Identification of Synoptic Scale Circulation Patterns Affecting Dust Phenomenon Occurrence in Bushehr Province

Dust storms create hazards for human society in numerous ways and are particularly significant to people who are living in the dust belt which stretches in the west to the southwest of Iran. Numerus studies have been performed by scholars in various ways on this phenomenon which is still hot research topics throughout the world because of its critically importance and adverse consequent impacts. The present research purpose is to identify the synoptic scale circulation patterns responsible for dust storm in Bushehr province. The studied stations include Bushehr synoptic Station, Deylam, Dayyer and Jam during a 17-year (2001-2017). Meteorological data (code 06 to identify the dust locality) and data from the ECMWF are used. Also, sea level pressure, Uwind, Vwind component, vertical velocity and wind velocity at 10 m as the meteorological parameters are considered. The number of recorded dusty days across all studied stations were 177 events during the study period. The results revealed that six synoptic scale circulation patterns influence Bushehr province in dusty days from 2001 to 2017. These patterns include one spring pattern, three winter and two summer patterns. Each pattern contribution to the occurrence of dust in Bushehr province was as follows: The spring pattern was 39%, the first, second and third winter patterns were 7.6%, 9.9%, 9.3% respectively, and also the first and second summer patterns were 18% and 16.2% respectively.