Supporting Earth Sciences: The Global Geodetic Observing System (GGOS) Ruth Neilan

1. GG S Supporting Earth Sciences: The Global Geodetic Observing System (GGOS) Ruth Neilan Director, International GNSS Service Central Bureau NASA/Jet Propulsion Laboratory (JPL)/California Institute of Technology http://www.ggos.org http://igs.org US-China Workshop Boulder, Colorado November 14, 2008

2. Global Geodetic Observing System (GGOS) IGS Update Data and Products Challenges Information and Data - ICSU, IUGG, GEOSS GNSS System Advances International Committee on GNSS Summary and Outlook Overview

3. Helplessness in the face of natural disasters demonstrates that our knowledge of the Earth’s complex system is rather limited. Motivation

4. Motivation: Monitoring the Earth System

5. Helplessness in the face of natural disasters demonstrates that our knowledge of the Earth’s complex system is rather limited. Deeper insight into the processes and interactions within this system is one of the most urgent challenges for our society. To monitor changes in the Earth system and the processes causing natural disasters a Global Earth Observing System (GEOSS) is being established. GGOS = geodesy’s contribution to GEOSS; GGOS as metrological basis for all monitoring: provides the global reference frame. Space geodetic techniques (VLBI, SLR/LLR, GNSS, DORIS), altimetry, InSAR, gravity missions, in-situ measurements, etc. allow the monitoring of the Earth system with an unprecedented accuracy (10-9) Motivation

6. GGOS: Monitoring and Modeling the Earth‘s System Terrestrial reference frame: high accuracy and long-term stability Measuring Information about Earth System Geometry Station Position/Motion, Sea Level Change, Deformation Space Geodetic Techniques VLBI SLR/LLR GNSS DORIS Altimetry InSAR Gravity Satel. Terrestrial Techniques Levelling Abs./Rel. Gravimetry Tide Gauges Air-/Shipborne Earth System Sun/Moon (Planets) Atmosphere Ocean Hydrosphere Cryosphere Core Mantle Crust I N T E R A C T I O N S C OM B I N A T I O N Earth Rotation Precession/Nutation, Polar Motion, UT1, LOD Gravity Geocenter Gravity field, Temporal variations Influence / Modelling Observation Modelling

7. IERS: Intern’l Earth Rotation and Reference Systems Service IGS: International GNSS Service IVS: International VLBI Service ILRS: International Laser Ranging Service IDS: International DORIS Service IGFS: International Gravity Field Service BGI: Bureau Gravimetrique International IGeS: International Geoid Service ICET: International Center for Earth Tides ICGEM: International Center for Global Earth Models PSMSL: Permanent Service for Mean Sea Level IAS: International Altimetry Service (in preparation) BIPM: Bureau International des Poids et Mesures IBS: IAG Bibliographic Service IAG Services: Backbone of GGOS Geometry Gravimetry Ocean Std

8. Space Geodetic Techniques DORIS GLONASS GPS GALILEO COMPASS VLBI SLR/LLR InSAR Altimetry

9. GGOS: the Ground-Based Component GPS/GLONASS VLBI Sup.Grav. GPS SLR/LLR DORIS Abs.Grav.

10. GGOS: the Satellite Mission Component CHAMP JASON-1 COSMIC TanDEM-X GRACE SWARM TerraSAR-X GOCE

11. International GNSS Service Formerly theInternational GPS Service GNSS: Global Navigation Satellite System The IGS is a voluntary federation of more than 200 worldwide agencies in more than 90 countries that pool resources and permanent GPS station data to generate precise GPS products. Over 350 permanent tracking stations operated by more than 100 worldwide agencies comprise the IGS network. Currently the IGS supports two GNSS: GPS and the Russian GLONASS. GPS Applications in IGS Projects & Working Groups IGS Reference Frame Supporting AREF - African Reference Frames Precise Time & Frequency Transfer GLONASS Pilot Service Project, now routine within IGS processes Low Earth Orbiters Project Ionosphere WG Atmosphere WG Sea Level - TIGA Project Real-Time Project Data Center WG GNSS WG IGS products are formed by combining independent results from each of several Analysis Centers. Improvements in signals and computations have brought the centers’ consistency in the Final GPS satellite orbit calculation to ~ 2cm http://igscb.jpl.nasa.gov NASA funds the coordinating center the IGS Central Bureau Graph courtesy Analysis Coordinator G. Gendt, GFZ Potsdam

