News and Activities
GGOS IberAtlantic (GGOS IA) functions as a regional node of GGOS, focusing on geodetic activities across the Iberian Peninsula and the Atlantic region. GGOS IA fosters collaboration among geodetic institutions while promoting scientific research and technological development tailored to the region’s unique geophysical characteristics.
UN-GGCE “Listening World Tour” – IAG
Other, 📅 Event UpdateVirtual Meeting between IAG and UN-GGCE
The United Nations Global Geodetic Center of Excellence UN-GGCE will be hosting two listening sessions to maximize the opportunity for participation from IAG members all around the world. Both sessions will have the same agenda, so please choose which time suits you.
Concept Note
The vision of the United Nations Global Geodetic Centre of Excellence (UN-GGCE) is one where all countries have strong political support for geodesy which enables them to – together – accelerate the achievements of the Sustainable Development Goals and derive social, environmental and economic benefits. Our objective is to work with Member States and geodetic organizations to strengthen our collective impact to:
The UN-GGCE recognizes the important role the International Association of Geodesy (IAG) plays in the geodetic community. In particular, the enormous in-kind contribution IAG representatives and their respective Member States / organizations provide throughout the supply chain of infrastructure construction and operation, data collection, analysis, product development and data sharing. The UN- GGCE’s role is not to duplicate any of the work being done by the IAG. Instead, one of the UN-GGCE roles is to support IAG to continue to deliver on its mission and objectives.
The staff in the UN-GGCE would like to meet with IAG representatives, listen to you and better understand how we can assist you.
Participation
The “Listening World Tour” virtual meeting will be open to members of IAG.
More information
Author: UN-GGCE
Editor: Martin Sehnal
Report of the GGOS Days 2023
GGOS, 📅 Event UpdateGGOS convenes its various components annually to report on achievements and formulate activities for the future. On this occasion, the Instituto Geográfico Nacional of Spain hosted the GGOS Days in Alcalá de Henares from 20th to 22nd September 2023. The meeting was hybrid, enabling remote participation, and had 192 attendees, 40 of whom were present in person.
The conference agenda included 10 sessions, beginning with a presentation by Spanish and Portuguese colleagues outlining the current status and future plans for space geodesy in their respective countries. Noteworthy was the informed decision to install the GGOS Affiliate Iberatlantic. The keynote speaker session featured three pertinent contributions on interesting geodetic subjects:
As GGOS Affiliate Japan celebrates its 10th anniversary, its major accomplishment is deploying the latest technology in Japanese fundamental geodetic observatories. The GGOS Affiliate D-A-CH focuses on creating methodologies that combine and integrate all geodetic techniques consistently. This goal enhances the precision and dependability of geodetic outcomes.
The GGOS External Activities presentations highlighted recent accomplishments of the UN Sub-Committee on Geodesy, perspectives for South America’s involvement in GGOS, and the collaborative efforts of the IAG’s Communication and Outreach Branch and the Coordinating Office of GGOS to enhance the visibility of the IAG and Geodesy. Initiatives promoting the FAIR (Findable, Accessible, Interoperable, and Reusable) data principles within the IAG were extensively discussed. Specifically, the utilization of DOIs for geodetic data and products and the implementation of the GGOS portal as a convenient one-stop-shop for all geodetic products from IAG and its various components were emphasized.
In the GGOS Bureau of Networks and Observations (BNO) session, the IAG Services presented recent achievements and new challenges objectively. This session provided a comprehensive overview of current Service activities. Additionally, the Committee PLATO (Performance Simulations and Architectural Trade-Offs) presented an update on recent simulations aimed at enhancing the geometric configuration of space geodetic reference stations. The Committee on Satellite Missions provided an assessment of the technical features and application areas of the newly sanctioned gravity mission MAGIC (Mass change and geoscience international constellation). The Committee on Data and Information Systems reported on the progress in deploying GeodesyML (Geodesy Markup Language), a tool that simplifies the manipulation of geodetic data and metadata, including those related to equipment, site logs, measurement, adjustment, quality, monuments, reference frames, and data lineage. The GGOS/IERS joint working group on Site Survey and Colocation shared information about the local ties that have been measured at 20 stations since 2020. The number of intra-technique vectors increased from 212 to 253.
At the GGOS Bureau of Products and Standards (BPS) session, after an overview presentation showing objectives, structure and activities of this Bureau, interesting discussions about the computation of a new reference level ellipsoid and the implementation of a catalogue with Essential Geodetic Variables were conducted. This session closed with a review of the Committee Contributions to Earth System Modelling.
Regarding the GGOS Focus Areas (FA), the FA Unified Height System presented a final report about the integration of its activities into the IAG Commission 2 (Gravity Field) and the IGFS (International Gravity Field Service). This FA was dissolved at the General Assembly of the IUGG (International Union of Geodesy and Geophysics) in Berlin in July 2023, having achieved its objectives. The FA on Geohazards presented a status report focused on the advancement of GNSS-based Tsunami Early Warning Systems (GTEWS) and the establishment of a GTEWS capability for the South Pacific’s Oceania region. The FA on Geodetic Space Weather Research summarised accomplishments in four research areas, namely: the coupling processes among the magnetosphere, thermosphere and ionosphere; modelling of the electron density; development of thermosphere models; and comprehension of space weather events and their supervising through satellite missions. The recently established FA on Artificial Intelligence for Geodesy (AI4G) reported on strategies for the development and evaluation of improved geodetic products based on AI and machine learning. Specific presentations on AI for GNSS remote sensing, gravity field and mass change, prediction of Earth orientation parameters, and geodetic deformation monitoring were given. In addition, the topics and objectives of two new potential focus areas on the combination of tropospheric parameters and the integrated analysis of GNSS and InSAR data were discussed.
