SESSION 7:

"The Global Geodetic Observing System: Science and Applications
Convenors:
Richard Gross (Jet Propulsion Laboratory, USA; Richard.Gross@jpl.nasa.gov)
Hans-Peter Plag (University of Nevada at Reno, USA; hpplag@unr.edu)
Luiz Paulo Fortes (Instituto Brasileiro de Geografia e Estatística, Brazil;fortes@ibge.gov.br)

SUB-SESSIONS:
- 7.1: Past Progress and Future Plans

Convenors:
Hans-Peter Plag (University of Nevada at Reno, USA; hpplag@unr.edu)
Richard Gross (Jet Propulsion Laboratory, USA; Richard.Gross@jpl.nasa.gov)
Luiz Paulo Fortes (Instituto Brasileiro de Geografia y Estatística, Brazil;fortes@ibge.gov.br)

The Global Geodetic Observing System (GGOS) was established by IAG in 2003 initially as a Project, and after a
period of planning and implementation, in 2007, GGOS was integrated in the structure of IAG components as the
Observing System of IAG. Main milestones during these first years are the definition and implementation of an
organizational structure, a number of science and outreach workshops, representation of IAG in and contributions
to the Group on Earth Observation (GEO), and the compilation of the GGOS 2020 book, with the latter describing
the future organization and design of GGOS. By the time of the IAG meeting, several new elements will already
have been implemented. The session will review the past progress, and we invited papers that critically assess all
aspects of the development of GGOS both as an organization and as an observing system. Of particular interest
are presentations of shareholders (IAG Commissions and Services) which address their interactions with GGOS,
and of stakeholders, which address present and future benefits of GGOS for them. The session will also provide
room for the discussion of future plans of GGOS, including potential future contributions of IAG components or
other groups.

- 7.2: Science and Applications

Convenors:
Richard Gross (Jet Propulsion Laboratory, USA; Richard.Gross@jpl.nasa.gov)
Hans-Peter Plag (University of Nevada at Reno, USA; hpplag@unr.edu)
Luiz Paulo Fortes (Instituto Brasileiro de Geografia e Estatística, Brazil; fortes@ibge.gov.br)

Measurements of the Earth's rotation, shape, and gravity provided by the Global Geodetic Observing System
(GGOS) show that they change on a wide range of time scales reflecting the wide range of processes affecting
them, from external tidal forces to surficial processes involving the atmosphere, oceans, and hydrosphere to
internal processes acting both at the core-mantle boundary as well as within the solid Earth itself. Measurements
of the Earth's rotation, shape, and gravity can therefore be used to gain greater scientific understanding of these
processes. They can also be applied to address societally important issues such as climate change, global
warming, and sea level rise. This session will be a forum for discussing the science and applications of Earth
rotation, shape, and gravity measurements provided by GGOS.