NEA debunks online rumours that recent rain was caused by cloud seeding to clear haze

The skyline of central business district in Singapore obscured by haze on Sept 10, 2015.
The skyline of central business district in Singapore obscured by haze on Sept 10, 2015. ST PHOTO: ALICIA CHAN

SINGAPORE - The National Environment Agency (NEA) has debunked rumours that the Government is conducting cloud seeding operations to reduce the impact of haze for the Formula 1 race to be held this weekend.

The claims, which have been circulated online, also implied that the resultant rain was harmful, and urged people to keep away from "these chemically induced rain showers".

In a post on its website, the NEA on Thursday (Sept 17) said that these claims are untrue. It also clarified that "the Government has not been conducting cloud seeding and has no plans to do so".

Cloud seeding operations attempt to artificially induce rain by implanting clouds with suitable particles.

The NEA said that there are no reliable means to validate the effectiveness of cloud seeding in Singapore.

"Cloud seeding also requires existing clouds as it cannot generate rain out of thin and dry air. During dry seasons, cloud seeding is less effective due to the lack of suitable clouds for seeding," it said.

"The small size of Singapore and the variability of winds also mean that the induced rain, if any, may not fall directly over our island."

Minister for the Environment and Water Resources Vivian Balakrishnan also posted on his Facebook a message to debunk the rumours. "NEA does not engage in cloud seeding and has no plans to do so," he said.

Recent rain showers have brought some relief to the haze conditions.

Air quality improved further on Thursday as the prevailing winds continued to blow from the southeast, said the NEA in a haze update at 1pm on Thursday. As at 1pm, the 24-hour PSI stood at 76-96, in the moderate range of 51-100.

For the rest of Thursday, the prevailing southeasterly winds are forecast to be maintained, and occasional slightly hazy conditions are expected, the NEA said.

The 24-hour PSI for the next 12 hours is expected to be in the high end of the moderate range but may enter the low end of the unhealthy range if unfavourable winds blow in haze from Sumatra, Indonesia.

Given the air quality forecast, healthy people should reduce prolonged or strenuous outdoor physical exertion. The elderly, pregnant women and children should minimise prolonged or strenuous outdoor physical exertion, while those with chronic lung or heart disease should avoid prolonged or strenuous outdoor physical exertion.

People who are not feeling well, especially the elderly and children, and those with chronic heart or lung conditions, should seek medical attention.

The NEA urged members of the public to refer to its websites at,, for more information and updates.

They can also follow the NEA's social media accounts and NEA Twitter @NEAsg, or download the myENV app.