Commission 1. Reference Frames

1. Establishment, maintenance, improvement of the geodetic reference frames.


2. Advanced terrestrial and space observation technique development for the above purposes.


3. International collaboration for the definition and deployment of networks of terrestrially-based space geodetic observatories.


4. Theory and coordination of astrometric observation for reference frame purposes.


5. Collaboration with space geodesy/reference frame related international services, agencies and organizations.

Commission 2. Gravity Field

1. Terrestrial, marine, and airborne gravimetry.


2. Satellite gravity field observations.


3. Gravity field modeling.


4. Time-variable gravity field.


5. Geoid determination.


6. Satellite orbit modeling and determination.

Commission 3. Earth Rotation and Geodynamics

1. Earth Orientation (Earth rotation, polar motion, nutation and precession).


2. Earth tides.


3. Tectonics and Crustal Deformation.


4. Sea surface topography and sea level changes.


5. Planetary and lunar dynamics.


6. Effects of the Earth's fluid layers (e.g., post glacial rebound, loading).

Commission 4. Positioning and Applications

1. Terrestrial and satellite-based positioning systems development, including sensor and information fusion.


2. Navigation and guidance of platforms.


3. Interferometric laser and radar applications (e.g., Synthetic Aperture Radar).


4. Applications of geodetic positioning using three dimensional geodetic networks (passive and active networks), including monitoring of deformations.


5. Applications of geodesy to engineering.


6. Atmospheric investigations using space geodetic techniques.

Intercommission Committee on Theory

As a result of the IAG restructuring, and recognizing that geodetic observing systems have advanced to such an extent that geodetic measurements:

• are now of unprecedented high accuracy and quality, can readily cover a region of any scale up to tens of thousands of kilometres, consist of non-conventional data types, and can be provided continuously; and


• consequently, demand new mathematical modelling in order to obtain best possible benefit of such technological advance, the ICCT

1. strongly encourages frontier mathematical and physical research, directly motivated by geodetic need/practice, as a contribution to science/engineering in general and the foundations for Geodesy in particular;


2. provides the channel of communication amongst the different IAG entities of commissions /services/ projects, on the ground of theory and methodology, and directly cooperate with and support these entities in the topics-oriented work;


3. helps the IAG in articulating mathematical and physical challenges of geodesy as a subject of science and in attracting young talents to geodesy. The ICCT should certainly try to attract and serve as home to mathematically motivated/oriented geodesists and to applications-oriented applied mathematicians; and


4. encourages closer research ties with and directly gets involved with relevant areas of the Earth Sciences, bearing in mind that geodesy has been playing an important role in understanding the physics of the Earth.