Haze in morning improves by evening

Straits Times 23 Sep 12;

Moderately hazy conditions returned to Singapore yesterday morning.

The Pollutant Standards Index (PSI) average hit a high of 58 at 7am yesterday and stayed in the "moderate" range until noon. By 7pm, though, the reading had gone down to 47.

Any PSI reading below 50 is considered "good", while a reading between 50 and 100 is in the "moderate" range.

The National Environment Agency's (NEA) website listed health advisories for people in the northern, eastern and western parts of Singapore, advising them to limit prolonged outdoor activity.

No health warnings were given for those in the central and southern parts of the island, except that unusually sensitive people - such as older adults or those with heart and lung diseases - should consider reducing activities requiring heavy exertion.

Yesterday's higher pollution levels came almost two weeks after the PSI hit a one-year high of 79 on Sept 7.

The NEA said last Monday that hot spot activities in southern Sumatra are expected to continue this week, due to dry weather. "Singapore may experience hazy conditions on some days when the winds blow from the south-west," said a spokesman.

The haze has become an annual occurrence, caused by farmers and logging companies in Indonesia - particularly in Riau, Sumatra, Kalimantan, Jambi and Aceh - burning forests to clear land for cultivation, between June and September, the region's dry season.