| タイトル | Gravity model development for TOPEX/POSEIDON: Joint gravity models 1 and 2 |
| 著者（英） | Pavlis, E. C.; Tapley, B. D.; Lerch, F. J.; Eanes, R. J.; Marshall, J. A.; Ries, J. C.; Nerem, R. S.; Putney, B. H.; Schutz, B. E.; Shum, C. K. |
| 著者所属（英） | NASA Headquarters; Jet Propulsion Lab., California Inst. of Tech.; NASA Goddard Space Flight Center |
| 発行日 | 1994-12-15 |
| 言語 | eng |
| 内容記述 | The TOPEX/POSEIDON (T/P) prelaunch Joint Gravity Model-1 (JGM-1) and the postlaunch JGM-2 Earth gravitational models have been developed to support precision orbit determination for T/P. Each of these models is complete to degree 70 in spherical harmonics and was computed from a combination of satellite tracking data, satellite altimetry, and surface gravimetry. While improved orbit determination accuracies for T/P have driven the improvements in the models, the models are general in application and also provide an improved geoid for oceanographic computations. The postlaunch model, JGM-2, which includes T/P satellite laser ranging (SLR) and Doppler orbitography and radiopositioning integrated by satellite (DORIS) tracking data, introduces radial orbit errors for T/P that are only 2 cm RMS with the commission errors of the marine geoid for terms to degree 70 being +/- 25 cm. Errors in modeling the nonconservative forces acting on T/P increase the total radial errors to only 3-4 cm root mean square (RMS), a result much better than premission goals. While the orbit accuracy goal for T/P has been far surpassed geoid errors still prevent the absolute determination of the ocean dynamic topography for wavelengths shorter than about 2500 km. Only a dedicated gravitational field satellite mission will likely provide the necessary improvement in the geoid. |
| NASA分類 | OCEANOGRAPHY |
| レポートNO | 95A80697 |
| 権利 | Copyright |
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