Keynesian Krugmanite Climatology Confusion

Paul Krugman writes about climates, "In the long run, we are all extinct."

This, of course, is a play the response by Keynes to economists who had raised problems about the long-term problems with Keynesian economics. "In the long run, we are all dead," said Keynes.

Krugman writes in full on climate:

Via Michael Roberts, a new paper (pdf) by James Hansen and associates that helps clear up a couple of points about climate change.

The first is the relationship between extreme weather events and climate change. The normal, cautious thing is to say that there’s no way to attribute any particular event, like a heat wave in the Ukraine, to global warming — and news media have basically been bullied by this argument into rarely mentioning climate change even when reporting on extreme weather. But Hansen et al make an important point: this argument is much weaker when we’re talking about really extreme events, like temperatures more than 3 standard deviations above historical norms. Such events would almost never happen if there weren’t a rising trend in global temperatures; so when they become quite common, as they have, it’s fair to call them evidence of warming.

The second point is how we know that climate change is a bad thing — a question I sometimes get asked. The questioners wonder why the fact that, say, more of Canada becomes agriculturally viable doesn’t offset the damage in places that get too hot.

My first-pass answer is that we have a global economy that is adapted to historically normal climate — not just in terms of what is grown where, but in terms of where we locate our cities. In the long run, after a couple of centuries’ worth of urban development and infrastructure has been drowned by rising sea levels and/or made useless because previously habitable regions need to be abandoned, we might be able to reconstruct an equally productive economy; but in the long run …

But Hansen et al make a stronger point: life as we know it evolved to fit the historical range of planetary temperatures. In the long run it might be able to adapt to a changed world — but now we’re talking millions of years.

In the long run, we are all extinct.

Even if we grant Krugman's premise that the globe is warming, there are serious problems with Krugman's model.

First, he seems to assume a fairly rapid change in climate, while an extremely slow adaptation by mankind to changes in climate, thus his quip, "In the long run, we are all extinct."

First, on a personal level, it would seem that because of rising waters, that people in an area that becomes uninhabitable because of water, would move to drier ground immediately. They aren't going to wait a week, a year, or a million years before moving.

Secondly, if Krugman is implying that some farm areas would be damaged, wouldn't those in new farm areas, such as Canada start to grow crop immediately.

On a macro level, Krugman seems to have forgotten basic economics once again. Supply and demand factors would push up prices, if there was less supply, this would push other actors into the farming sector, because of the rising prices.

There would  also be a  push for other actors into the development of infrastructure for these newly developing regions.

One would think that Krugman, as a Keynesian economist who is in favor of a battling space aliens to stimulate the economy, would thus be in favor of global warming to stimulate the growth of infrastructure work in new regions. That he seems not to be, is another great inconsistency in Krugman thinking.

Bottom line: In the long run and the short run, you can count on Krugman to be generally confused and inconsistent.