# A GeoNode-Based Platform for an Effective Exploitation of Advanced DInSAR Measurements
## 6 Discussion  
SAR technology has already proven to be a key solution for monitoring wide areas of the Earth's surface. In particular, the DInSAR techniques have demonstrated their capabilities to generate deformation maps and time-series suitable to detect, map and analyse the on-going surface displacement phenomena with centimetre to millimetre accuracy. Despite the huge range of applications developed in recent years, the operational use of DInSAR results obtained from the new generation satellite systems, such as the Sentinel-1 constellation, is hindered by the large amount of available measurements (note that the Sentinel-1 constellation already collects more than 10 TByte of data per day). Accordingly it is evident the need for developing advanced methodologies and techniques to handle such large DInSAR datasets of deformation maps and time-series. This work concerns the implementation of a SDI for managing, visualizing, analysing, and integrating with other data sources, large volumes of DInSAR results.  
In particular, we focused on the GeoNode platform infrastructure which represents an excellent framework to implement a SDI and to extend the SDI functionalities in order to adapt them to our DInSAR-related requirements. More specifically, we underline that GeoNode:  
1. [label=()]
2. permits development of geospatial services within a fully free and open source framework;
3. is an environment originally developed to manage geographic contents that easily allows the extension of its functionalities.  
Moreover, as future perspectives, the use of a completely open source architecture like GeoNode gives us the possibility to distribute the developed codes under a GNU General Public Licence (GPL) [119]. In addition, a further improvement could be represented by the development of tools for animations relevant to the deformation time-series of a single pixel or for those of an area of interest.  
We further remark that, since one of the most appreciated characteristics of GeoNode is the possibility to access to the data by using open standards endorsed by OGC (i.e., WMS and WFS for accessing maps and data and CSW as metadata catalogue), the proposed approach may contribute in paving the path to build a straightforward environment to find and share DInSAR data in an interoperable way and throughout multiple initiatives and projects, thus encouraging their reuse. Indeed, the available data can be offered through standard webservices, which are fundamental  
Figure 19: Example of joint analysis of different data sources: overlap of the DInSAR mean deformation velocity (see Figure 10) and the Italian municipalities seismic classification [118] maps relevant to the zone affected by the 2016-2017 seismic crisis in central Italy.  
components of SDIs. We further remark that in the SDIs a particular attention is requested by metadata, an essential enabling factor for geospatial assets because discovery, retrieval, actual usage and re-use of data are tightly bound to the readability and quality of these descriptions. Like in many other use-cases, where geospatial metadata are often encoded in formats that are not aimed at easing searching and retrieval, also for the DInSAR data they are particularly difficult to be read and interpret, making more puzzling and boring the task of users who must fill metadata resources. To this purpose an open-source editing tool has been developed [120], which can be easily included in the overall architecture depicted in Figure 4 and in the flow chart of Figure 6, so that numeric metadata values in the DInSAR header can be made clear to generic users' interpretation and users' searching can be made more effective. These tasks are certainly worthy of future analysis.