A study of summer human thermal stress in Hong Kong

An assessment of the summer human thermal stress for the period 1965-2003 for Hong Kong was conducted using the Heat Index (HI). At the diurnal scale, thermal stress reached the peak at around 2:00-3:00 pm (local time). Both the frequencies of persistant thermal stress episodes, and the onset and cessation of the stressful period demonstrated inter-annual variations. The extension of a strong ridge of high pressure from the Pacific to south China or tropical cyclones inducing subsidence creates an extreme thermal stress associated with the onset and duration of the discomfort period.