INDONESIA - Indonesia will begin cloud seeding to induce rain over Riau province as early as on Tuesday, officials say, as the smoke from forest fires returned to shroud parts of the province and neighbouring Malaysia, including Kuala Lumpur and Muar.
The skies are still clear in Singapore, but the National Environment Agency (NEA) says that the haze may return if the wind changes direction. Tuesday's air quality until 4pm is expected to be good to moderate.
NEA chief executive Ronnie Tay on Monday registered Singapore's concerns over a sudden spike in the number of hot spots in Sumatra in a letter to Mr Arief Yuwono, Deputy Minister at the Environment Ministry. He also extended Singapore's support and assistance to Indonesia.
The number of forest-fire hot spots in Sumatra rose sharply at the weekend.
On Monday, the PSI hit hazardous levels in parts of Riau, which affected several flights in the morning. For instance, the Pollutant Standards Index reading was 619 in Rumbai, north of provincial capital Pekanbaru.
Satellite readings showed 252 hot spots across Sumatra on Monday, with 167 in Riau. The province had 173 hot spots on Sunday, up sharply from 63 a day earlier.
In Malaysia, the Air Pollutant Index reading in places such as Malacca, Muar in Johor and Cheras in Kuala Lumpur was above 100, which is in the unhealthy range.
The return of the forest fires before October, when the dry season ends, had been anticipated.
But the sharp jump in the number of hot spots over the weekend came as a surprise, said Mr Heru Widodo, head of the weather modification team at the Agency for Assessment and Application of Technology (BPPT).
"We have not had the clouds to seed the past several days, but we should see them back above Riau on July 23 or July 24, according to the latest weather forecast," he told The Straits Times.
Forest fires sent pollution levels to record highs in Riau province and also Malaysia and Singapore last month.
After declaring the haze in Riau a national emergency, Jakarta took charge of efforts, including intensive cloud-seeding and water-bombing operations. Soldiers were sent in to help put out the fires. They were pulled back gradually after the emergency status was lifted on July 10.
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