Cheung Chi-fai – Updated on Jul 25, 2008 – SCMP
The rainy day blues of last month now seem a distant memory, dispelled by Hong Kong’s recent run of blue skies and clear views.
With temperatures over 30 degrees Celsius and ambient air pollution readings hovering between low and medium, visibility has been excellent. At Chek Lap Kok, which is often shrouded in smog, the visibility yesterday was more than 35km.
The fine spell is not unusual for July. Last year, July saw a 20-day spell of fine, clear weather due to an exceptionally strong ridge of high pressure over southeastern China.
The Environmental Protection Department said prevailing southerly winds and the convection effect from the hot weather had helped disperse pollutants and bring fresher air from the sea this month.
“Apart from the fine weather, the measures implemented over the past years have also contributed to better air quality,” a department spokesman said.
However, the department’s own figures show that readings from general pollution-monitoring stations have been high – meaning an air pollution index of 100 or more – for 499 hours, up 12 per cent on the same period last year. The number of hours of high readings from roadside pollution-monitoring stations is up 15 per cent on the same period last year, at 497 hours.
The department said the public should interpret air pollution data cautiously because it only revealed a partial picture of air quality, which was affected by various factors.
Tsang Kam-lam, of the Hong Kong Productivity Council, which has been promoting clean production methods among Hong Kong manufacturers in the Pearl River Delta, said he believed the blue skies had little to do with the closure of factories across the border because of mainland policy changes and rising operating costs. “The good weather is a direct result of southerly winds which visit us every summer,” he said.
He also said he had not heard of any delta factories being required to adjust their production ahead of next month’s Olympics.
Speaking after a forum at the Hong Kong Book Fair, Undersecretary for the Environment Kitty Poon Kit said the government would continue to strengthen co-operation with Guangdong on improving air quality. She said both sides would study emission targets after 2010, when the current agreement to cut major pollutants expires.