The Collaborative Research Centre 1464 "TerraQ" at Leibniz University Hannover is developing new measurement techniques, sensors and analysis methods to significantly improve gravimetric Earth monitoring both with observations from space and on the ground that thus document climate change processes with unprecedented accuracy. TerraQ scientists have many years of expertise in the fields of laser interferometry in space, the development of quantum sensors and optical clocks, and geodetic modeling. The central goal of TerraQ is the development of new measurement techniques and analysis methods in order to be able to determine variations in the Earth's gravitational field with unprecedented accuracy. For this purpose, the gravity field variables are modeled geodetically and relativistically, and relevant application scenarios are simulated in order to show the superior performance of the newly developed measurement concepts compared to existing approaches.

Those novel data-sets of satellite-based and terrestrial measurements are analyzed for both random and systematic errors, and are subsequently integrated into the gravity field determination process. In addition, the potential of optical clock networks will be demonstrated, enabling the direct determination of gravitational potential differences on short time scales and on various length scales, thus defining a completely new type of elevation systems as part of future unified geodetic reference systems.

Section 1.3 contributes to TerraQ by means of one subproject for the creation of improved background models of atmospheric mass variability for terrestrial gravimetry. In particular, we will aim for increased accuracy in the modeling of atmospheric attraction effects in the immediate near field of gravimeters. Furthermore, the section provides significant contributions to the modelling of oceanic tidal signals in long time series of superconducting gravimeters.

Funding Agency: German Research Foundation (DFG)

Laufzeit: 01.01.2021 until 31.12.2024

Website: https://www.terraq.uni-hannover.de/