Hong Kong experienced its warmest ever start to winter on Saturday, but dangerously high levels of pollution forced the city’s environmental watchdog to warn children, the elderly, and people with heart or respiratory problems to stay indoors.
Officials said the level of air pollution posed a “very high” health risk in several spots in the New Territories, while the level in other areas was deemed “high”.
Based on the Chinese calendar, the winter season started this weekend, and the 30.2 degrees Celsius (86 degrees Fahrenheit) temperature recorded on Saturday afternoon was the warmest for the time of year since records began in 1884.
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The Environmental Protection Department recorded higher than normal pollution levels on Saturday, with the Air Quality Health Index for Tuen Mun, Tung Chung and Southern district reaching “very high” levels of risk as of 5pm.
The pollution index for Central, Mong Kok, Causeway Bay, Sha Tin, Sham Shui Po, Kwun Tong, Yuen Long, Kwai Chung, Tseung Kwn O, Western district, North district and Tap Mun also reached “high” levels.
The air quality index is based on the cumulative health risk caused by average concentrations of four air pollutants: ozone, nitrogen dioxide, sulphur dioxide and particulate matter. The index is reported on a scale of 1 to 10+, with scores grouped into five health risk categories: low, moderate, high, very high, and serious.
With a health risk category in the “very high” range or above, authorities advise children, the elderly and people with existing heart or respiratory illnesses to keep physical exertion and outdoor activities to a minimum, especially in areas with heavy traffic.
The Hong Kong Observatory forecaster that the weather in the city would remain fine and dry, with slightly cooler temperatures in the morning and at night over the next few days.
As of 4pm, tropical storm Atsani was centred about 110km west of the Taiwanese city of Kaohsiung. It was forecast to move slowly at first and then gradually weaken across the northeastern part of the South China Sea.
The department also advised employers to assess the risk of working outdoors, and to take appropriate preventive measures to protect the health of their staff, such as reducing outdoor physical exertion and the time they spent outside.
Sunday’s weather was expected to be fine with sunny intervals during the day. Temperatures were forecast to be between 22 and 27 degrees, with moderate north to north-easterly winds.