References of "Boy, Jean-Paul"
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See detailSpatial–temporal variations of water vapor content over Ethiopia: a study using GPS observations and the ECMWF model
Abraha, Kibrom Ebuy UL; Lewi, Elias; Masson, Frederic et al

in GPS Solutions (2015)

We characterize the spatial–temporal variability of integrated water vapor (IWV) in Ethiopia from a network of global positioning system (GPS) stations and the European Center for Medium range Weather ... [more ▼]

We characterize the spatial–temporal variability of integrated water vapor (IWV) in Ethiopia from a network of global positioning system (GPS) stations and the European Center for Medium range Weather Forecasting (ECMWF) model. The IWV computed from the ECMWF model is integrated from the height of the GPS stations on 60 pressure levels to take both the actual earth surface and the model orography discrepancies into account. First, we compare the IWV estimated from GPS and from the model. The bias varies from site to site, and the correlation coefficients between the two data sets exceed 0.85 at different time scales. The results of this study show that the general ECMWF IWV trend is underestimation over highlands and overestimation over lowlands for wet periods, and overestimation over high- lands and underestimation over lowlands for dry periods with very few exceptional stations. Second, we observe the spatial variation of the IWV. High values are obtained in those stations that are located in the north-eastern (Afar depression) sites and the south-western part of the country. This distribution is related to the spatial variability of the climate in Ethiopia. Finally, we study the seasonal cycle and inter-annual variability of IWV for all stations over Ethiopia. The main result is the strong inter-annual vari- ability observed for the dry seasons. [less ▲]

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See detailGravity Tide and seasonal gravity variation at Ny-Alesund, Svalbard In Arctic
Sato, Tadahiro; Boy, Jean-Paul; Tamura, Yoshiaki et al

in Journal of Geodynamics (2006), 41(1-3), 234-241

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See detailThe New IERS Special Bureau for Loading (SBL)
van Dam, Tonie UL; Plag, Hans-Peter; Blewitt, Geoffrey et al

in International VLBI Service for Geodesy and Astrometry: General Meeting Proceedings (2002)

Currently, the establishment of the International Earth Rotation Service (IERS) Special Bureau for Loading (SBL) is in progress as part of the IERS Global Geophysical Fluids Center (GGFC). The main ... [more ▼]

Currently, the establishment of the International Earth Rotation Service (IERS) Special Bureau for Loading (SBL) is in progress as part of the IERS Global Geophysical Fluids Center (GGFC). The main purpose of the SBL is to provide reliable, consistent model predictions of loading signals that have been thoroughly tested and validated. The products will describe at least the surface deformation, gravity signal and geo-center variations due to the various surface loading processes in reference frames relevant for direct comparison with existing geodetic observing techniques. To achieve these goals, major scientific advances are required with respect to the Earth model, the theory and algorithms used to model deformations of the Earth as well as improvements in the observational data related to surface loading. [less ▲]

Detailed reference viewed: 80 (3 UL)