## 7 Results  
In this section, we discuss the results of the numerical analysis carried out on the selected images of Table 1.  
* the estimated Doppler Anomaly maps converted to the sea surface (line-of-sight component) velocity (point 6 left arrow in Figure 4);
* the wind direction obtained from the (Bayesian) CMOD and from the WRF-ARW model (point 3 in Figure 4);
* the wind speed relative to the CMOD model and to the WRF-ARW model (point 3 in Figure 4)
* the surface radial velocity due to the wind component, evaluated by the D-GMF as described in Section 4 for both winds estimated by WRF-ARW and refined by the CMOD-based Bayesian model (point 6 in Figure 4, middle and right products). It can be noticed that the estimated velocity ranges between \(\pm\) 100 cm/s, red and blue colors (redshift and blue shift) of the estimated sea surface velocity component indicate a motion toward and away from the radar antenna, respectively. Figure 6 refers to the acquisition of 17 November 2004; in this case, the amplitude image (Figure 6A) shows an evident pattern in the north of the Ischia Island area. This pattern is observed also in the image corresponding to the surface currents (Figure 6B) with a redshift located in the same position. The image in Figure 6B also shows another pattern with a component of the surface current toward the sensor in the south-most region of the swath: no significant variation, however, is observed in the same area in Figure 6A. Both patterns can be explained, although partially, by looking at the wind data of the WRF-ARW model wind: the arrows' direction (Figure 6D) indicates in fact the presence of a wind blowing towards the sensor (upwind condition). However, the north pattern has a sharper transition than the southern one in terms of wind direction. In the most westerly part of both Figure 6C,D, a wind blowing almost parallel to the azimuth direction, i.e., in the direction orthogonal in the LOS, can be noticed: a feature that seems to be correctly mapped in the DCA measurement on the left part of Figure 6B. Such a transition is even more emphasized in the refined wind measurements following the MAP based on CMOD estimator for the wind described in Section 3 (see Figure 6C,E,F for the intensities). The surface radial velocity obtained via the Doppler model described in Section 4 shows a rather good match with the Doppler measurement achieved by processing the complex SAR data (Figure 6B) for both the WRF-ARW (Figure 6H) and the CMOD wind (Figure 6G). However, the CMOD derived surface velocity (Figure 6G) shows a higher spatial match with Figure 6B when compared to the WRF-ARW derived surface velocity in Figure 6H. Finally, in Figure 6G it is noticeable only a partial mismatch on the northern pattern, likely due to a bias of the WRF-ARW wind source on the estimation of the wind direction in CMOD MAP based estimator. In Figure 7 are presented the results relative to the acquisition on 22 December 2004, also in this case, in the amplitude image (Figure 7A), there is a pattern in the northern part of Ischia Island (less evident than the case of Figure 6A), which is also present in the surface radial velocity of Figure 7B. In the south-east area of the DCA map (Figure 7B) a redshift is again observed; it represents a surface current that moves toward the sensor. Wind directions of Figure 7C,D can explain such a behavior because they show, also in this case, the presence of an upwind: the wind magnitude (see Figure 7E,F) confirms this evidence too. Finally, Figure 7G,H highlight that in the upwind condition the radial velocity obtained via the D-GMF described in Section 4 tends to overestimate the radial velocity, i.e., shows a redshift also in areas of with low wind magnitude. This behavior is in agreement with the plots in Figure 3, which show that the in the upwind condition the D-GMF provides radial velocities different from zero even in the case of very low wind magnitude (Figure 3 left), whereas with wind directions orthogonal to the LOS (Figure 3 right), it does not provide contributions.