Higher risk of haze in Singapore from June to October due to El Nino, Indian Ocean Dipole
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The Meteorological Service Singapore also forecast El Nino conditions to develop from June to July this year.
ST PHOTO: KELVIN CHNG
SINGAPORE – There is an increased risk of Singapore being affected by haze from June to October, as El Nino is expected to develop and coincide with another climate phenomenon, the Indian Ocean Dipole.
Warmer and drier conditions are also expected in the coming months due to both climate phenomena, the National Environment Agency (NEA) and Meteorological Service Singapore (MSS) said in a statement on May 29.
The period between March and May 2027 could be warmer than usual too, as this is when El Nino weakens and has the highest impact on temperatures.
Singapore experienced an El Nino and a positive Indian Ocean Dipole together in 2015 – resulting in one of the region’s most severe haze crises on record – with rainfall from June to September that year about 35 per cent below the long-term average. A positive Indian Ocean Dipole is one of the three phases of the Indian Ocean Dipole phenomenon, alongside the neutral and negative phases.
The Republic experienced its last heatwave in April 2016.
The two authorities said the 28 government agencies under the Haze Task Force are ready to implement measures if air quality here is affected by transboundary haze.
According to MSS, there is an over 80 per cent chance of El Nino conditions developing, with the phenomenon forecast to emerge from June to July.
El Nino is a naturally occurring climate pattern associated with changes in both the ocean and atmosphere in the equatorial Pacific Ocean, including an abnormal warming of surface waters in the eastern Pacific.
El Nino events tend to have the greatest influence on Singapore’s rainfall during the south-west monsoon season from June to September, increasing the likelihood of dry conditions. The weather phenomenon also brings warmer temperatures to Singapore.
An Indian Ocean Dipole is similar to El Nino but develops in the equatorial Indian Ocean, typically ending by December or January. A positive Indian Ocean Dipole is expected to develop in July or August, bringing drier and warmer weather to Singapore and its surrounding regions. Cooler sea surface temperatures in the eastern Indian Ocean result in less cloud formation, contributing to the drier conditions.
“With an expected El Nino and a potential positive IOD (Indian Ocean Dipole), the dry season this year could be more intense and prolonged compared with recent years and extend into October,” said NEA and MSS.
Drier and warmer conditions are conducive to the development of peatland and vegetation fires, which could escalate the hot spot and smoke haze situation in the surrounding region from June, particularly in fire-prone areas, the two agencies said. They added: “This will increase the risk of transboundary haze affecting Singapore and the region.”
On May 7, Minister for Sustainability and the Environment Grace Fu warned that a “Godzilla” or super El Nino could trigger more intense forest fires and haze in South-east Asia later in 2026. It emerges when the central equatorial Pacific Ocean’s surface temperatures exceed 2 deg C above the long-term average. An ordinary El Nino occurs when the sea surface temperature rises by 0.5 deg C.
The public should refer to NEA’s website, the myENV app and www.haze.gov.sg for advisories on the haze situation, the two agencies said.
They should use the one-hour PM2.5 concentration as an indicator of current air quality when planning for outdoor or strenuous activities over the next few hours, and check the 24-hour PSI and accompanying health advisories when planning for activities for the next day, said NEA and MSS, adding that the public should ensure air purifiers at home are working properly.
