PETALING JAYA: Warmer waters will persist from next month to September if the current El Nino phenomenon is followed by La Nina.
La Nina is the condition where the central-eastern tropical Pacific Ocean is cooler than normal whereas El Nino is a warmer than normal condition in that region.
Universiti Kebangsaan Malaysia climatologist and oceanographer Prof Dr Fredolin Tangang said there is a 50% likelihood that La Nina will occur.
Dr Tangang said the current El Nino has made waters warmer by 1°C in South-East Asian seas since October last year and this is expected to continue until May or June.
“April, May and June are crucial months for the corals because that is when the ocean surface temperature is higher and additional warming may exceed the threshold temperature for corals,” said Dr Tangang.
“During El Nino, winds over the region tend to be weaker and it is less cloudy, which increases the solar radiation absorbed by the surface.”
“Weaker winds also means less heat is extracted from the surface of the sea, causing heat to stay on the sea surface.”
He said that the water temperature around this region will likely return to normal if there is no La Nina.
But should La Nina happen in the Pacific after El Nino dies out, Dr Tangang said the warmer weather conditions will persist longer than usual in South-East Asian seas, until September or even October.
This increases the possibility of coral bleaching and dying.
Dr Tangang said this was what happened during the 1987/88 El Nino followed by 1989 La Nina and the 1997/98 El Nino which was followed by 1999 La Nina.
According to Prof Tangang, this year’s El Nino is considered a strong one but weaker than the one in 1997/98.
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