Zoning seasonal and annual heating and cooling requirements of Iran

One of the major factors that affect Iran’s climate is its location in different geographical latitudes and variety of uneven lands from one side and entrance of diverse synoptic systems during the year from the other side. One of the main parameters that determine climate of each region is temperature especially degree day. DD is difference between average temperature and temperature thresholds are selected according to the objectives of the research. depict and analyze average, seasonal and annual cooling degree-day through temperature thresholds of25,11 degrees and average, seasonal and annual heating degree-day of the country through temperature ether sholds of 25,14 degrees using Asfazary database(in database is university of Esfahan). This database includes average daily temperature in 44 years from 1962 until 2003 on cells with dimensions of 15*1 kilometers across the country. Therefore, average daily temperature in Asfazary database is an array with dimensions of 15992*7187 in which lines show time (day) and columns show place (cells equal to15*15 kilometers). Results demonstrate that the highest amount of CDD is from temperature thresholds of 11 in summer related to coasts of Oman Sea and Khuzestan Plain equal to (CDD= 600-750) and the lowest amount of it is from.Temperature thresholds of 25for the whole country in winter equal to(CDD= 0). The highest heating need is from temperature thresholds of 1 in winter and related to the north-west area and the altitude equal to(HDD= 600-750) and its lowest is in summer related to the whole country with temperature thresholds of 14 equal to (HDD= 0).