Abstract:

Based on the diurnal meteorological data from 34 ground weather stations from 1981 to 2010 in Chongqing region, the temporal and spatial characteristics of the number of human comfortable days were analyzed in terms of human comfortable index models and assessment standards of climate impact, and the methods of a linear regression, a M-K mutation, a wavelet theory and an EOF analysis were employed. The results show that the annual mean of the number of human comfortable days are 199 d in Chongqing area. The main comfortable seasons are spring and autumn, and both account for 71% of the year. The inter-annual changes of human comfortable days are significant, and it is in a rising trend in general. There are two periodic oscillations of 4 years and 7-8 years. The hot uncomfortable day is in an ascending trend, while the cold one is in a descending trend. The mean annual human comfortable days and hot uncomfortable days are greater in the southwestern Chongqing and northeastern Chongqing than in the other areas of Chongqing and there are seasonal variations, while the reverse is true for the cold uncomfortable days.

Key words: Human comfortable days, M-K mutation, EOF (Empirical Orthogonal Function) method