The Global Geodetic Observing System (GGOS) is an important component of the International Association of Geodesy.
GGOS aims to integrate all geodetic observations in order to generate a consistent high quality set of geodetic parameters for monitoring the phenomena and processes within the “System Earth”.
Integration implies the inclusion of all relevant information for parameter estimation, implying the combination of geometric and gravimetric data, and the common estimation of all the necessary parameters representing the solid Earth,
the hydrosphere (including oceans, ice-caps, continental water), and the atmosphere. This paper will describe
the background to the establishment of GGOS, discuss the important role to be played by GPS/GNSS infrastructure
in realising the GGOS mission and provide an update status of GNSS CORS in Thailand