With polar ice melting raising the world's sea level by more than one-tenth of an inch per year, according to the Intergovernmental Panel on Climate Change, and Bangkok going in the other direction at an even faster rate, the prospects do not look rosy.

In fact, Thailand's top disaster expert predicts that, unless something drastic is done - and very soon - Bangkok will disappear under the waters by 2030 at the latest. Every 10 years, another 75cm of water will be added until, by 2100, Bangkok will be a modern-day Atlantis (the legendary city supposed to lie on the bed of the Atlantic Ocean).

One might be tempted to dismiss the predictions of Smith Dharmasaroja, head of Thailand's National Disaster Warning Center, as unduly alarmist if it wasn't for the fact that, some years in advance, he accurately predicted the 2004 Indian Ocean tsunami that caused so much death and destruction.

It is not just the up-country floodwaters that threaten Bangkok, however. High tides add to the misery, which has worsened with the concreting of coastal mangrove swamps that used to offer some protection. Dharmasaroja is urging an immediate start to the construction of a huge dyke across the Gulf of Thailand at an estimated cost US$2.8bn to halt this threat.

While nobody disputes that Bangkok is sinking, other experts are more sanguine, insisting the sea will flow in and recede with Thailand's rainy and dry seasons, leaving the area uninhabitable for only about 60 days a year. Well, that's a relief! If I live in Bangkok I just have to make sure I'm away for that period, returning just in time for the annual cleanup and lodging my insurance claim!

And what about drinking water? Every supermarket there has been stripped of bottled water as the tap supply becomes contaminated. Can a large city survive purely on bottled water for any length of time? Surely not.

Bangkok's experience is not an isolated one. Many coastal cities face the same threat (e.g. Venice). In China, Tianjin and Shanghai on the coast and Beijing and Taiyuan inland have all seen significant subsidence. The translation of 'Shanghai' as 'above the sea', in particular seems rather ironic.

In 2000, the People's Daily reported: 'A side effect of its breakneck pace of development, Shanghai is slowly sinking into the sea.' Just as Bangkok, this involves a combination of rising sea levels, excessive use of groundwater and intensive construction of super highways and high-rise buildings on an insecure coastal alluvial plain.

Shanghai now promotes the replacement of extracted water and is constructing extensive levees to keep back the surging sea. Again, however, as in Bangkok, land reclamation to meet the city's rising demand for industrial and residential space is eroding natural defenses.

The author is a columnist with China.org.cn. For more information please visit:

http://www.ccgp-fushun.com/opinion/geoffreymurray.htm

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