The open database of regional models of the International Service for the Geoid

This paper describes the development of a web application to facilitate the management and processing of geoid models in the ISG collection as well as of additional information available in the ISG website (mainly projects, services and publications). The ISG service pays significant attention to metadata and data interoperability from published geoid models. As a result, the possibility of creating a database with all necessary information for describing geoid models has been considered. PostgreSQL was chosen as the database for the implementation to take advantage of PostGIS geographic processing functions for developing a Database Management System for the resources available inside the ISG service catalogue (including geoid products, software, publications, etc.). The project's web development environment is Django, a web framework which is supported by the PostgreSQL database back-end and which makes it easier to integrate new applications or processing services into the website. A model solution for raster data integration using a PostGIS database back-end named Django-raster has also been investigated as part of the implementation, provided also that it is possible to take advantage of the vast Django community. The Django-raster model allows for the storage of datasets as tiles in the database, their exposure as a Tiled Map Services (TMS), and allows as well raster map algebra operations. TMS services will be utilized to share the geoid models and metadata included in the open access archive using a WebGIS, created with OpenLayers.