High-power radar for meteorological stuides in clear air

A very high-sensitivity S band radar capable of detecting targets with radar cross-section of 5 × 10¿10 m2 of reflectivities of 2 × 10¿15 m¿1 at a range of 10km has recently been brought into operation for meteorological studies of the clear atmosphere. The paper outlines the constraints set by the meterological requirements, and describes the radar which has been assembled to meet them. Examples are presented of clear-air echoes obtained both from extensive horizontal layers at hieghts up to 3 km, and also from high-altitude clear-air turbulence.