A procedure for remotely estimating ice cloud effective particle size profiles using a combination of lidar signals, radar reflectivity, and average radar Doppler velocity has been applied to several months of data from the Atmospheric Radiation Measurement Program's Southern Great Plains site. On average, the data show a clear dependence of effective particle size on both temperature and ice water content, though considerable scatter is present in the retrieval results. The data are used to construct a size distribution parameterization based on a bimodal ice particle size-distribution model whose characteristics depend both on temperature and ice water content. The results are found to be consistent with the results of previous investigations based upon in situ measurements.