A low-level jet in eastern Iran: a possible factor in dust events in the region
نویسندگان
1 Earth, Ocean and Atmospheric Science Department, Florida State University, Tallahassee, FL 32306, USA
doi
10.22059/jdesert.2015.56473چکیده
One of the world's major mineral dust source regions lies along the border between Iran and Afghanistan. In this studyit is hypothesized that a low-level jet may play in role in generating the intensity of this source region. The presence of alow-level jet east of the Seistan mountains is documented here for the first time. The jet exists mainly from May toSeptember and has a core at 850 mb. Maximum speeds are at 18 UTC and 0 UTC and occur in July-August. In the meanthe core speed attains 20 ms-1 in those months. The jet attains a maximum at night, a minimum during the day. However, the vertical motions associated with it do not fluctuate greatly over the course of the day. The development of the jet during a dust outbreak in 2002 is also described. It arises a day or so before the outbreak and disappears as the outbreak ends.