Dry weather over the coming week could increase the risk of transboundary haze affecting Singapore if fires intensify in parts of Indonesia.
Minister for Sustainability and the Environment Grace Fu said on 5 August that the Meteorological Service Singapore expects dry weather across the region during the week ahead.
The areas of concern include Kalimantan and southern Sumatra, where hotspots and smoke plumes have been detected.
However, this does not mean that Singapore will definitely become hazy next week.
Smoke haze had recently drifted from Kalimantan into Sarawak, but the prevailing winds were not carrying the pollutants towards Singapore as of 5 August.
In other words, this is a warning to keep an eye on the situation, not a signal to start panic-buying every N95 mask in NTUC.
ASEAN Has Raised Its Haze Alert to Level 2
The ASEAN Specialised Meteorological Centre, or ASMC, raised the haze alert for the southern ASEAN region to Level 2 on 3 August.
Level 2 means that there is an increasing risk of transboundary haze in the region. It is one step below Level 3, which indicates a high risk of severe transboundary haze.
According to ASMC, Level 2 conditions can involve escalating hotspot activity, persistent dry weather and moderate to dense smoke haze being observed for at least two consecutive days.
On 1 and 2 August, satellites detected 185 and 371 hotspots respectively in Kalimantan. Another 26 and 11 hotspots were detected in Sumatra on those two days.
By 6 August, widespread hotspots were being detected in West Kalimantan, while moderate to dense smoke was drifting northwards into western Sarawak.
Smoke plumes were also observed over other parts of Kalimantan and southern Sumatra.
Why Dry Weather Makes the Haze Risk Worse
Singapore and the surrounding region are currently experiencing Southwest Monsoon conditions, which generally coincide with the dry season in southern ASEAN.
The first half of August is expected to be drier than the previous fortnight, with below-average rainfall forecast over most parts of Singapore.
Several days of fair and occasionally windy weather are also expected, particularly during the second week of August.
Singapore’s daily maximum temperatures are forecast to reach between 33°C and 34°C on most days.
Dry conditions allow vegetation and peatlands to become more flammable. Fires can then spread more easily and produce larger amounts of smoke.
Whether that smoke reaches Singapore depends partly on the location and intensity of the fires, as well as the direction of the prevailing winds.
El Niño conditions are also present and are expected to strengthen over the coming months. El Niño typically increases the chance of hotter and drier weather across Singapore and the surrounding region.
ASMC expects below-normal rainfall to persist across much of southern ASEAN from August to October, potentially extending the period of elevated haze risk.
Singapore Is Ready to Activate Its Haze Plans
Ms Fu said government agencies under Singapore’s Haze Task Force are prepared to introduce their respective measures if the country’s air quality deteriorates.
Singapore’s national stockpile of masks is sufficient, while schools, preschools, residential facilities and care facilities have been equipped with air purifiers.
Authorities have also stepped up public communications about the risk of haze and the protective measures that people and organisations can take.
For immediate outdoor plans, the public should monitor the one-hour PM2.5 readings. The 24-hour Pollutant Standards Index, or PSI, should be used together with health advisories when planning activities for the following day.
A PSI reading above 100 is considered unhealthy.
According to the Ministry of Health, healthy people generally do not need an N95 mask for short journeys between home, work or school.
People should reduce prolonged or strenuous outdoor activity when air quality reaches unhealthy levels. Children, elderly people, pregnant women and those with chronic heart or lung conditions may need to take greater precautions.
Updates are available through the NEA website, the haze microsite and the myENV application.
