Modelling atmospheric and induced non-tidal oceanic loading contributions to surface gravity and tilt measurements

Abstract

, et al.. Modelling atmospheric and induced non-tidal oceanic loading contributions to surface gravity and tilt measurements. Journal of Geodynamics, Elsevier, 2009, 48 (3-5) This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AbstractWe investigate the contribution of atmospheric and its induced non-tidal oceanic loading effects on surface time-varying gravity and tilt measurements for several stations in Western Europe. The ocean response to pressure forcing can be modelled accordingly to the inverted barometer, i.e. assuming that air pressure variations are fully compensated by static sea height changes, or using ocean general circulation models. We validate two runs of the HUGO-m barotropic ocean model by comparing predicted sea surface height variations with hundred tide gauge measurements along the European coasts. We thenshow that global surface pressure field, as well as a barotropic high-resolution ocean model forced by air pressure and winds allow in most cases a significant reduction of the variance of gravity residuals and, to a smaller extends tilt residuals. Page 2 of 24A c c e p t e d M a n u s c r i p tWe finally show that precise gravity measurements with superconducting gravimeters allow the observation of large storm surges, occurring in the North Sea, even for inland stations. However, we also confirm that the continental hydrology contribution cannot be neglected. Thanks to their specific sensitivity feature, only tiltmeters closest to the coast can clearly detect the loading due to these storm surges.

Water storage changes as a marker for base flow generation processes in a tropical humid basement catchment (Benin): Insights from hybrid gravimetry

“…This loading contribution is evaluated for angular distances larger than 0.258 from the station (called the ''nonlocal'' part) and the local contribution is computed from the local pressure records and a nominal admittance in the 0.258 radius ''cylinder'' around the station from the same loading model (23.06679 nm/s 2 /hPa). The ocean response is included in the nonlocal calculation using the MOG2D nontidal ocean model [Carrère and Lyard, 2003] which has shown to perform better than the classical inverted barometer hypothesis [Boy and Lyard, 2008;Boy et al, 2009]. Details of atmospheric corrections for the Djougou SG station can be found in Hinderer et al [2014b] and Hector et al [2014].…”

Resolving Geophysical Signals by Terrestrial Gravimetry: A Time Domain Assessment of the Correction‐Induced Uncertainty

“…The nontidal ocean loading effects were acquired from EOST Loading Service (Boy et al, ) utilizing ECCO‐JPL (Fukumori, ), ECCO2 (Menemenlis et al, ), and TUGOm (Loren & Florent, ) models (download at loading.u-strasbg.fr, access date 28 February 2018). In addition, nontidal ocean mass variations of the OMCTv06 model (Dobslaw et al, ) were converted to their gravity effect using mGlobe.…”

Ocean tide, Baltic Sea and atmospheric loading model tilt comparisons with interferometric geodynamic tilt observation - case study at Lohja2 geodynamic station, southern Finland

“…5) contains a large 120 nanoradian tilt oscillation following the great magnitude 9.0 Tohoku-Oki earthquake in 11.3.2011 (Japan). The atmospheric loading tilt time series was provided by Boy et al (2009) and it is compared also to de-tided tilt meter observations described above (Fig. 4).…”

“…Recent atmospheric and nontidal ocean loading time series for gravity and tilt is available e.g. by Boy et al (2009). They modelled ocean response to air pressure variation according to the inverted barometer principle and taking into account general ocean circulation.…”