Operational C-band radar refractivity measurement: A feasibility study

A collaboration between the UK Met Office and the University of Reading has been undertaken to determine the feasibility of obtaining radar refractivity fields from operational magnetron-based C-band radars. As radar refractivity is strongly linked to humidity, the possibility of deriving two-dimensional fields from pre-existing radar networks shows potential for the assimlation of such observations into NWP models. However, significant challenges exist in deriving refractivity from the operational radar due to the relatively short wavelength and frequency drifts of these systems. The work to be presented concerns the technical difficulties associated with deriving refractivity fields from such radars and the steps implemented to overcome these problems. Examples of refractivity fields obtained during this study are presented and the associated limitations discussed.