Dual-frequency retrieval of cloud liquid water content

We present an approach that utilizes radar attenuation to retrieve cloud microphysical properties. The use of radar attenuation instead of backscatter to retrieve cloud microphysical properties overcomes the sensitivity of conventional radar backscattering to large, precipitation particles, rather than the small, cloud particles that are of principal interest. We have developed an algorithm that takes advantage of large amounts of spatial data to overcome the low signal-to-noise ratio problem in observed radar attenuation. The developed approach is evaluated using observations from various field campaigns of the DOE Atmospheric Radiation Measurement program. It has been demonstrated that the attenuation-based approach is able to provide unbiased retrievals of liquid water content for both continental and maritime clouds under a large variety of conditions.