During the past two decades, the scope of geodesy extended from measuring the shape, rotation and gravitational field of the Earth towards providing reliable and accurate measurements of a highly dynamic and complex system Earth. This change of geodesy into a multidisciplinary science is based on the significant technological improvements of geodetic space techniques and the launch of various Earth observing satellites. The geodetic community recognized the need of incorporating the variety of sensor systems in space and on Earth into a common observing system and benefit from the strengths of each observation technique. Therefore, in 2007, the Global Geodetic Observing System (GGOS) was raised to a full component of the International Association of Geodesy (IAG). The aim of GGOS is to integrate the different geodetic observation techniques for a consistent monitoring of spatial and temporal changes of global surface dynamics in combination with an assessment of mass anomalies, transports and exchange processes. A fundamental role in this integration plays the global terrestrial reference frame.
As one of the key techniques of space geodesy, Satellite Laser Ranging (SLR) is the only technique capable to determine the origin (center of mass) and scale of the terrestrial reference frame (TRF) together with VLBI with very high accuracy. Moreover, SLR is a key technique for determining the long-wavelengths of the Earth's gravitational field. Using SLR observations, the TRF, the Earth orientation parameters (EOP) and the Earth's gravitational field can be estimated in one common adjustment which allows scientists to study parameter correlations and interactions. Since retro-reflectors are totally passive and can be installed very easily on satellites, most of today's geodetic Earth orbiters are equipped with SLR tracking technology. Therefore, also for precise orbit determination (POD), SLR plays a crucial role.
The presented paper gives an overview of present strategies to achieve the GGOS goals in future and outlines the importance of SLR for the geodetic community. In particular, the current SLR-related space and ground segment are evaluated w.r.t. their potential for GGOS and the accuracy of selected geodetic products. As a case study, SLR observations to satellite constellations are used to realize a consistent estimation of the Earth's shape, rotation and gravitational field. Furthermore, selected geophysical applications are presented which emphasize the importance of consistent geodetic measurements for a reliable interpretation of global change phenomena. Finally, the strategy of the ILRS to meet these manifold and challenging goals is discussed.
«
During the past two decades, the scope of geodesy extended from measuring the shape, rotation and gravitational field of the Earth towards providing reliable and accurate measurements of a highly dynamic and complex system Earth. This change of geodesy into a multidisciplinary science is based on the significant technological improvements of geodetic space techniques and the launch of various Earth observing satellites. The geodetic community recognized the need of incorporating the variety of s...
»