The European Space Agency (ESA) with the launch of the GOCE satellite in 2009 made it possible to study the Earth's gravitational field and estimate the geoid with unprecedented accuracy and resolution on a global scale. In the framework of the GOCE mission a group of experts from Politecnico di Milano, led by Professor Fernando Sansò, is also involved in order to collect, process and distribute data. Access to GOCE data, through common procedures and standard, can bring significant improvement in many fields of Earth sciences: for this reason it was decided to distribute the data using standard web services as specified by OGC (Open Geospatial Consortium). In this work first results of the development of a WPS (Web Processing Service) for spatio-temporal exploration and exploitation of GOCE and GEMMA (GOCE Exploitation for Moho Modeling and Applications) data is presented. The download query can be made for both global data and local data; in the latter case data can be dynamically interpolated from the WPS on the area and at the resolution defined by the user, or evaluated in correspondence of a set of sparse points provided by user. The GOCE service is implemented with free and open source software, GRASS GIS and pyWPS for WPS service and OpenLayers for the web interface. Furthermore the development of WMS and WCS services is on going; a WFS service, built using MapServer and to be used for the data distribution, will be added soon to improve the ASCII Grid and GeoTIFF formats that are currently available and also a new interpolation algorit based on spherical harmonics will be added too. The service is continuously updated from the point of view of the available data, the calculation procedures and data distribution.