Evaluation of meteorological airborne doppler radar. Part I: Dual-doppler analyses of air motions

This is the first of two papers which evaluate the capabilities of airborne Doppler radars for atmospheric sciences research. In Part I, we will evaluate the collection and analysis of dual-Doppler data using dual airborne Doppler data, and using combinations of airborne and ground-based Doppler data. In Part II, we will evaluate the capability of the airborne Doppler radar to collect predominantly vertically pointing data as a part of a triple-Doppler radar analysis. This paper presents an evaluation of dual-Doppler radar observations of a convective storm. The storm was observed simultaneously by airborne and ground-based Doppler radars. Comparative analyses are performed which make use of dual airborne observations, dual ground-based observations and combined airborne and ground-based observations of the storm. Analysis of these observations shows that airborne Doppler radar produces observations with an accuracy similar to that provided by ground-based. It is suggested that the process of multiple-Doppler analysis produces effects that contribute strongly to the observed differences between the airborne and ground-based analyses. It is also noted that temporal effects, predominantly storm evolution, produce differences between the airborne and ground-based Doppler analyses. The airborne Doppler is seen to be a viable tool for atmospheric sciences research.