12. Global Plate Motion

13. Gravity Field, Mass Transport Ilk et al. (2005) Mass Transport and Mass Distribution in the Earth System, 2nd Edition, SPP1257 DFG

14. Ensure the consistency and improve the accuracy of the resulting geodetic products Complementary use of the individual techniques to strengthen the solutions Benefits from observing instruments co-located at the same site/satellite Distinguish genuine geodetic/geo-physical signals from technique-specific systematic biases Crucial to achieve separation between different components and processes in the Earth System (e.g. mass transport) Combination / Integration

15. Data and data policy, national policies and global science International Council for Science, Strategic Committee on Information and Data to facilitate a new, coordinated global approach to scientific data and information that ensures equitable access to quality data and information for research, education and informed decision-making International Union of Geodesy and Geophysics establishing Inter-Union Committee on Data and Information GEO System of Systems - GEOSS Approach to data sharing principles http://www.earthobservations.org/geoss_dsp.shtml GNSS Evolution GPS modernization - new signals, GLONASS improvements Smooth transition, calibration, validation for continued long-term, quality observations Incorporating, integrating New GNSSs: China’s COMPAS, EU GALILEO - interoperabilty? Interchangeability Regional systems - Japan’s QZSS and India’s GAGAN - GPS-like signals Challenges

16. International Committee on GNSS (ICG) Committee on Peaceful Uses of Outer Space (COPUOS) - United Nations Office of Outer Space Affairs (UN-OOSA) Forum for multi-lateral discussions …promote cooperation, as appropriate, on matters of mutual interest related to civilian satellite-based positioning, navigation, timing and value-added services, as well as the compatibility and interoperability of global navigation satellite systems, while increasing their use to support sustainable development, particularly in developing countries ICG Participants are system providers, international governmental organizations and international non-governmental organizations Opportunity for users - and high end scientific user community - to interact with system providers Challenges, cont.

17. PRESS RELEASE—DRAFT Thursday 23 October 2008, 18.00 Global Science community agrees on first steps to establish a global virtual system for scientific data Scientific organisations representing over one hundred and thirty countries agree to overhaul existing world data centres and services to create a World Data System Maputo, Mozambique—the existing networks for collecting, storing and distributing data in many areas of science are inadequate and not designed to enable the inter-disciplinary research that is necessary to meet major global challenges. These networks must be transformed into a new inter-operable data system and extended around the world and across all areas of science. The General Assembly of the International Council for Science (ICSU) agreed today to take the first strategic steps to establish such a system. More scientific data and information is now available than at any other time in history and the volume is increasing daily, particularly via the World Wide Web. Yet the quality, long-term stewardship and availability of this data is largely uncertain and a large amount of valuable scientific data remains inaccessible. Over 50 years ago, ICSU established networks of data centres and services to provide full and open access to scientific data and products for the global community. But the world has changed enormously in 50 years, most notably with advances in technology, and it is time for the existing structures to be integrated into a new expanded system—a World Data System. The expert report recommending the new system and presented to the ICSU General Assembly asserts: ‘there is a need for global federations of professional state of the art data management institutions, working together and exchanging practices. Such federations can provide quality assurance and promote data publishing, providing the backbone for a global virtual library for scientific data’. The report concludes that ICSU itself can play a leading role by re-structuring its own data bodies. Ray Harris, chair of the expert Committee that produced the report said, ‘Data is the lifeblood of science and there are many exciting developments, which means that access to scientific data both for science and for policy making should be much easier. However, in many areas there is little order and the origin and reliability of what one finds on the web can be almost impossible to determine’. ‘A more strategic and systematic international approach, together with significant financial investment at the national level, is urgently required if we are to realise the full benefit of science for society,’ Harris continued.

