## 4 Results
### Evaluation of the Results  
To compare the results, we firstly estimated the difference in the proportion of vegetation cover produced from the two different models. Figure 9a shows the difference the OpenStreetMap (Equation (3) and image statistics (Equation (5)) for the RVI, while Figure 9b shows the difference between the proportion of vegetation cover using the NDVI (Equations (4) and (6)). Higher differences between the two models are shown with a red colour while lower differences are estimated with a blue colour. However, examining the findings of Figure 9a,b, it is still difficult to compare the two outcomes. Differences in the pattern are apparent, indicating that the selection of the type of sensor (i.e., Sentinel-1, radar and Sentinel-2, optical sensors) influences the outcome. Figure 8: The proportion of vegetation cover based on the RVI using Equation (3) (**a**) and Equation (5) (**b**), and the NDVI based on Equation (4) (**c**) and Equation (6) (**d**). Figure 9: (**a**) Difference of the proportion of vegetation cover as estimated from the Radar Vegetaton Index (RVI) based on Equations (3) and (5) and (**b**) Difference of the proportion of vegetation cover as estimated from the Normalized Difference Vegetation Index (NDVI) based on Equations (4) and (6). Higher difference values are indicated with red colour, while lower values with blue colour. We further estimated the differences between the findings of Figure 9a,b. The results of this analysis are shown in Figure 10b. As shown in this Figure, differences in the estimation of the proportion of vegetation can vary significantly and over 40% using the optical (NDVI) and radar (RVI) indices. However, a closer look at these findings shows that the differences between these two types of satellite sources are minimal (\(<10\%\)) over vegetated areas (Figure 10c). This finding suggests that the estimation of the proportion of vegetation obtained by the Sentinel-1 and -2 sensors does not differ significantly over vegetated areas. This is also supported from the findings of Figure 6, whereas a similar pattern can be extracted for optical and radar products over vegetated areas (but not for other types of targets). Indeed, the use of the factor in Equation (2) can be adjusted for other types of targets. In addition, the scene classification product of the Sentinel-2 image of 13 May 2020 is shown in Figure 10d. Vegetated areas are shown in this Figure with a green colour, which recaps the findings of the results from Figure 10c, however with a lower resolution. The results of Figure 10c were compared with a high-resolution optical satellite image available at the ArcGIS environment, at the northern part of the archaeological site of \"Nea Paphos\" (Figure 11a). Figure 11b shows a closer look at the findings of Figure 10c in this area, indicating that the difference is relatively low (blue colour in Figure 11b) over the vegetated areas. The results from the proportion of  
Figure 10: **(a)** High-resolution satellite image over the case study area, **(b)** difference between the results of Figure 9a,b, **(c)** areas with minimum differences between the optical and the radar sensor indicated with blue colour over agricultural areas and **(d)** classification scene of Sentinel-2 images, whereas as vegetated areas are shown with green colour. vegetation based on the optical Sentinel-2 sensor and using the NDVI and the OpenStreetMap inputs are shown in Figure 11c, while a high proportion of vegetation is highlighted with a yellow colour. While a direct comparison between the vegetation proportion from the RVI and the NDVI is not feasible, in an attempt to integrate the findings, we multiplied the RVI and the NDVI results (see Figure 8a-c), whereas high values will be expected in pixels with a high RVI and NDVI proportion of vegetation estimation, indicating vegetation presence. The results are shown in Figure 12. Figure 12a shows the multiplied RVI \(\times\) NDVI results, whereas higher values indicated with a green colour highlight vegetated areas.