Relevant links:



NOTE: The official GGOS web pages are at http://www.ggos.org. Note that these pages have not been maintained by GGOS over the last five years and are somewhat out-dated.

If you are looking for the former "GGOS Work Web Site", you can find it here.

US-GEO has released its national report on Earth observations, which identifies 17 critical Earth system parameters that must be observed from space. Among them are gravity, soil moisture, deformations, and sea level. See U.S. Co-Chair Shere Abbott’s blog on the White House Office of Science and Technology website for more information and a copy of the report Achieving and Sustaining Earth Observations: A Preliminary Plan Based on a Strategic Assessment by the U.S. Group on Earth Observations ...

The article "The global geodetic observing system (GGOS): detecting the fingerprints of global change in geodetic quantities" by Hans-Peter Plag et al. has been published in the book "Advances in Earth Observation of Global Change", edited by Emilio Chuvieco, Jonathan Li, and Xiaojum Yang. See Springer announcement for details.

The "GGOS 2020 Book" a reference: The book "Global Geodetic Observing System: Meeting the Requirements of a Global Society on a Changing Planet in 2020", edited by Hans-Peter Plag and Michael Pearlman, which was published by Springer in 2009, gives an excellent overview of what geodesy can do for science, society, and you. It also sets the frame for the development of the global geodetic infrastructure and what actions the global geodetic community needs to take in order to fully exploit the potential of geodesy in a modern society. See http://www.springer.com/978-3-642-02686-7 for details. On-line version.

For geophysical and geodetic details on the April 4, 2010 Northern Mexico earthquake, visit the Baja SuperSite Page ...

Visit the web site of the USGS for the Baja California, Mexico earthquake ...

For geophysical and geodetic details on the Chile Earthquake, visit the Chile SuperSite Page ...

Visit the web site of the Geohazards Community of Practice (GHCP) of the Group on Earth Observations (GEO) ...

Read Bente Lilja Bye's article on The Haiti Earthquake: Science, Early Warning And Mitigation...

For geophysical and geodetic details, visit the Haiti SuperSite Page ...

Speaking of the Global Geodetic Observing System we refer to two rather different things, and we need to be clear in what we specifically mean:

  1. The Global Geodetic Observing System (GGOS) of the International Association of Geodesy (IAG) is an organizational component of the IAG structure and represents the observing system of IAG. This system is built upon the many IAG Services that represent individual techniques and/or products. The GGOS organization provides a governing structure, working groups, bureaus, and coordination entities. Through the IAG Services, GGOS coordinates global infrastructure (geodetic networks, data archives, and processing and analysis centers), and makes available products mainly for scientific users but also, to a limited extent, for society at large. Resources for GGOS are provided by many national agencies, research institutions and individuals on a best-effort basis.
  2. The global geodetic observing system (ggos) has a much broader meaning and comprises all global geodetic infrastructure owned, maintained, and controlled by many. This term covers items such as the Global Navigation Satellite Systems (GNSSs) (GPS, GLONASS, Galileo, ...), different satellites developed, deployed and operated by space agencies in many countries, ground-based networks of tracking stations and other geodetic infrastructure, air-borne surveys, and many more. Many scientific teams process the geodetic observations and make global geodetic products available in various ways. Coordination of these global activities happens in many different ways, often also on regional level.

See the video Earth Observations and Earthquakes produced by Bente Lilja Bye for Astrocast-TV: .

If the above screen doesn't work, try here ....


About these pages: This web site makes available material related to geodesy and the global geodetic infrastructure in general. In particular, these pages aim to give a comprehensive picture of ggos. They also provide some information on GGOS. Up to January 2010, the GGOS-related material at this site was made available as a documentation and in support of the work of the GGOS Steering Committee, Executive Committee, Working Groups, Science Panel, GEO representatives, and special projects or activities. These pages are now archived and no longer updated. Moreover, these pages are not official pages of GGOS. For the offical pages of GGOS go to www.ggos.org.

Read more about the background of the pages ...

Recent news: Recent news items on events, decisions, meetings, and publications related to geodesy, ggos, and GGOS are available at the News page ...

Some of my recent presentations related to geodesy, the global geodetic infrastructure and GGOS include:
Plag, H.-P.: Theme 3: Sea-level change, variability and forecasting,
Plag, H.-P.: GEO Meetings and IGOS Symposium,
Plag, H.-P. et al.: A Roadmap for Future Satellite Gravity Missions,


Geodesy blogs:

Last edited 31 December 2010

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