Precipitation and Latent Heating Distributions from Satellite Passive Microwave Radiometry. Part II: Evaluation of Estimates Using Independent Data

摘要: Rainfall rate estimates from spaceborne microwave radiometers are generally accepted as reliable by a majority of the atmospheric science community. One Tropical Measuring Mission (TRMM) facility rain-rate algorithms is based upon passive observations TRMM Microwave Imager (TMI). In Part I this series, improvements TMI algorithm that required to introduce latent heating an additional product described. Here, surface rain rate, convective proportion, and evaluated using independent ground-based satellite products. Instantaneous, 0.5°-resolution over ocean improved well correlated with radar estimate s( r 0.88 Tropics), but bias reduction most significant improvement earlier algorithms. The attributed greater breadth cloud-resolving model simulations support more consistent specific convective/stratiform separation method utilized. monthly 2.5°-resolution similarly reduced, comparable correlations estimates. Although amount data limited, TMI-estimated profiles compare favorably instantaneous dual-Doppler observations, time series those derived rawinsonde analyses. Still, some biases in profile shape evident, these may be resolved (a) contextual information brought estimation problem and/or (b) physically representative databases supporting algorithm. A random error appears levels determined comparisons collocated radar. Error modifications for nonraining situations will required, however. Sampling represents only portion total estimates; remaining systematic errors arising physical inconsistency nonrepresentativeness cloud-resolving-model-simulated