based on a false premise. No-one needs to have any view on what the 'optimum' temperature is to realise that a temperature a few degrees higher than now has net costs. The 'economically optimum' temperature we should be aiming for is not what it is now, or what it was in the 60s, or some guess at what the 'natural' temperature is - it's simply the temperature above which the likely costs of adaptation start to (drastically?) outstrip the costs of keeping the temp at the level. The assessments we've got so far indicate that once we get a couple of degrees above now, the likely costs (risk x $) escalate substantially.