## 3 Comparative Analyses Results
### CMORPH Products
Moreover, CMORPH-RT applied only a forward propagation at the time of the precipitation fields once estimated by PMW satellites without modifying the intensity or the shape [47]. The strong underestimation experienced by CMORPH-RT can be attributed to the CMORPH-RT simple-shot. The June case was convective and thus contained a rainfall regime with a rapidly changing structure, which may have been missed by CMORPH-RT, as it had to 'wait' for the next PMW sensor estimation. Despite finding negative biases over the areas of interest with both products, the spatial representation of both cases by CMORPH were closer to the RADOME observation than CMORPH-RT. CMORPH represented both case studies with a smoother appearance due to its morphing algorithm (see Section 2.1.3). Figure 14: As in Figure 4, but for the CMORPH product. The rain accumulations estimated for both April and June case studies are presented in Figure 15a,b for GSMaP-Now, Figure 16a,b for GSMaP-Now-GC, Figure 17a,b for GSMaP-NRT, and Figure 18a,b for GSMaP-NRT-GC (the details of GSMaP family products are presented in Table 1 and Section Microwave Sensor-Based and Blended Products). The differences between GSMaP-Now and GSMaP-Now-GC (Figures 15a and 16a for April and Figures 15b and 16b for June) were mainly limited to the intensity of the events regionally. A similar statement can be made about the differences noted between GSMaP-NRT and GSMaP-NRT-GC for both case studies (Figures 17a and 18a for April and Figures 17b and 18b for June). The distribution of the absolute bias of GSMaP-Now products and GSMaP-NRT products is represented in Figures 15c,d and 16c,d; and 17c,d and 18c,d, respectively. For GSMaP-Now products during the April case (Figures 15a,c and 16a,c), the most intense precipitation pattern was located over the west border of the WMC area. Another area of high-intensity precipitation pattern was located in the north of the Alps, whereas moderate-intensity precipitation amounts (between 15 to 30 mm) were observed by RADOME. Both these high-intensity precipitation patterns have a westerly shift (for the WMC area) and a northerly shift (for the Alps) compared to the RADOME observations (Figure 2a). For every area, the distance from both GSMaP-Now products' maximums to RADOME maximums were identical, regardless of the effect of the gauge adjustment (Table 2). Furthermore, it is important to note that the minimal distance separating both maximums was approx. 80 km, marking the difficulty of both GSMaP-Now products to correctly identify the location of each maximum. By looking at the distribution of absolute biases (Figures 15c and 16c), we can see that a large area of underestimation extended from the south of the Alps westward to the eastern part of the WMC area. Figure 15: As in Figure 4, but for rain accumulations estimated by the GSMaP-Now product. Figure 16: As in Figure 4, but for the GSMaP-Now GC product. Figure 17: As in Figure 4, but for the GSMaP-NRT product. We can see the first overestimation pattern was identified in the north of the Alps confirming a northern shift in the high-intensity precipitation amounts observed by RADOME over the South Alps areas. A second overestimation signal was present in the west of the WMC area, confirming a western shift of the high precipitation amounts observed over the WMC area. This leaves a general underestimation trend for both GSMaP-Now products over the study areas (ranging from \(-3.69\) mm over the WMC to \(-21.05\) mm over SAL on average for GSMaP-Now and from \(-5.54\) mm over JUR to \(-24.44\) mm over SAL on average for GSMaP-Now-GC). As for the June event (Figures 15b,d and 16b,d), GSMaP-Now and GSMaP-Now-GC reproduces the high-intensity rainfall patterns close to the borders with Belgium and Germany (Figures 15b and 16b). We can observe low-intensity precipitation amounts and low maximums for both products over the NMC area (82.83 mm for GSMaP-Now and 82.43 mm for GSMaP-Now-GC against 136.7 mm for RADOME; Table 2).