Abstract: Based on the daily mortality data in Wuhan during June to August from 1998 to 2008 and the corresponding daily meteorological data, the impact of extreme high temperature in summer on population mortality was analyzed and the threshold value of extreme high temperature leading to excess death was determined. An assessment model was established by a stepwise regression method and it was verified, which was useful to assess the effect of high temperature on human health and predict the medical meteorological factors. The results show that the excess mortality in Wuhan can be quantitatively described. The extreme high temperature in summer has great impact on excess mortality, while air humidity, pressure and wind speed almost have no effect on it. The excess mortality rate is in an exponentially increasing trend with the increase of daily maximum air temperature, and its threshold value is 35.0 ℃. The excess mortality is 50.7% higher in “Hot day” than in “Non-hot day”. The excess mortality model is established by effective accumulated temperature with daily maximum temperature ≥35 ℃ and the daily average temperature. Using this model, a high temperature and wave process in 2003 is tested by a back substitution method. It has a good assessment effect for mortality cases during summer of 2007 and 2008. This model could be used to the operational application.

Key words: Extreme high temperature, Threshold value, Excess mortality, Quantitative assessment