Hostname: page-component-7c8c6479df-27gpq Total loading time: 0 Render date: 2024-03-29T11:23:33.398Z Has data issue: false hasContentIssue false

IGS Combined and Contributed Earth Rotation Parameter Solutions

Published online by Cambridge University Press:  12 April 2016

Jan Kouba
Affiliation:
Geodetic Survey of Canada, 615 Booth Street, Ottawa, Ontario K1A 0E9, Canada (e-mail kouba@geod.emr.ca)
Gerhard Beutler
Affiliation:
Astronomical Institute, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland (e-mail beutler@aiub.unibe.ch)
Markus Rothacher
Affiliation:
Astronomical Institute, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland (e-mail beutler@aiub.unibe.ch)

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Since January 1995 the International GPS Service (IGS) has been combining and analyzing daily polar motion (PM) series, produced and submitted by seven IGS analysis centers (ACs) for the IGS Final orbit/clock combinations. Since June 30, 1996 the IGS Earth Rotation Parameter (ERP) series that accompany the IGS combined orbits, also include combined PM rates. Furthermore, since March 1997, the IGS LOD (Length of Day) solutions are based on separate combinations of AC LOD solutions calibrated and weighted according to the IERS Bulletin A definite values. Similar to AC orbit solutions, the PM solutions have improved considerably since 1995, so that currently the IGS combined and the best AC PM solutions are at or below the 0.1 mas precision level, although PM biases may exceed .1 mas. Comparisons of AC ERP and PM rate solutions with the IGS Final combined ERP series revealed signals with 7 and 14-day periods for some AC solutions.

During 1998, the IGS Final and the best AC PM rate solutions compared with Atmospheric Angular Momentum (AAM) at 0.3 mas/day (rms) with an average correlation of about 0.8 and 0.6 for the PM x and PM y rate components. The correlation varied considerably with time and frequency, though significant correlation already started from 6-day periods and reaching maxima within 10 to 50 day period bands. Most of the remaining signal in the PM rate solutions could likely be accounted for by Ocean Angular Momentum (OAM) as seen from the comparisons of combined OAM and AAM with the IGS PM series during 1995 and early 1996 when also OAM data were made available. During this period the IGS PM rates agreed with the combined OAM + AAM series with 0.3 and 0.2 mas/day (rms) for the PM x and y components and with an average correlation of about 0.8 for both PM components.

Type
Part 3. Observational Techniques for Polar Motion
Copyright
Copyright © Astronomical Society of the Pacific 2000

References

Barnes, R.T.H., Hide, R., S., F.R., White, A.A. and Wilson, C.A., 1983, Proc. R. Soc. Lona., Ser. A, 387, pp. 3173.Google Scholar
Beutler, G., Rothacher, M., Springer, T., Kouba, J. and Neilan, R.E., 1998, 32nd COSPAR Scientific Assembly, Nagoya, Japan, Julyl2, in Advances in Space Research (in press).Google Scholar
Beutler, G., 1997, Rotation der Erde: Theorie, Methoden, Resultate aus Satel-litengeodsie und Astrometrie, Astronomisches Institut der Universitt Bern.Google Scholar
Beutler, G., Kouba, J. and Springer, T., 1995, Bull. Geod. 69, pp. 200222.Google Scholar
Boucher, C., Altamimi, Z. and Silliard, P., 1998, IERS Technical Note No. 24, Central Bureau of IERS, Observatory of Paris, France, May.Google Scholar
Chao, F.B. and Gross, R.S., 1995, Geophys. J. Int., 122, 776783.CrossRefGoogle Scholar
Clark, T.A., Ma, C., Ryan, J.W., Chao, B.F., Gipson, J.M., MacMillan, D.S., Vandenberg, N.R., Eubanks, T.M., and Neill, A.E., 1998, EOS, 79, April 28, 205/209.CrossRefGoogle Scholar
Dickey, J.O., Marcus, S.L. Hide, R., Eubanks, T.M. and Boggs, D.H., 1994, J. Geophys. Res., 99, pp 2392123937.CrossRefGoogle Scholar
Eubanks, T.M. Steppe, J.A. and Dickey, J.O., 1988, The Earth’s Rotational and Reference Frames for Geodesy and Geodynamics, pp. 365371.Google Scholar
Herring, T.A. and Dong, D., 1994, J. Geophys. Res., 99, pp 1805118071.Google Scholar
International Earth Rotation Service, 1996, 1995 IERS Annual Report, Observatoire de Paris.Google Scholar
International Earth Rotation Service, 1997, 1996 IERS Annual Report, Observatoire de Paris.Google Scholar
Kołaczek, B., Nuzhdina, M., Nastula, J. and Kosek, W., 1999, IERS Technical Note 26, Observatoire de Paris.Google Scholar
Kouba, J., 1999. IGS 1998 Annual Report, pp.1317.Google Scholar
Kouba, J. 1996, 1996 IGS Analysis Center Workshop Proceedings, Silver Spring, MD, USA, March 19-21, pp. 3342.Google Scholar
Kouba, J. and Mireault, Y., 1996, IGS 1995 Annual Report, pp. 4576.Google Scholar
Kouba, J. and Mireault, Y., 1997, IGS 1996 Annual Report, pp. 55100.Google Scholar
Kouba, J., Mireault, Y., Beutler, G., Springer, T. and Gendt, G., 1998, GPS Solutions, 2, pp. 315.CrossRefGoogle Scholar
Langely, R.B., King, R.E., Shapiro, I.I. Rosen, R.D. and Salstein, D.A., 1981, Nature, Lond. 294, pp. 730732.Google Scholar
Marshall, J., Hill, C., Perelman, L., and Hesley, C.A., 1997, J. Geophys. Res., 102, 57335766.Google Scholar
McCarthy, D.D., 1996, IERS Technical Note 21. Observatoire de Paris.Google Scholar
Mireault, Y., Kouba, J. and Ray, J.R., 1997, EOS Trans. AGU, 78(17), Spring Meeting Suppl., S109.Google Scholar
Mireault, Y., Kouba, J. and Ray, J.R.. 1999, GPS Solutions (in press).Google Scholar
Ponte, R.M. 1997, Geophys., J. Int., I30, 469474.Google Scholar
Ponte, R.M., Stammer, D., Marshall, J., 1998, Nature, 391, Jan. 29, pp. 476479.Google Scholar
Ray, R.D., Steinberg, , Chao, B.F. and Cartwright, D.E., 1994, Science, 264, pp.830832.Google Scholar
Rosen, R.D. and Salstein, D.A., 1985, J. Geoghys. Res., 90, 80338041.Google Scholar
Rosen, R.D. and Salstein, D.A., 1990, J.Geoghys. Res., 95, 265279.Google Scholar
Rosen, R.D. and Salstein, D.A, 1991, Geoghys. Res. Lett., 18, 19251926.Google Scholar
Rothacher, M., Beutler, G., Herring, T.A., Weber, R., 1999, J. Geophys. Res. (in press).Google Scholar
Salstein, D.A. and Rosen, R.D., 1997, 7th Conf. On Climate Variations, American Meteorological Society, Boston, MA, pp. 344348.Google Scholar
Salstein, D.A., Kann, D.M., Miller, A.J. and Rosen, R.D., 1993, Bulletin American Meteorological Society, 71, pp. 6780.Google Scholar
Schaer, S., 1999, PhD Thesis, Astr. Institute of Univ. Berne, Switzerland, March.Google Scholar
Springer, T.A. and Beutler, G., 1993, 1993 IGS Analysis Center Workshop Proceedings, Astr. Institute University of Berne, March 25-26, pp. 242249.Google Scholar