Assessment of thermal comfort in urban open space (case study: Qom province)

Document Type : Original Article


Department of Air Pollution, Atmospheric Science and Meteorogical Research Center, Tehran, Iran


Open spaces are the most important area of human social exchange, which may be affected by a wide range of factors. Encouraging individuals for being outdoor is one of the main factors for economic, social and political development in the cities. Studying and determining the limitations and climate hazards along with noticing their hidden ecological potentials in different seasons of the year should be taken into account for different provincial planning. It can also play a key role in urban and zone planning. For this reason, the objective of this research was the determination of the thermal comfort of people in Qom Province’s outdoor.
Meterial and methods:
In this research, predicted mean score (PMV), equivalent physiological temperature (PET) and human thermal comfort in outdoors of Qom Province were analyzed. For this purpose, five parameters including temperature, relative humidity, wind speed, water vapor pressure and cloud coverage in three weather stations of Qom, Kahak, and Salafchegan were extracted in a 12-year period of time (2004-2017). The data were then transferred to RayMan software in different time scales and then PET and PMV were calculated and analyzed.
Results and disscussion:
Our analyses showed that climate comfort period in this province was limited to two separate periods, which is simultaneous with the transition of the warm period into a cold one or vice versa. This situation contains 7.92% of the year; the first period is during April and May, while the second period occurs in October. These months were the best times for environmental activities in Qom Province. Because of geographic variety and topographic distribution, the inconsistency of the thermal situation can be clearly observed in this research. Mountainous places were faced with cold tensions in 50.27% of the year and low altitude places were faced with warm tensions in 51.63% of the year. Monthly analysis showed that the limiting factors of thermal comfort in the central and eastern part of the province were medium and high thermal tensions in May, June, January, August, and September, while the only limitation of mountainous cities was the cold tensions happening in November, December, January, February, and March. The results showed that the effects of altitude and topographic distribution caused climate variations in this zone, which makes every ecological climate situation possible to happen in Qom province.
Results of this research showed that the output of eco-climate factors of PET and PMV has the capability of clarifying comfort and discomfort periods in Qom Province. Besides minor differences, it can present homogeneous phenomenon of comfort climate in this city and provide better information for planning and management purposes. In general, according to different methods, factors, and data analysis, an integration of different factors should be considered to achieve our goals.


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