Diagnostical and Observational Analysis of Clear air turbulence over Middle East in particular for Iran

Clear air turbulence (CAT) forecasting got its start in the World War II era, when scientists and individuals in the field of aviation first began attempting to correlate observed clear air turbulence events with large scale synoptic features. Although there is a large spectrum of eddy sizes in the atmosphere, from macro scale to micro scale, aircraft bumpiness is felt mainly for a range of eddy sizes between about 100 m and 1 km; larger eddies cause only slow variations in the flight path while the effect of very small eddies is integrated over the surface of the aircraft.This study is two case study and comparison of the report of CAT of center, east and south east crossings (Sector 4, 5 and 6) of the results of the IRIAF IT, Communication and Electronic Administration. Regional weather predictions are carried out using an ensemble forecasting system development for the WRF model. Perturbed initial conditions and different choices of physical parameterizations are used to generate ensemble members. In addition, the initial and lateral boundary conditions are taken from the global forecast system (GFS). For each member of the ensemble system, two computational domains of the nesting area are used with spatial resolutions of 27,000 meters, 9,000 meters. Case study of the predicted clear air turbulence indicates the proper performance of the predicted meteorological parameters.