Climate and infrastructureProtecting vital infrastructure as sea levels rise
As the world gets warmer, sea levels are rising; it has been happening at a snail’s pace so far, but as it speeds up more and more low-lying coastal land will be lost; at risk are many of the world’s cities and huge areas of fertile farmland; the sea is set to rise a meter or more by the end of this century, swamping much vital infrastructure and displacing hundreds of millions of people; scientists are looking at various ways to slow down or reverse the rise in sea levels — and of ways of coping with its consequences
For some, the end may come slowly, as the seas creep a little higher each year. This was the fate of the ancient cities of Herakleion and Eastern Canopus, which took centuries to be swallowed up. Elsewhere, the land may be eroded by waves and swept away by currents, as happened to the medieval English port of Dunwich. Or disaster could strike almost overnight, when a storm joins forces with the tides to create a surge that overwhelms flood defenses, leaving the survivors wondering whether there is any point in rebuilding.
As the world gets warmer, sea levels are rising. It has been happening at a snail’s pace so far, but as it speeds up more and more low-lying coastal land will be lost. At risk are many of the world’s cities and huge areas of fertile farmland. The sea is set to rise a meter or more by the end of this century, swamping much vital infrastructure and displacing hundreds of millions of people (New Scientist, 1 July 2009, p 28). This is just the start. “Unless there is a rapid and dramatic about-face in emissions — which no one expects — the next century will be far worse than this century,” says glaciologist Bob Bindshadler of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
New Scientist reports that throwing trillions of dollars at the problem could probably save big cities such as New York, London, and Shanghai, but the task of defending all low-lying coastal areas and islands seems hopeless. Some say that it only seems hopeless and ask: What if, instead of fighting a rearguard action against the encroaching oceans, we stopped sea levels rising at all? Could we find a way to slow the accelerating glaciers, drain seas into deserts, or add more ice to the great ice caps of Greenland and Antarctica?
NS writes that these ideas might sound far-fetched, but mankind has gotten itself into such a bad situation that maybe it should start to consider them. If we carry on as we are, sea levels will rise for millennia, probably by well over ten meters. Slashing greenhouse gas emissions would slow the rise and ensure it peaks sooner and at a lower level, but the longer we prevaricate, the bigger the rise we will be committed to. Even if “conventional” geoengineering schemes for cooling the
