Glacial isostatic adjustment (GIA) describes the response of the solid earth to ice mass changes and corresponding changes in the sea level. This process is visible in various geoscientific observations, with geodetic measurements being crucial to understand and describe the process. For example, the vertical and horizontal motion of the lithosphere is visible in GNSS (Global Navigation Satellite Systems) time series in the currently (Greenland, Antarctica, Svalbard) and formerly glaciated regions (North America, northern Europe). In addition to geodetic observations of GIA, the solid earth deformation is visible in various geological data. The vertical motion of the lithosphere can be seen in relative sea level and lake level data, but for a different epoch then GNSS data. All these observations help to explain GIA as well as infer the structure of the Earth via so-called GIA models. GIA models can be constrained by geodetic and geological observations and in turn can help to predict these observations. An essential component of GIA models is knowledge about the distribution of material parameters of the Earth’s lithosphere and mantle. This can be obtained from various geophysical measurements (e.g., gravity, seismology).

Here, I will show how we can infer the depth of various material layers in the lithosphere from geodetic data exemplary for Greenland and how we can use these in three-dimensional GIA models. I will also discuss the effect of various lithosphere models on the modelled GNSS velocities.

How to cite: Steffen, R.: Geodesy meets tectonophysics: Advancing our estimates of glacial isostatic adjustment, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-11261, https://doi.org/10.5194/egusphere-egu23-11261, 2023.

Current developments in quantum physics and the application of general relativity open up advanced prospects for satellite geodesy, gravimetric Earth observation and reference systems and thus strongly help to meeting the geodesy challenges in a unique way. As Vening-Meinsz advanced gravimetry 100 years ago with his pendulum apparatus, quantum optics can push it further using atoms today. These novel concepts include the application of atom interferometry for realizing quantum gravimetry and gradiometry, the enhanced use of laser interferometry for inter-satellite tracking and accelerometry at future gravity field missions, and relativistic geodesy with clocks for the determination of gravity potential differences via gravitational redshift measurements.

We briefly illustrate those novel techniques and present in which fields geodesy and geosciences will benefit from them. We show various application areas ranging from the direct determination of physical heights and the monitoring of mass variations using clock networks up to the use of quantum technology for gravimetric Earth observation on ground and in space. Realizing these innovative methods is key to quantify climate change processes (groundwater changes, ice mass loss, seal level rise, etc.) with largely increased precision and resolution.

Finally, we would like to mention the IAG project “Novel Sensors and Quantum Technology for Geodesy (QuGe)” that advances those activities in close collaboration between geodesy and physics, see https://quge.iag-aig.org/  -  see also: Van Camp, M., Pereira dos Santos, F., Murböck, M., Petit, G., Müller, J. (2021): Lasers and Ultracold Atoms for a Changing Earth. EOS, 102, https://doi.org/10.1029/2021EO210673

Acknowledgment: This study has been funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy EXC 2123 Quantum Frontiers - Project-ID 90837967 and the SFB 1464 TerraQ - Project-ID 434617780.

How to cite: Müller, J.: Benefit of Quantum Technology for Geodesy, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5719, https://doi.org/10.5194/egusphere-egu23-5719, 2023.