Multi-Satellite Altimeter Gravity Programme (Multi-Sat)

Building on over 20 years’ experience in processing satellite gravity data, we have completed a major programme to use new satellite data sets to develop the most accurate, reliable and coherent satellite-derived gravity data set over all the continental margins of the world.

For the first time in over 20 years, new satellite altimetry data are being acquired. The new data from the CryoSat-2, Jason-1 and AltiKa satellites mean a significant increase in data density, leading to a higher-resolution gravity field for the offshore regions of the globe.

The programme started in 2013 and was completed in July 2016.

multi satellite altimeter gravity study

Coverage map for Multi-Sat.

Multi-Sat

The programme incorporates new altimeter data from the geodetic missions of the CryoSat-2 and Jason-1 satellites, along with the ERS-1 and Geosat data sets from the 1980s. In addition, AltiKa data have been used in northern regions to improve coverage in areas where there is significant contamination by sea ice. The data from the three new satellites significantly increase the density of the satellite tracks on which the final solution is based.

Original track spacing compared to improved Multi-Sat track spacing.

Original track spacing (left) compared to improved multi-satellite track spacing (right).

The satellites have a range of orbital inclinations, such that the effective orbital spacing at the equator will reduce from ~5 km (2 satellites) to ~2 km (4 satellites). With all the data sets integrated, the resolution has improved  to sub-5 km half wavelength.

Deliverables

  • Digital 2 km grids of free-air gravity, Bouguer anomaly and isostatic anomaly
  • Digital 2 km grids of the new bathymetry compilation and the pseudo-bathymetry calculated from the new Multi-Sat gravity and bathymetry compilation
  • A technical report
  • ArcGIS products

To find out more about Multi-Sat, please Contact Us