Regional grids : Bay of Biscay, France

This page provides a package of 1'x1' resolution free-air gravity and geoid models determined at BGI (Vu et al.) for the Bay of Biscay (France). It includes the data derived from an airbone absolute gravity survey realized in Spring 2019 with the cold-atom gravity meter GIRAFE (Bidel et al., 2023). Quasigeoid computations are based on the remove-restore procedure, namely the Stokes integral using the Fast Fourier Transform approach and deterministic kernel modification proposed by Wong–Gore. The grid models resulting from the combination of heterogeneous airborne, ground & satellite data are performed as follows :

(1) 1'x1' Free-air gravity anomaly models :
- GIRAFE merged Terrestrial gravity data : Free Air anomaly is denoted as FABC_GIRAFE
- DTU21 merged Terrestrial gravity data : Free Air anomaly is denoted as FABC_DTU21
- UCSDv31 merged Terrestrial gravity data : Free Air anomaly is denoted as FABC_UCSDv31
- Debiased shipborne merged Terrestrial gravity data : Free Air anomaly is denoted as FABC_shipborne(db).

(1) 1'x1' quasigeoid models :
- GIRAFE merged Terrestrial gravity data : estimated quasigeoid denoted as QBC_GIRAFE
- DTU21 merged Terrestrial gravity data : estimated quasigeoid denoted as QBC_DTU21
- UCSDv31 merged Terrestrial gravity data : estimated quasigeoid denoted as QBC_UCSDv31
- Shipborne without debiased merged Terrestrial gravity data : estimated quasigeoid denoted as QBC_shipborne
- Debiased shipborne merged Terrestrial gravity data : estimated quasigeoid denoted as QBC_shipborne(db)
- GIRAFE merged DTU21 removing the grid points within 10 km from coastline and Terrestrial gravity data : estimated quasigeoid denoted as QBC_GIRAFE_DTU21(r)
- GIRAFE merged UCSDv31 removing the grid points within 10 km from coastline and Terrestrial gravity data : stimated quasigeoid denoted as QBC_GIRAFE_UCSDv31(r)
- GIRAFE merged debiased shipborne and Terrestrial gravity data : estimated quasigeoid denoted as QBC_GIRAFE_shipborne(db)