Refinements in the Combined Adjustment of Satellite Altimetry and Gravity Anomaly Data
Abstract
One of the most important objectives accomplished during the present analysis has been the upgrading of the AFGL computer program SAGG (Satellite Altimetry and Ground Gravity). This program serves in the determination of the global geoid and the earth's gravity field, based on the combination of satellite altimetry observations and gravity anomalies. A typical feature of SAGG is the simultaneous recovery of both the orbital parameters and the spherical harmonic potential coefficients. The short arc adjustment mode makes these determinations possible without the requirement of highly precise reference orbits. An important refinement in SAGG has been the differentiation of the radial distance to a sub-satellite geoidal point with respect to the state vector parameters. A practical benefit of this feature is faster convergence in the adjustment. The new version of SAGG has been used in a combined adjustment of real data, in conjunction with a (14, 14) geopotential model. Comparison of internal precision has demonstrated the beneficial effect of adding altimetry data to the existing body of gravity anomaly data. The recovered geoid over most of the globe shows good agreement with gravimetric geoids obtained from independent sources. This is especially true of the areas covered by the GEOS-3 satellite when compared with the earlier reported results of the AFGL computer program SARRA.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 12, 1977
- Accession Number
- ADA047597
Entities
People
- Georges Blaha