PG

Physical Geodesy

 
Gravity meter A10
Measurement of absolute gravity with gravity meter A10.

One of the central objectives of geodesy is the determination of the Earth’s gravity field. The gravity field is generated through the sum of the mass distribution created through gravitation potential and the centrifugal potential as a result of the Earth’s rotation. The non disturbed ocean surface can be seen as a first approach to visualizing the equipotential of the gravity field. In the past this field was considered to be the zero reference point for our height systems. Presently the zero reference point is being defined through established terrestrial coordinates and their defined potential value. The gradient of the gravity field is the acceleration measured by gravimeter. The gravimeter measurements and the satellite observations are now the basis for the calculation of the gravity field. Special satellite missions, such as GRACE and GOCE, have enabled us to observe gravity field variations and also the possible causes for the deviations, such as climate change with geophysical and hydrological effects. Research at PSG is involved in the following subjects:

  • Gravimetry
  • Geoid determination
  • Mass transport in system Earth

Contact person: Prof. Dr.-Ing. Matthias Becker

satellite GRACE
GRACE satellite pair for measurement of the Earth's gravity field (picture: NASA)