SINGAPORE: A pall cloaked Singapore on Friday (Aug 26) as haze from central Sumatra was blown in by the prevailing westerly winds, according the National Environment Agency (NEA).
Several people took to social media and called in to Channel NewsAsia to say that they detected a burning smell in various parts of Singapore. Readings on the 24-hour Pollutants Standards Index (PSI) crept into the Unhealthy range from 4pm, and was highest in the west at 7pm at 114.
Cloudy skies seen at Clarke Quay at around 10.25am. (Photo: Xabryna Kek)
Hazy skies seen over western Singapore on Friday (Aug 26) morning.
The 1-hr PM2.5 readings, which peaked at 216 µg/m3 in the West at noon have since dropped to about 59 to 84.
The PSI incorporates six types of pollutants - sulphur dioxide, particulate matter that is 2.5 micrometres in diameter or smaller (PM2.5), particulate matter that is 10 micrometres in diameter or smaller (PM10), ozone, nitrogen dioxide and carbon monoxide. Of the six, PM2.5 is considered particularly hazardous as the small size of the particles enters the human lungs more easily.
PSI TO BE IN UNHEALTHY RANGE: NEA
In a statement at around 11.50am, NEA said the haze was likely to have been blown in by westerly winds over Singapore. A total of three hotspots were detected in central Sumatra on Thursday with localised smoke plumes were visible, the authority said, adding that the low hotspot count was due to cloudy conditions.
By 6pm, NEA said the overall PSI for the next 24 hours is forecast to be in the Unhealthy range and that the 1-hr PM2.5 concentration is expected to fluctuate between Elevated and High.
A view of central Singapore on Friday. (Photo: Calvin Oh)
Haze blanketing Singapore, as seen from Beach Road. (Photo: John Choo)
Grey skies above Tampines.
National University of Singapore Assistant Professor of Geography Winston Chow said the haze was caused by a change in wind direction from southerly or southwesterly to westerly winds on Friday morning, combined with hotspots in central Sumatra that generated smoke plumes that were carried over the Malacca Straits.
He also said how long the haze would last in the immediate term would depend on the wind direction as Singapore would be affected by plumes from central Sumatra as long as there were westerly winds. "That said, it’s forecast that there is a likely change in wind direction over the next few days to a more south or southeasterly direction, which should improve air quality as long as there are no hotspots and smoke plumes from South Sumatra or West Kalimantan."
7,000 PERSONNEL ON THE GROUND TO FIGHT FIRES: INDONESIA
Indonesia's National Disaster Mitigation Agency (BNPB) said on Friday evening that the haze which appeared in Singapore skies was from forest fires in Indonesia's Riau province.
In a statement, BNPB said that monitoring posts on the ground had reported 67 hotspots in the province, with most of the hotspots from the Rokan Hilir district.
BNPB said that efforts to put out the fires in Riau were continuing, and that more than 7,000 personnel were on the ground to extinguish the flames. Assets to conduct water bombing, including three helicopters and two Air Tractors aircraft, have been deployed. One Casa aircraft has been mobilised for cloud seeding operations.
The Chief Executive Officer of NEA has written to his Indonesian counterpart to register concern. "NEA urged Indonesia to continue taking the necessary actions to prevent and mitigate the fires during this dry season, and asked for an update on the situation in Sumatra and Kalimantan," the agency said.
Back in March this year, when a burning smell was detected in some parts of Singapore, the NEA said it could have been caused by some local vegetation fires.
It added that fires and some wind convergence over Singapore could have also contributed to the deterioration in the air quality in some parts of the island.
NEA said on Friday that the health impact of haze was dependent on one’s health status, the PSI level, and the length and intensity of outdoor activity.
"Given the air quality forecast for the next 12 hours, everyone can continue with normal activities. Persons who are not feeling well, especially the elderly and children, and those with chronic heart or lung conditions, should seek medical attention."