The word ‘Monsoon’ is derived from the Arabic ‘mausim’ terrain for season. Monsoons are like an intense sea breaze and blow for approximately six months from the northeast and six months from the southwest, especially in southern Asia and parts of Africa. Summer monsoons have a dominant westerly component and a strong tendency to converge, rise, and produce rain. Winter monsoons have a dominant easterly component and a strong tendency to diverge, subside, and cause drought. Both are the result of differences in annual temperature trends over land and sea.
The Iran is Located in Middle East, bordering the Gulf of Oman, the Persian Gulf, and the Caspian Sea. The Iran have a terrain rugged, mountainous rim; high, central basin with deserts, mountains; small, discontinuous plains along both coasts.
The study of rainfalls data of the several Irannian cities on June to Sep. during 1960 through 1990 show that, because of the Kuhhayes Bashakerd , Kuhha Jebal Barez and Hamun Jazmurian in southeast of Iran, that region have monsoonal climate. Even, If the indian monsoon is strong that will especially affect in southern Dashte Lut and parts of Dashte Kavir. Therefore, the Iran climate is mostly arid or semiarid, subtropical along Caspian coast and monsoonic in the southeast.
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