Investigation of sub-daily and episodic variations of Earth rotation observed by VLBI, ring laser gyroscopes and GNSS

• Applicants: Privatdozent Dr.-Ing. Axel Nothnagel; Professor Dr. Markus Rothacher; Professor Dr.-Ing. Harald Schuh
• Co-Applicant: Professor Dr. Robert Weber
• Subject Area: Geophysics and Geodesy
• Term: from 2006 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5471782

The primary objectives of project SPEED are to observe high-quality Earth rotation parameter (ERP) series over at least three years with a time resolution of one hour or less derived from various modern geodetic techniques, namely GNSS (GPS+GLONASS), VLBI, and ring laser gyroscopes, and to provide a concise interpretation of these series. The investigations will concentrate on an almost complete modeling of atmospheric and oceanic phenomena, which are the most likely source of short period variations of Earth rotation with periods of few days down to few hours. Because of the unprecented resolution of the observed ERP time series and the detailed modeling of atmospheric and oceanic excitation based on geophysical data quasi-periodic, a-periodic, and episodic variations of the ERP should be detectable for the first time. Within each technique validation of the results using different software packages for the same data and analyzing these data independently by two analysis centers will provide highest robustness and reliability.

• DFG Programme: Research Units
• Subproject of: FOR 584: Earth Rotation and Global Dynamic Processes
• International Connection: Austria, Switzerland