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Figure 3. Rainfall areas discriminated by the DCD algorithm applied to SSM/I image of Figure 1. 
Figure 4. Microwave signature at SSM/I frequencies of selected precipitation over land. 
Figure 4 shows the microwave signature at 19. 22. 37, and 85 GHz for the rainfall events 
over land, identified in Figure 3. The low values of T B 's (less than 180 K) at 85 GHz and 37 GHz correspond 
to the convective cores of the observed storms. Note how the 19 and 22 GHz T B 's show a smaller range of 
values with respect to the 37 and 85 GHz T B 's: this depends on the fact that the higher frequency T B 's are 
strongly modulated by precipitating ice, that exhibits high variability within a convective cloud system.