Enhanced geopotential field modelling as basis for the establishment of precise height systems (Geo-H)

• Applicants: Professor Dr. Roland Pail; Dr.-Ing. Laura Sanchez-Drewes; Professor Dr.-Ing. Michael Schmidt
• Subject Area: Geodesy, Photogrammetry, Remote Sensing, Geoinformatics, Cartography
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 468696263

A current challenge of Geodesy is the implementation of an integrated Global Geodetic Reference Frame (GGRF) that supports the coherent determination and monitoring of the Earth’s geometry, rotation, and gravity field changes with high accuracy worldwide as defined by the International Association of Geodesy (IAG) and declared by the United Nations Resolution on a GGRF for Sustainable Development in 2015. The main objective of the project Geo-H is to develop the methodological foundation for the realization of modern geopotential-based height systems in agreement with the definitions of a global International Height Reference System (IHRS) as a main requirement to advance towards the GGRF. Based on the expertise of the “Ingenieurinstitut für Astronomische und Physikalische Geodäsie” (IAPG) and the “Deutsches Geodätisches Forschungsinstitut der Technischen Universität München” (DGFI-TUM) on high-resolution gravity field and regional geoid modelling, we aim at (1) quantifying with high reliability the error budget of the physical height determination,(2) developing new concepts and methods towards improved geopotential solutions and their accuracy assessment, and (3) providing scientific guidelines and a roadmap for the realization of globally consistent geopotential-based height systems. The project is built on three cornerstones: (1) Error budget analysis from the validation of regional geopotential (geoid) models by means of comparison to independent observations and the identification/reduction of systematic errors associated to different geoid modelling methods. (2) Improvement of stochastic models, spectral combination and optimal weighting of gravity data of different resolutions to implement rigorous error propagation analyses in the determination of geopotential (geoid) models. (3) Compilation of a scientific concept for the establishment, maintenance, and long-term sustainability of geopotential-based height systems, with emphasis in the establishment of the global IHRS. Methodologies, developments and findings of Geo-H will be placed on international level as baseline methods, to be used as guidelines for science and administration in the realization of the IHRS, and more general, in the realization of geopotential-based height systems.

• DFG Programme: Research Grants
• Co-Investigators: Dr.-Ing. Denise Dettmering; Dr.-Ing. Thomas Gruber