Sensitivity of hydrometeor profiles and satellite brightness temperatures to model microphysics for MCSs over land and ocean: Model comparison using EOF analysis and implications for rain and latent heat retrievals

The impact of model microphysics on the relationships between microphysical variables and derived satellite microwave brightness temperatures (T _B's) and on the retrievals of microphysical variables was using a three-dimensional, nonhydrostatic, adaptive-grid cloud model to simulate two mesoscale convective systems, one over land and one over ocean. Four microphysical schemes (each employing 3-ice bulk parameterizations) were compared in both convective and stratiform precipitation using Empirical Orthogonal Function analysis.; The validity of the microphysical schemes suggests that over land the model microphysical schemes produce too much reflectivity aloft and too rapid a decrease in reflectivity from the melting level to the surface, and over ocean the simulations produced more graupel and not enough rain.; Model microphysics had a noticeable impact on the relations between the hydrometeor structure and T_B's. Classified in terms of T_B 's, the microphysical schemes produce significantly different mean vertical profiles of cloud water, cloud ice, snow, vertical velocity, and latent heating, especially in stratiform clouds. Vertical velocity and latent heating in simulated stratiform clouds were not well correlated with T_B's for any of the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) frequencies. Differences in the amount of supercooled cloud water produced in the various schemes accounted for much of the variation in T_B relations.; The uncertainty in retrieving hydrometeor and latent heating profiles for passive microwave measurements has been examined quantitatively. The four microphysical schemes exhibited analogous uncertainties in retrieving rain and graupel, but very different uncertainties in retrieving cloud water, cloud ice, and snow. The uncertainty in retrieving latent heating appears to be related to the insensitivity of TMI frequencies to cloud water, cloud ice, and snow.; Structural differences in hydrometeor and latent heating profiles of 15–60% and 60–140%, respectively, correspond to only a few degrees of difference in T_B's at TMI frequencies. After the model outputs are area-averaged over 42 x 42 km2, the low resolutions exhibit a large decrease in the structural differences in convective region, but a slight decrease in stratiform region. The ability to detect these hydrometeor species is needed to improve the retrieval of latent heating in convective systems.