The director of the department's Geology Office, Lerdsin Raksasakulwong, said yesterday Bangkok faced flooding this year that could be every bit as severe as the devastation that hit the capital 70 years ago.

Lerdsin, an expert in soil, said the map showed areas in 51 provinces were at risk over three levels. Areas coloured red, yellow and green could experience landslides following 100 millimetres, 200mm and 300mm of rain, respectively, he said.

Lerdsin said people could get useful information at the website www.dmr.go.th.

Meanwhile, the Meteorological Department's website, www.tmd.go.th, which had been warning about the El Nino and La Nina effects since January, was now saying that a mild La Nina effect had already occurred.

Thanawat Jarupongsakul, a climate-change expert from Chulalongkorn University's Faculty of Science said the floods in Uttaradit were a result of changes in global climate, which are directly related to global warming.

La Nina would cause more rains in Thailand and neighbouring countries, he said.

With typhoons increasing by 10-20 per cent and becoming more severe, serious floods were likely in every part of the country from July to October, Thanawat said. Bangkok was at high risk of severe flooding similar to 1942 and 1953 as typhoons might come directly into the Gulf of Thailand.

Thanawat warned of diseases arriving with the climate change such as mutated bacteria. Epidemic diseases could spread and extinct diseases could reappear because of more rains.