## 6 Quantitative Method to Identify the Potential Technologies to Cover the Future Copernicus Gaps
In order to evaluate the robustness of the methodology implemented, a sensitivity analysis at 25% has been performed to estimate the impact of the weights over the ranking of the technologies. Figure 3 shows the same trend in the rank of the technologies by varying randomly 100 times all weights at the same time for each use case prioritized. In this model, the priority level of the measurements and the number of measurements that can measure the sensors are the critical parameters to rank the technologies. When the priority use case is Marine for Weather Forecast, the key technologies in ranked order are GNSS-R, X- band SAR imager, and Radar Altimeter with SAR processing (Table 12, columns 1 and 2). The sensitivity analysis is summarized in Figure 3a. The simultaneously random weights defined a clear trend in each technology. Columns 1 and 3 of the Table 12 shows the relevant technologies when selecting the Sea Ice Monitoring use case as the priority. They are X-band SAR, GNSS-R, X-, K-, Ka-, W-band MWIm, and Radar Altimeter (SAR). Figure 3b presents a similar tendency in the results when the weights are varying randomly. The valuable technologies for the Agriculture- Hydric stress use case in ranked order are Multispectral sensors, GNSS-R, Hyperspectral, and L-band MW; the same distribution has been found in the sensitivity analysis (Figure 3c). Figure 3d shows the sensitivity analysis of the technology rank when the Fishing Pressure use case is the priority. The most important technology also is the Multispectral sensor. In general, the prioritized list of the main technologies to ensure that the gaps are covered taking into account the priority level of different use cases in the time frame 2020-2030 are GNSS-R, imaging X-band SAR, with 1 km of spatial resolution, and Multispectral sensor. GNSS-R provides support to marine and land services of Copernicus and can collaborate with other technologies to improve the measurements. SAR can provide several data from the ocean and can collaborate with the land data. The best ranked optical payload to support multiple services of Copernicus program is a Multispectral sensor with bands in the VIS (442.5, 485, 490, 510, 560, 640, 660, 665 nm), NIR (1610 nm), MWIR (3.7, and 4.05 um) and TIR (8.55, 11, and 12 um). \begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline  & & \multicolumn{3}{c}{**Ranking Results [\%]**} \\ \cline{2-5}
**Instrument/Technology** & **Marine for Weather Forecast** & **Sea Ice Monitoring** & **Agriculture and Forestry: Hydric Stress** & **Fishing Pressure** \\ \hline
**Multispectral Radiometer** & 21.6 & 23.1 & 30.1 & 31.2 \\ \hline
**Hyperspectral Radiometer** & 11.2 & 10.7 & 19.9 & 11.8 \\ \hline
**Hyperspectral. Sounder (IR)** & 10.6 & 8.5 & 6.1 & 11.4 \\ \hline
**L-Microwave Radiometer** & 8.5 & 10.6 & 19.4 & 8.1 \\ \hline
**Ka, K, W-Microwave Radiometer** & 19.3 & 21.6 & 11.2 & 10.4 \\ \hline
**GNSS-R** & 39.4 & 29.6 & 24.8 & 25.3 \\ \hline
**X-, Ka, K, W-Microwave Radiometer** & 21.2 & 23.7 & 12.1 & 14.6 \\ \hline
**Ka-, U-, D-Microwave Sounder** & 5.9 & 2.37 & 3.4 & 5.1 \\ \hline
**Automatic Identification System (AIS)** & 3.1 & 5.0 & 3.6 & 8.1 \\ \hline
**Radar Scatterometer** & 11.9 & 12.7 & 6.8 & 6.8 \\ \hline
**Lidar** & 1.04 & 2.5 & 1.2 & 1.8 \\ \hline
**Synthetic Aperture Radar (SAR) Altimeter** & 27.9 & 21.4 & 12.7 & 16.3 \\ \hline
**X-SAR Imager** & 30.8 & 32.5 & 18.23 & 23.56 \\ \hline \hline \end{tabular}
\end{table} 
Table 12: Ranking results for each technology for each use case. Figure 3: Sensitivity analysis at 25% for different use cases priorities. (a) Marine for Weather Forecast; (b) Sea Ice Monitoring; (c) Fishing Pressure; (d) Agriculture and Forestry: Hydric Stress.