Who’s afraid of climate change?

IMAGINE that over the next 70 or 80 years, a giant port city – say, Tokyo – finds itself engulfed by sea levels rising as much as 4m or more.
Millions of inhabitants would be imperiled, along with trillions of dollars worth of infrastructure.
This awful prospect is exactly the sort of thing global-warming evangelists like Al Gore have in mind when they warn that we must take “large-scale, preventive measures to protect human civilisation as we know it”.
The rhetoric may sound extreme, but with so much hanging in the balance, surely it is justified.
Without a vast, highly coordinated global effort, how could we possibly cope with sea-level rises on that order of magnitude?
Well, we already have.
In fact, we are doing it right now.
Since 1930, excessive groundwater withdrawal has caused Tokyo to subside by as much as 4m, with some of the lowest parts of the downtown area dropping almost 30cm per year in some years.
Similar subsidence has occurred over the past century in a wide range of cities including Tianjin, Shanghai, Osaka, Bangkok and Jakarta.
In each case, the city has managed to protect itself from such large sea-level rises and thrive.
The point is not that we can or should ignore global warming. The point is that we should be wary of hyperbolic predictions.
More often than not, what sound like horrific changes in climate and geography actually turn out to be manageable and, in some cases, even benign.
Consider, for example, the findings of climate scientists Robert J. Nicholls, Richard S.J. Tol, and Athanasios T. Vafeidis.
In research funded by the European Union, they studied what the global economic impact would be if global warming were to result in a collapse of the entire West Antarctic ice sheet.
An event of this magnitude would likely cause the oceans to rise by, perhaps, 6m over the next hundred years – precisely the sort of thing that environmental activists have in mind when they warn about potential end-of-the-world calamities. But, would it really be all that calamitous?
Not according to Nicholls, Tol, and Vafeidis. Here are the facts.
A 6m rise in sea levels (which, not incidentally, is about 10 times more than the United Nations climate panel’s worst-case expectations) would inundate about 25,000sqkm of coastline, where more than 400 million people currently live.
That is a lot of people, to be sure, but hardly all of mankind.
In fact, it amounts to less than 6% of the world’s population – which is to say that 94% of the population would not be inundated.
And, most of those who do live in the flood areas would never even get their feet wet. That is because the vast majority of those 400 million people reside within cities, where they could be protected relatively easily, as in Tokyo.
In all, according to Nicholls, Tol and Vafeidis, the total cost of managing this “catastrophe” – if politicians do not dither and pursue smart, coordinated policies – would be about US$600 billion a year, or less than 1% of global GDP.
This may explain recent polling data showing that public concern about global warming has declined precipitously in the last three years.
In the United States, for example, the Pew institute reported that the number of Americans who regard global warming as a very serious problem had declined from 44% in April 2008 to only 35% last October.
More recently, a BBC study found that only 26% of Britons believe that manmade “climate change is happening”, down from 41% last November.
And, in Germany, Der Spiegel magazine reported survey results showing that only 42% feared global warming, compared with 62% in 2006.
Fear may be a great motivator in the short term, but it is a terrible basis for making smart decisions about a complicated problem that demands our full intelligence for a long period. – Project Syndicate
nBjørn Lomborg is the author of The Skeptical Environmentalist and Cool It, head of the Copenhagen Consensus Centre and adjunct professor at Copenhagen Business School.