The Chilbolton 3-GHz Advanced Meteorological Radar (CAMRa), which is mounted on a
fully steerable 25 metre dish, can provide three-dimensional information on the presence of
hydrometeors. We investigate the potential for this radar to make useful measurements of
low-altitude liquid water cloud structure. In order to assess the cloud-height assignment
capabilities of the 3-GHz radar, low-level cloud-top heights were retrieved from CAMRa
measurements made between May and July 2003 and compared with cloud-top heights
retrieved from a vertically pointing 94-GHz radar that operates alongside CAMRa. The
average difference between 94-GHz and 3-GHz radar derived cloud-top heights is shown to
be -0.1±0.4 km. In order to assess the capability of 3-GHz radar scans to be used for
satellite-derived cloud-top height validation, Multi-angle Imaging SpectroRadiometer
(MISR) cloud-top heights were compared with both 94-GHz and 3-GHz radar retrievals. The
average difference between 94-GHz radar and MISR cloud-top heights is shown to be
0.1±0.3 km while the 3-GHz radar and MISR average cloud-top height difference is shown
to be –0.2±0.6 km. In assessing the value of the CAMRa measurements, the problems
associated with low reflectivity values from stratiform liquid water clouds, ground clutter,
and Bragg scattering resulting from turbulent mixing are all addressed. We show that in
spite of the difficulties, the potential exists for CAMRa measurements to contribute
significantly to liquid water cloud-top height retrievals leading to the production of twodimensional
transects (i.e. maps) of cloud-top height
