Air quality in parts of Singapore deteriorated to the most severe category on its pollution scale on Wednesday, as thick smoke drifting from wildfires burning across Indonesia blanketed large parts of Southeast Asia.
The one-hour reading of fine particulate matter concentration reached 288 in the west of Singapore during the afternoon, well above the threshold of 251 that marks the top of the city-state’s four-tier air quality index, categorized as “very high.”
Singapore, Kuala Lumpur and the Indonesian city of Medan in Sumatra ranked among the three most polluted cities in the world as of Wednesday afternoon, according to data compiled by IQAir, underscoring how widely the haze has spread beyond its source.
The smoke originates largely from Indonesia, which is in the grip of its most severe wildfire season in roughly 11 years. Prolonged dry conditions, worsened by a strong El Niño pattern, have allowed land-clearing fires to burn out of control, sending noxious smoke across the Strait of Malacca and into neighboring countries.
The haze has already forced several Malaysian states to shut down schools, and authorities across the region have reported a rise in respiratory complaints as residents are exposed to prolonged periods of hazardous air.
The crisis revives a recurring seasonal problem for Southeast Asia, where transboundary haze from Indonesian land and forest fires has periodically disrupted daily life, air travel and public health across Singapore, Malaysia and beyond, with this year's El Niño-driven dryness making the fires especially difficult to contain.
