A comparison of altimeter and gravimetric geoids in the Tonga Trench and Indian Ocean areas |
| |
| Authors: | Richard H Rapp |
| |
| Institution: | (1) Department of Geodetic Science, The Ohio State University, 1958 Neil Ave, 43210 Columbus, Ohio |
| |
| Abstract: | A gravimetric geoid computed using different techniques has been compared to a geoid derived from Geos-3 altimeter data in
two 30°×30° areas: one in the Tonga Trench area and one in the Indian Ocean. The specific techniques used were the usual Stokes
integration (using 1°×1° mean anomalies) with the Molodenskii truncation procedure; a modified Stokes integration with a modified
truncation method; and computations using three sets of potential coefficients including one complete to degree 180. In the
Tonga Trench area the standard deviation of the difference between the modified Stokes’ procedure and the altimeter geoid
was ±1.1 m while in the Indian Ocean area the difference was ±0.6 m. Similar results were found from the 180×180 potential
coefficient field. However, the differences in using the usual Stokes integration procedure were about a factor of two greater
as was predicted from an error analysis.
We conclude that there is good agreement at the ±1 m level between the two types of geoids. In addition, systematic differences
are at the half-meter level. The modified Stokes procedure clearly is superior to the usual Stokes method although the 180×180
solution is of comparable accuracy with the computational effort six times less than the integration procedures. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
