Diagnostical and observational analysis of clear air turbulence over the middle east and Iran

Document Type : Research Article

Authors

1 Graduate Center, Shahid Sattari Aeronautical University, Tehran, Iran.

2 Space Physics Department, Institute of Geophysics, University of Tehran

3 Institute of Geophysics, University of Tehran

Abstract

Turbulence forecasting started in World War II when scientists and individuals in the field of aviation began attempting to correlate observed clear air turbulence events with large scale synoptic features. Encounters with significant turbulence or simply bumpiness in flight, are a major concern not only for passenger comfort but also for safe, efficient, and cost-effective aircraft operations. Clear air turbulence represents disorganized fluid motions in the form of micro scale eddies that can take place within cloud-free or limited cloud patches in the free atmosphere, which causes in-flight bumpiness of aircraft. This study aims to present two case studies and comparison of the report of clear air turbulence over center, east and south east crossings over Iran region. Regional weather predictions are carried out using an ensemble forecasting system. In addition, the initial and lateral boundary conditions are taken from the global forecast system. For each member of the ensemble system, two nested computational domains with spatial resolutions of 27000 meters and 9000 meters are used. Case study of the predicted clear air turbulence indicates the proper performance of the predicted meteorological parameters.

Keywords

Main Subjects

References

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Amirkabir Journal of Mechanical Engineering
Volume 53, Issue 7
October 2021
Pages 4203-4220

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