18. Dave Carlson, the Director of the programme office for the International Polar Year (IPY)—a major, ICSU-sponsored, interdisciplinary research programme that is using and generating enormous amounts of data—added: ‘There are more than 200 IPY research projects, funded to the tune of 1.5 billion Euros, and its major legacy should be the data that will inform polar research for years to come. But we still don’t know how most of this data will be handled’. ‘The new ICSU World Data System should help provide at least part of the answer. A little bit of extra resource for data management is urgently needed to ensure maximum return on what has been a huge public investment in IPY.’ ICSU will be implementing the recommendations in the report over the next three years. The report is available at: http://www.icsu.org/Gestion/img/ICSU_DOC_DOWNLOAD/2123_DD_FILE_SCID_Report.pdf Media enquiries Jacinta Legg, Science Communications Officer, ICSU. jacinta.legg@icsu.org, Tel: +33 1 45255777. For journalists at the General Assembly, contact: Gisbert Glaser, Tel: +33 6 32310027. About ICSU Founded in 1931, ICSU is a non-governmental organization with a global membership of national scientific bodies (114 Members, representing 134 countries) and International Scientific Unions (29 Members). The Council is frequently called upon to speak on behalf of the global scientific community and to act as an advisor in matters ranging from the environment to conduct in science. ICSU’s activities focus on three areas: planning and coordinating research; science for policy; and strengthening the Universality of Science.

19. GGOS Support of Earth system science is fundamental driving principle Provides a framework for multi-disciplinary investigations to address critical scientific issues in coming decades Maintains, evolves and extends the precise reference frame to relate all observations Long-term stewardship of data, information and data analysis products is key objective Long-term geodetic time series Bridging digital divide with developing countries and pacing science and technical developments Summary & Outlook

20. http://www.ngs.noaa.gov/IGSWorkshop2008/ http://sidt.gpsworld.com/gpssidt/Expert+Advice+%26+Leadership+Talks/Expert-Advice-Reference-Frame-for-Africa/ArticleStandard/Article/detail/545022 Some Weblinks

21. Backup Slides

22. Global Geodetic Observing System (GGOS) • GGOS Working Groups • Networks & Communications • Data & Information • Missions • Conventions, Analysis • Outreach • Regional • Associations • European Combined Geodynamic Network • Nordic Geodetic Observing System IAG Commissions • 1: Reference Frames • 2: Gravity Field • 3: Earth Rotation & Geodyn. • 4: Positioning & Applications Strategy & planning Regional implementation • GGOS • Steering Committee • Science Panel • Executive Committee • Secretariat Scientific &tech. innovation Societal relevance • IGOS-P • Contributions to existing Themes • New Theme:„Earth System Dynamics“ Infrastructure, service, products • IAG Services • IGS, IVS, ILRS, IDS, IERS • IGFS, IGeS, BGI, GGP • PSMSL, IAS, BIPM, IBS Integration • GEO and GEOSS • GGOS Contribution to • GEO Plenary • GEO Committees & WGs • GEO Work plan tasks USERS

23. Model of the Interactions in the Earth System Tides of the solid Earth Global vegetation Lunisolar Gravitational acceleration Oceanic tides Ocean currents Global ground water Density variations in the atmosphere Snow Ocean loading Atmospheric tides Deformation of the Earth Postglacial land uplift Angular torques Atmospheric loading … Angular momentum variation of the oceans Tectonic plate motion Angular momentum variation of the atmosphere Volcanism Pole tides Earthquakes Rotation of the Earth Gravity Field of the Earth Effects from Earth interior