Climate signals in Earth's Rotation: Impact on the interpretation of variations in Earth Orientation Parameters and their forecasting

• Applicant: Dr.-Ing. Laura Jensen
• Subject Area: Geodesy, Photogrammetry, Remote Sensing, Geoinformatics, Cartography
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 563754750

Although Earth's rotation appears to be uniform, it exhibits variations driven by processes in the atmosphere, oceans, land hydrosphere, and the solid Earth. These variations are described with Earth Orientation Parameters (EOP), such as polar motion, the difference between universal time and coordinated universal time, and Celestial Pole Offsets. The knowledge about EOP is crucial for orienting astronomical instruments, space mission planning, time-keeping and precise positioning both on Earth and in space. EOP are also insightful for research on Earth system dynamics. Some applications require not only accurate EOP observations but also predictions. Processes associated with climate change, including glacier melting, sea-level rise, and shifts in atmospheric circulation, contribute to mass redistribution on Earth and thus affect its rotational dynamics.This project aims to analyse the influence of climate signals on EOP variability and to explore ways to enhance both modelling and prediction. By leveraging data from satellite missions (GRACE/GRACE-FO), climate models (from CMIP6), and geophysical models, we will investigate how phenomena such as El Niño oscillations, glacier melting, and changes in terrestrial water storage impact Earth's rotation.The primary objective of the project is to evaluate the extent to which changes in EOP can be utilized as indicators of climate change. Furthermore, the research will assess how geophysical processes influence the accuracy of current EOP predictions and propose improvements, particularly by refining the modelling of effective angular momentum functions. The anticipated outcomes include improvement of geophysical models, enhanced EOP prediction accuracy, and a deeper understanding of the interconnections between climate change and Earth's rotational dynamics. The project will be implemented in cooperation between three Polish institutes and the German Research Centre for Geosciences (GFZ).

• DFG Programme: Research Grants
• International Connection: Poland
• Cooperation Partner: Professorin Dr. Jolanta Nastula