“…However, these channels have shown great potential for precipitating cloud characterization and for precipitation retrieval. The different penetration ability of these channels in the atmosphere can be exploited to analyze the vertical distribution of hydrometeors (Wang et al, 1989(Wang et al, , 1997Burns et al, 1997;Staelin and Chen, 2000;Ferraro et al, 2005;Hong et al, 2005Hong et al, , 2008Funatsu et al, 2007Funatsu et al, , 2009Laviola and Levizzani, 2011) and to obtain some criteria for the characterization of precipitation as weak, moderate, strong convective, or stratiform using the TB differences 17 , 13 , and 37 (corresponding, respectively, to the differences between the 183.31 ± 1 and 183.31 ± 7 GHz, 183.31 ± 1 and 183.31 ± 3 GHz, 183.31 ± 3 and 183.31 ± 7 GHz channels) (e.g., Ferraro, 2004;Qiu et al, 2005). In the design of PNPR v2 we have focused on the exploitation of the improved technical characteristics of ATMS with respect to AMSU/MHS, with the analysis of the information carried by two new channels in the 183 GHz water vapor absorption band (at 183.31 ± 4.5 and 183.31 ± 1.8 GHz) (see Sect.…”