Jakarta rain caused by rising sea temperature

Prodita Sabarini, The Jakarta Post 15 May 09;

A rare increase in sea temperatures has caused a prolonged rainy season and the recent torrential rain that flooded North Jakarta, a Meteorology and Geophysics Agency (BMKG) official says.

The BMKG previously pre-dicted the wet season would end around mid-April in the northern area of Jakarta and mid-May in South Jakarta.

Already mid-May, this week, a flash flood burst a dam in Pluit, North Jakarta, after heavy rain in the area.

The flash flood inundated six subdistricts in the area, including the affluent residential complex of Pantai Mutiara.

The head of climatology and air quality analysis at BMKG, Soetamto, said the agency had failed to predict the heavy rain due to a rare increase in the sea temperature by 1 degree Celsius.

"The Java Sea and the sea in the southern part of Java, in the third and fourth weeks of April, experienced a temperature increase of 1 degree Celsius," Soetamto said.

The Java Sea lies between the islands of Java and Kalimantan to the north, Sumatra to the west and Sulawesi to the east.

Soetamto said the temperature rise caused high evaporation, which resulted in continued heavy rainfall during May.

Soetamto said the agency pre-dicted the rain would continue to pound North Jakarta until the end of May, while South Jakarta was likely to see the start of the dry season in June.

He said that annually, the sea temperature in Java dropped in April in the lead-up to the dry season.

During the last 15 years of monitoring, a rise in the sea temperature by 1 degree has occurred only once, in 2005.

Soetamto did not comment when asked whether the phenomenon was related to global climate change.

However, he said this was "a very rare case".

"That's why people were surprised to experience rain in the middle of May," he said.