For some years now, the debate over global warming has been dominated by fear. Understandably frustrated that their message might not be getting through, climate activists have been ratcheting up the rhetoric to the point where one could be excused for wondering whether they are quoting from scientific journals or the Book of Revelations. If nothing is done, we’ve been told, global warming would soon destroy “up to 40 per cent of the Amazonian forests,” cut African crop yields in half by 2020, turn the American Southwest into a new dust bowl within a few decades and melt the Himalayan glaciers, causing them to disappear completely “by the year 2035 and perhaps sooner.”
All very frightening, but none of it was based on solid science.
The chief Cassandra in this chorus of doom has been Al Gore, whose 2006 Oscar-winning documentary An Inconvenient Truth was unabashedly (and rather accurately) marketed as “the most terrifying film you will ever see.” Mr. Gore rightly was awarded the 2007 Nobel Peace Prize for putting climate change on the global agenda, but his penchant for hyperbole – as in “we have just 10 years to avert a major catastrophe” or we must take “large-scale, preventative measures to protect human civilization as we know it” – isn’t likely to win him any prizes for accuracy or good science.
Here’s a case in point. Mr. Gore and his acolytes speak darkly of the likelihood that, because of global warming, sea levels that may rise 15 or 20 feet over the next century. Let’s put aside for the moment the fact that, according to the best research we have (from the UN’s climate panel, which shared the Nobel Prize with Mr. Gore), global sea levels are not likely to rise more than about 20 inches by 2100 – a level that history shows we can deal with quite easily. Rather, let’s imagine that, over the next 80 or 90 years, a giant port city – say, Tokyo –found itself engulfed by a sea-level rise of the magnitude Mr. Gore suggests. It’s a truly awful prospect, isn’t it? Millions of inhabitants would be imperilled, along with trillions of dollars worth of infrastructure. Without a vast global effort, how could we possibly cope with such a terrifying catastrophe?
Well, we already have. In fact, we’re doing it right now. Since 1930, excessive groundwater withdrawal has caused Tokyo to subside by as much as 15 feet. Similar subsidence has occurred over the past century in a vast range of cities, including Tianjin, Shanghai, Osaka, Bangkok and Jakarta. And in each case, the city has managed to protect itself from such large relative sea-level rises without much difficulty.
The point isn’t that we can or should ignore global warming. The point is that we should be wary of fear-mongering. More often than not, what sounds like horrific changes in climate and geography actually turns out to be quite manageable. In research funded by the European Union, climate scientists Robert J. Nicholls, Richard S.J. Tol and Athanasios T. Vafeidis recently studied what would happen in the unlikely event that the entire West Antarctic Ice Sheet collapsed. The result, they found, would be a sea-level rise of 20 feet over the next hundred years – exactly Mr. Gore’s nightmare. But how calamitous would this really be?
