تاثير سرمازايي باد بر ميزان راحتي انسان در مناطق مختلف ايران

The Effect of Wind Chill on Human Comfort in Different Parts of Iran A. R.Ghasemi\

Variations of meteorological conditions can significantly influence human comfort. The present study evaluates the effect of the combination of air temperature and wind velocity on human comfort for 22 stations in Iran. The results indicate that for the eastern half of the country the effect of wind on heat loss from exposed skin of humans is greater than the western parts. Because of the warmness of the air temperature during October and November, the effect of wind chill on heat loss from skin is not considerable. During December, the effect of wind on decrease of air temperature in most stations is high, varying from 0.5 °C (in Arak) to 2.5 °C (in Hamedan). The maximum heat loss from skin is observed in January and February. In these months the skin temperature is much lower than air temperature (for about 1 -3 °C) in most parts of the country. Maximum heat loss from skin is observed in western half of the country (mountainous regions of Alborz and Zagros). The mountainous regions of the Alborz and Zagros are the most affected regions in the country, where the harmful effects of wind chill on human life are high in these regions. In March, the wind speed is high and in spite of increase of air temperature, the effect of wind on decrease of air temperature is considerable, varying from 0.5 °C (in Rasht) to 3 °C (in Hamedan). The best way to decrease harmful effects of the wind chill is paying attention to warnings of the Meteorological Organizations and using suitable clothing in cold and windy days. In natural open space the use of the windbreaks is the best way to decrease the harmful effects of wind chill.