The reduction of hydrology-induced gravity variations at sites with insufficient hydrological instrumentation

Autor(en)
Michal Mikolaj, Bruno Meurers, Marcel Mojzeš
Abstrakt

The hydrology-induced gravity variation is a limiting factor in the study of geophysical phenomena with superconducting gravimeters. The goal of this paper is to analyse and reduce the hydrological effects on gravity at the Vienna (Austria) station that is a typical example of a site insufficiently equipped with hydro-meteorological sensors. The hydrological effects are studied in a local as well as a global scale. A new method for computing the local soil moisture effect is presented. This approach overcomes the lack of in situ soil moisture observations and utilizes gravity residuals in the calibration process of a local conceptual 1D soil moisture model. In addition, only a priori soil moisture variations, provided by a global hydrological model, in situ temperature, precipitation and snow height time series are required in this approach. The coupling of the calibration process to gravity residuals increases the sensitivity of the modelled soil moisture to corrections that are applied within the processing of the gravity observations. This is shown in this study using different global hydrological corrections. The differences between these corrections are reflected in the modelled soil moisture so that the total hydrological effect (local plus global) is almost identical. The total hydrological effects reduce the observed gravity variation by 30%. Moreover, both seasonal as well as short-term variations clearly related to observed hydro-meteorological parameters are minimized. On the other hand, the sensitivity of the modelled soil moisture to gravity corrections implies that the long-term gravity residuals are not suitable for local hydrological studies unless the significant differences between the global hydrological corrections are resolved

Organisation(en)
Institut für Meteorologie und Geophysik
Externe Organisation(en)
Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum, Slovak University of Technology in Bratislava
Journal
Studia Geophysica et Geodaetica: a journal of geophysics, geodesy, meteorology and climatology
Band
59
Seiten
424-437
Anzahl der Seiten
14
ISSN
0039-3169
DOI
https://doi.org/10.1007/s11200-014-0232-8
Publikationsdatum
07-2015
Peer-reviewed
Ja
ÖFOS 2012
105102 Allgemeine Geophysik
Schlagwörter
ASJC Scopus Sachgebiete
Geochemistry and Petrology, Geophysics
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/the-reduction-of-hydrologyinduced-gravity-variations-at-sites-with-insufficient-hydrological-instrumentation(9b93270c-4d02-4d3d-a2df-e479ae23fcbe).html