RESUMEN
Dwelling in cities and city development together with quick increase of population and development of industrial activities with unplanned consumption of fossil fuel have intensively increased pollutions with consequences which will cause different diseases in short period, will lead to some climatic oscillations and its environmental effects such as the change of desirable periods in view of comfort climate in long period. The objective point of view of this research was to study the climate in Shiraz and its effect on comfort conditions for human physiology. In this research, using 55-year climatic data [1952-2006], the relative humidity and temperature through the application Guni comfort climatic model, the desirable months for the comfort of human physiology have been determined in the five 11-year periods and the linear process of these changes have been estimated for the next 11 years. The results of this research show that the temperature trend in Shiraz station is increasing and most months have heating process in a way that it is expected that in the coming future, the cold months will have more favoring conditions for physiological comfort of residents and correspondingly in the warm months, heating tension will have remarkable increase