Error variances-covariances of GEM-T1 - Their characteristics and implications in geoid computation

Details Error variances-covariances of GEM-T1 - Their characteristics and implications in geoid computation Error variances-covariances of GEM-T1 - Their characteristics and implications in geoid computation

Nov 1991

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1991jgr....9620011h&link_type=abstract

Journal of Geophysical Research (ISSN 0148-0227), vol. 96, Nov. 10, 1991, p. 20,011-20,022.

Statistics

Computation

9

Covariance, Earth Gravitation, Error Analysis, Geoids, Geopotential, Gravity Anomalies, Fast Fourier Transformations, Global Positioning System, Least Squares Method, Spherical Harmonics

Scientific paper

GEM-T1 is the first earth potential model for which a full error variance-covariance matrix of its coefficients was made available. This matrix offers the opportunity to look into the properties of the error covariance functions for geoid heights from GEM-T1. They appear to be rather anisotropic and inhomogeneous. Geoid error covariance functions are used in regional geoid computations, where usually a set of potential coefficients is combined with gravity anomalies. In order to see the effect of simplification of the error variance-covariance propagation in geoid computations, three cases were considered: the full matrix, the diagonal elements only, and the limitation to the use of error degree variances. The resulting variations in the estimated geoid errors are shown in two test areas for different cap sizes. They can reach 50 cm for a zero cap size. Finally, test computations are presented of geoid determination by least-squares collocation. Since the error covariance of the observations is included in the collocation operator, the geoid heights depend upon the choice of the type of error covariance propagation of the earth potential coefficient set, as it is a part of the observation. For the three considered cases, variations in the geoid heights amount up to 45 cm.

Affiliated with

Also associated with

No associations

Rating

Error variances-covariances of GEM-T1 - Their characteristics and implications in geoid computation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Error variances-covariances of GEM-T1 - Their characteristics and implications in geoid computation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Error variances-covariances of GEM-T1 - Their characteristics and implications in geoid computation will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1717953