[S-GD02] Geodesy and Global Geodetic Observing System

[SGD02-01] The Global Geodetic Observing System (GGOS) - Recent focuses and activities in Japan -

*Basara Miyahara¹, Toshimichi Otsubo², Yusuke Yokota³, Shinobu Kurihara¹, Martin Sehnal⁴, Laura Sánchez⁵ (1.GSI of Japan, 2.Hitotsubashi University, 3.The University of Tokyo, 4.BEV Austrian Federal Office of Metrology and Surveying, 5.Deutsches Geodätisches Forschungsinstitut Technical University of Munich)

Keywords:GGOS, IAG, GGOS Japan, Co-location, Space geodetic technique

The Global Geodetic Observing System (GGOS) is a collaborative contribution of the global Geodesy community to the observation and monitoring of the Earth System. Geodesy is the science of determining the shape of the Earth, its gravity field, and its rotation as functions of time. Essential to reaching this goal are stable and consistent geodetic reference frames, which provide the fundamental layer for the determination of time-dependent coordinates of points or objects, and for describing the motion of the Earth in space. With modern instrumentation and analytical techniques, Geodesy is capable of detecting time variations ranging from large and secular scales to very small and transient deformations – all with increasing spatial and temporal resolution, high accuracy, and decreasing latency. The geodetic observational and analysis infrastructures as well as the high-quality geodetic products provide the foundation upon which advances in Earth and planetary system sciences and applications are built. In this way, GGOS endeavors to facilitate and enable production and sharing of the Earth observations needed to monitor, map, and understand changes in the Earth’s shape, rotation, and mass distribution. GGOS also advocates the global geodetic frame of reference as the fundamental backbone for measuring and consistently interpreting global change processes as well as the essential geospatial infrastructure to ensure a homogeneous and sustainable development worldwide. GGOS closely works with its parent organization, the International Association of Geodesy (IAG), to keep these fundamental geodetic contributions sustainable. The IAG Services provide the infrastructure and products on which all contributions of GGOS are based, and the IAG Commissions and IAG Inter-Commission Committees provide expertise and support to address key scientific issues within GGOS. Additionally, GGOS supports the IAG by strengthening external and interdisciplinary relations and contributions to the broader geospatial information community, including relevant United Nations groups, in particular, the United Nations Committee of Experts on Global Geospatial Information Management (UN-GGIM), its Subcommittee on Geodesy, and the new UN Global Geodetic Centre of Excellence (scheduled to commence operations in early 2022). The main contribution of GGOS in this regard is to support actions and initiatives to communicate the value of Geodesy to society as well as to help to understand and solve complex issues facing the global geodesy community. Towards this objective, GGOS is developing a comprehensive Geodesy portal (https://ggos.org/) including detailed descriptions of geodetic observations (https://ggos.org/obs/) and products (https://ggos.org/products/), and various outreach tools such as short videos to explain the roles and importance of Geodesy to non-geodesists. Active participation from regions and countries is also a key enabler to strengthening global geodetic collaboration and GGOS Affiliate is a GGOS component to tackle this challenge. The first GGOS Affiliate, GGOS Japan was established in 2013 and have been working to strengthen collaboration between GGOS and geodetic organizations/institutions in Japan. The second GGOS Affiliate, GGOS D-A-CH was also established in 2020 and is seeking opportunities to enhance collaboration with GGOS Japan. GGOS Japan is developing a video of VLBI-GNSS local tie survey at Ishioka Geodetic Station as an outreach tool for roles and importance of co-location to geodetic reference frame realization. In addition, GGOS Japan is discussing the appropriate mechanism to assign DOIs for geodetic dataset in Japan and collaborating with Geodetic Society of Japan to identify and realize the most probable and proper way in Japan. Through the activities, GGOS Japan is contributing to GGOS by strengthening collaboration among organizations/institutions in Japan and supporting their participation to GGOS.