Abstract
The Seasat altimeter data has been completely adjusted by a crossing arc technique to reduce the crossover discrepancies to approximately ±30 cm in five regional adjustments. This data was then used to create sea surface heights at 1° intersections in the ocean areas with respect to the GRS80 ellipsoid. These heights excluded the direct tidal effects but included the induced permanent deformation.
A geoid corresponding to these sea surface heights was computed, based on the potential coefficients of the GEML2 gravity field up to degree 6, augmented by Rapp’s coefficients up to degree 180. The differences between sea surface heights and the geoid were computed to give approximate estimates of sea surface topography. These estimates are dominated by errors in both sea surface heights and geoid undulations. To optimally determine sea surface topography a spherical harmonic analysis of raw estimates was carried out and the series was further truncated at degree 6, giving estimates with minimum wavelengths on the order of 6000 km.
The direction of current flow can be computed on a global basis using the spherical harmonic expansion of the sea surface topography. Ths has been done, not only for Seasat/GEML2 estimates, but also using the recent dynamic topography estimates of Levitus. The results of the two solutions are very similar and agree well with the major circulation features of the oceans.
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References
Coleman, R., “A Geodetic Basis for Recovering Ocean Dynamic Information from Satellite Altimetry”, Unisury S-19, School of Surveying, The University of New South Wales, Kensington, Australia, 1981.
Colombo, O, O., “Numerical Methods for Harmonic Analysis on the Sphere”, Department of Geodetic Science, Report No. 310, The Ohio State University, Columbus, 1981.
Engelis, T, T., “Analysis of Sea Surface Topography Using SEASAT Altimeter Data”, Department of Geodetic Science and Surveying, Report No. 343, The Ohio State University, Columbus, 1983.
Engelis, T., “Global Ocean Circulation from SEASAT Altimeter Data”, Marine Geodesy, 1984.
Lerch, F.N., S.M. Klosko and G.B. Patel, “A Refined Gravity Model from Lageos (GEML2)”, Geophysical Research Letters, Vol. 9, No. 11, pp. 1263–1266, 1982.
Levitus, S, S., “Climatological Atlas of the World Ocean”, NOAA, Geophysical Fluid Dynamics Laboratory, Professional Paper 13, Rockville, MD 1982.
Rapp, R.H, R.H., “The Earth’s Gravity Field to Degree and Order 180 Using SEASAT Altimeter Data, Terrestrial Gravity Data, and Other Data”, Department of Geodetic Science and Surveying, Report No. 322, The Ohio State University, Columbus, 1981.
Rapp, R.H, R.H., “A Summary of the Results from the OSU Analysis of SEASAT Altimeter Data”, Department of Geodetic Science and Surveying, Report No. 335, The Ohio State University, Columbus, 1982a.
Rapp, R.H, R.H., “A Global Atlas of Sea Surface Heights Based on the Adjusted SEASAT Altimeter Data”, Department of Geodetic Science and Surveying, Report No. 333, The Ohio State University, Columbus, 1982b.
Rapp, R.H., “Aspects of Geoid Definition and Determination”, in Proc. of the General Meeting of the IAG, Tokyo, May 1982c.
Rizos, C., “The Role of Gravity Field in Sea Surface Topography Studies”, School of Surveying, Kensington, University of NSW, Sydney, Australia, 1980.
Rowlands, D, D., “The Adjustment of SEASAT Altimeter Data on a Global Basis for Geoid and Sea Surface Height Determination”, Department of Geodetic Science and Surveying, Report No. 325, The Ohio State University, 1982.
Tai, C., and C. Wunsch, “Absolute Measurements of the Dynamic Topography of the Pacific Ocean by Satellite Altimetry”, Nature, Vol$1301, No$15899, pp. 408–420, February 2, 1983.
Tai, C., “On Determining the Large Scale Ocean Circulation from Satellite Altimetry, J. Geophys. Res., 88, 9553–9565, 1983.
Wunsch, C., and V. Zlotnicki, “The Accuracy of Altimeter Surfaces”, paper submitted to the Geophysical Journal, 1984.
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© 1984 Springer Science+Business Media Dordrecht
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Engelis, T., Rapp, R.H. (1984). Global Ocean Circulation Patterns Based on SEASAT Altimeter Data and the GEML2 Gravity Field. In: Seeber, G., Apel, J.R. (eds) Geodetic Features of the Ocean Surface and their Implications. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-1673-4_4
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DOI: https://doi.org/10.1007/978-94-017-1673-4_4
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