Sea levels in the Gulf of Thailand are, in fact, falling slightly, Dr Suphat Vongvisessomjai said. Forecasts by the Inter-governmental Panel on Climate Change that global warming would cause sea levels to rise had been misapplied to the Gulf of Thailand, he said, urging the public not to panic.

The phenomenon will vary according to latitude, explained Suphat, a former professor at the Asian Institute of Technology's water resources engineering and management programme.

Global warming will cause significant rises in sea level in areas in the high and middle latitudes only, he said. These areas will be affected by melting glaciers and ice sheets, while areas close to the Equator will not, he explained.

"The climate change panel's projection was wrongly accepted to apply to the Gulf of Thailand. We are too far from melting glaciers or ice sheets [for sea levels to rise]," Suphat said.

He cited data from the Navy's hydrographic department that showed average sea levels at Koh Lak in Prachuap Khiri Khan and Sattahip in Chon Buri were 0.6 centimetres and 0.3 centimetres lower, respectively, over the past 8.6 years than the 25-year average between 1963 and 1987.

He also cited research from a Japanese team. In 1993 researchers Tetsuo Yanagi and Tatsuya Akaki found that sea levels at southern locations in the Sea of Japan, the Korean Peninsula, Indochina and Malaysia had been falling for 40 years, he said.

Suphat said the sea level in the Andaman Sea might also be falling because it occupied the same latitudes as the Gulf of Thailand.

 Suphat, now a water and environment expert at Team Consulting Engineering, said the land subsidence reported in many coastal areas of the gulf was the consequence of human activity, including over-consumption of ground water.

Erosion plays a crucial role in land emergence and subsidence, he said.

Although climate change would not cause sea levels to rise in the Gulf of Thailand, Suphat warned against ignoring concerns about the impact of rising global temperatures.

Careful analysis rather than panic is in order, he said.

"The climate change panel did not deceive us or exaggerate. Its scientific findings are just based on the environment of their scientists, most of whom live in Europe," he said.

 Since 2001 the panel has been reporting global sea levels will rise between 11 and 28 centimetres by 2100, and that the rate is accelerating. The panel was set up in 1998 by the World Meteorological Organisation and the United Nations Environment Programme.

Pennapa Hongthong

The Nation