Simulations of X band thunderstorm airborne radar observations

This paper deals with simulations of thunderstorm airborne radar observations at X band (f = 10 GHz), the frequency used by the meteorological radars of civil aviation. For this study, a radar simulator using NEXRAD data is elaborated. The various problems affecting X band (attenuation and non Rayleigh scattering) can lead to an underestimation or a false estimation of hazards. They are illustrated by a real case of severe tornadic storm in Oklahoma. It is shown that the first Mie mode of hailstones limits the large hail area detection because hail can be mistaken with non dangerous heavy rain. In addition, the problem commonly encountered with a large radar beam aperture and for long distance of observations is addressed. Ground clutter is shown to contaminate the signal of reflectivity.