The remaining sessions were devoted to redefining the memberships of the GGOS management structure, following the customary practice within the IAG every four years.
The GGOS Days 2023 featured a technical visit to the Yebes Observatory, a notable scientific facility focused on astronomical and geodetic research and observation, and a key contributor to the IAG and its Services. The Yebes Observatory staff conducted a comprehensive tour of the recently installed equipment and facilities for the conference attendees over the course of an entire afternoon. The exceptional professionalism and friendly welcome of our colleagues at Yebes Observatory created an unforgettable visit.
Further information regarding the GGOS Days 2023 conference, presentations, and outputs can be accessed at: https://ggos.org/event/ggos-days-2023/
We extend our sincerest gratitude to the Instituto Geográfico Nacional and the Yebes Observatory staff for their unwavering commitment in organizing this successful meeting. Moreover, we are thankful to the numerous speakers who, through their dedication and hard work, make GGOS possible. We would also like to thank all participants for their interest and active contribution to the discussion. Finally, we express our special gratitude to the IAG Office for providing travel awards to some participants, enabling them to attend this event.
Laura Sánchez, GGOS President, Deutsches Geodätisches Forschungsinstitut der Technischen Universität München (DGFI-TUM), Germany
José Antonio López Fernández, Chair of the Local Organizing Committee, Instituto Geográfico Nacional, Spain
Martin Sehnal, Director of the GGOS Coordinating Office, Federal Office of Metrology and Surveying, Austria
Symposium on Gravity, Geoid and Height Systems – GGHS2024
Com2, GGOS, IGFS, 📅 Event UpdateThe GGHS2024 “Gravity, Geoid and Height Systems 2024” Symposium will be held in Thessaloniki, Greece, from 4 to 6 September 2024. It focuses on methods for observing, estimating and interpreting the Earth’s gravity field and the essential role of gravity field modelling in measuring, understanding and predicting changes in the Earth system.
GGHS2024 continues the long history of IAG gravity field related symposia, initially hosted by the IAG Commission 2 (Gravity Field):
those organized by the International Gravity Field Service (IGFS):
And more recently the joint IAG Commission 2 and IGFS Symposia:
On this occasion, GGHS2024 is co-organized by the IAG’s Global Geodetic Observing System (GGOS).
SUBJECTS ‐ THEMES
During the last decade, geodesy in general and gravity field modelling in particular, have experienced a notable growth in their recognition and end-product use by many scientific disciplines.
This was mainly due to the advent of the dedicated legacy satellite gravity missions of CHAMP, GRACE and GOCE, which have brought new insights to both the static and time-variable representations of the Earth’s gravity field. GRACE Follow-On has seamlessly integrated with the 15-year GRACE data record and has become indispensable for a wide variety of geophysical process and climate studies. New mission concepts, like NGGM, new accelerometers for satellite gradiometry, cold atom gravimetry, and new and enhanced processing technologies, shall substantially improve this knowledge with further increased spatial and temporal resolution. Moreover, the continuous availability of altimeters on-board satellites and the improvements in the representation of the marine geoid have provided higher accuracies to shorter spatial scales of the marine geoid and gravity field, ocean topography and circulation as well as the structure of the oceanic crust.
At the time came advancements in traditional terrestrial, airborne, UAV and shipborne gravity instrumentation, which offer considerable improvements in gravity networks and the monitoring of gravity variations. Absolute quantum gravimeters have emerged and are gradually replacing free-fall corner cube ones, concepts on quantum sensors are investigated as future payloads for gravity dedicated space missions, while results from gravimeters based on MEMS and airborne sensors on UAVs are emerging.
Another a major breakthrough for the gravity and geoid community has been the definition of the International Height Reference System (IHRS) and the practical realization of the International Height Reference Frame (IHRF). Concepts for geoid and potential determination have been developed and tested aiming at providing a roadmap for the definition and realization of physical heights into a worldwide frame. The latter can lead to the linkage of local vertical datums to a global one, which is fundamental for monitoring sea level variations, as well as engineering and hydrological and cryosphere studies.
The collocated use of the new datasets and models offered by gravity-field related research improves the knowledge of the Earth system, its sub-systems, coupling processes among them, which are important indicators for climate change. They provide the building blocks for innovative investigations of the solid Earth giving new details of crust and mantle and their variation in time.
Contributions on methods for observing, modelling and interpreting the Earth’s gravity field, the determination of the geoid, the establishment of physical height systems, and the essential role of gravity field modelling in measuring, understanding and predicting changes in the Earth system are welcomed for presentation at the GGHS2024 Symposium.
GGHS2024 SESSIONS
Session 1: Reference systems and frames in Physical Geodesy
Session 2: Novel technologies in terrestrial, airborne and satellite gravity field determination
Session 3: Static and time-variable global gravity field modelling
Session 4: Regional gravity field modelling and geophysical interpretation
Session 5: Gravity for climate, atmosphere, ocean and natural hazard research
Section 6: Data management, dissemination of results and networking of stakeholders
Author: George S. Vergos, Laura Sánchez, Srinivas Bettadpur, Riccardo Barzaghi
Editor: Martin Sehnal