CTOH corrections (binary format)

Up-to-date algorithms and corrections added in a homogeneous way to all CTOH MGDR data bases

Additional corrections included in CTOH standard extraction products :

Parameter Name scale factor (unity: meter)
Purpose and References
Latest ocean tide correction from the FES2004 hydrodynamic model developed at LEGOS, Toulouse, France.
REF.: LETTELIER, T., F. LYARD, F. LEFEBRE (2004). The new global tidal solution : FES2004. Jason SWT Meeting Abstracts, St Petersburg, Florida, Nov.2004.
10-3 Ocean tide correction from the GOT2000 tidal model developed at GSFC.
10-3 REF.: Tide Predictions in Shelf and Coastal Waters: Status and Prospects. Ray R. D., Egbert G. D., Erofeeva S. Y. in, Coastal Altimetry, Ed. Vignudelli S., Kostianoy A., Cipollini P., Benveniste J., Springer.
10-5 Inverted barometer effect calculated from 6-hourly ECMWF surface pressure data and referenced to the global mean surface pressure over the oceans and sea-ice. Improvement to the IB response calculated by AVISO for TOPEX which is relative to a constant 1013 mbar reference surface. The new version conserves mass over the ocean.
ib_ECMWF_bf 10-5 ib_ECMWF_NF for periods greater than 20 days.
10-5 High-frequency barotropic ocean response to ECMWF wind and surface pressure forcing, calculated using the MOG2D barotropic model. Incluon-isostatic ocean response to surface forcing. This correction replaces the standard inverse barometer correction or ib_ECMWF.
REF.: CARRERE L., LYARD F. (2003) Modeling the barotropic response of the global ocean to atmospheric wind and pressure forcing - comparisons with observations. Geophysical Res. Lett. vol. 30, n. 6,1275, doi:10:1029/2002GL016473.
ib_MOG2D_hf 10-5 ib_MOG2D_NF for periods smaller than 20 days.
(Biais_emnp) 10-3
Non-parametric versions of the EM bias for Topex/Poseidon and Jason.
wet_tropo_cls 10-3
Wet troposphere correction calculated by CLS over the continents using NCEP data      Wet troposphere correction over the continents isct altitude, interpolated from the gridded NCEP levels.
REF.: MERCIER (2003), Satellite altimetry over non ocean areas : an improved wet tropospheric correction from meteorological models, Joint EGS-AGU meeting, Nice, Spring 2003.
geoid_grace 10-3
Marine geoid GGM02C from the GRACE mission    GGM02C - uses GRACE data up to degree 200 - and is constrained with terrestrial gravity information for the higher orders (shorter wavelengths).
WEB: http://www.csr.utexas.edu/grace/gravity/ggm02/oceanographic_sciences.html.
- Tapley B, Ries J, Bettadpur S, Chambers D, ChengM, Condi F, Gunter B, Kang Z, Nagel P, Pastor R, Pekker T, Poole S, Wang F (2005) GGM02: an improved Earth gravity field model from GRACE. J Geod 79:467-96478. doi:10.1007/s00190-005-0480-z.
- BIROL, F., J. M. BRANKART, J. M. LEMOINE, P. BRASSEUR, J. VERRON, Assimilation of satellite altimetry referenced to the new GRACE geoid estimate. Geophys. Res. Lett., VOL. 32, L06601, doi:10.1029/2004GL021329, 2005
gim_ku, gim_s
WEB: http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VHB-3YDGC8J-2&_user=3521029&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1112320696&_rerunOrigin=google&_acct=C000028798&_version=1&_urlVersion=0&_userid=3521029&md5=92792ec78673d3ec59fc071750194414#bbib8
REF.: B.A., Harris, I.L., Ho, C.M., Lindqwister, U.J., Mannucci, A.J., Pi, X., Reyes, M.J., Sparks, L.C., Wilson, B.D.,(1999). Automated daily process for global ionospheric total electron content maps and satellite ocean altimeter ionospheric calibration based on Global Positioning System data Journal of Atmospheric and Solar-Terrestrial Physics 61 1205-1218
The Non-parametric sea-state bias from CLS is calculated from a table based on SWH and sigma-0 values, a separate table of values exists for each altimeter : Topex-A, Topex-B, Jason-1, GFO and ENVISAT. Jason-2 data is calculated from the Jason-1 table. Use the BM4 formula for Poseidon. References for the different tables are given on the AVISO web site : http://www.aviso.oceanobs.com
- LABROUE, S., GASPAR, P., DORANDEAU, J., ZANIFE, O.Z., MERTZ, F., VINCENT, P., CHOQUET, D., (2004). Nonparametric estimates of the sea state bias for the Jason-1 radar altimeter, Marine Geodesy, 27, 453-481, 2004.
- LABROUE, S., GASPAR, P., (2002). Comparison of nonparametric estimates of the TOPEX A, TOPEX B, and Jason-1 sea state biases. Jason SWT Meeting Abstracts, New Orleans, Oct. 2002.
- LABROUE, S., DORANDEAU, J., (2003). Nonparametric estimation of the GFO sea state bias, Tech. Report, CLS-DOS-NT-03.847, CLS, Ramonville, France.
- Labroue, S., P. Gaspar, J. Dorandeu, F. Mertz, OZ. Zanifé, 2006, Overview of the Improvements Made on the Empirical Determination of the Sea State Bias Correction <http://earth.esa.int/workshops/venice06/participants/318/paper_318_labroue.pdf>, 15 years of progress in radar altimetry Symposium, Venice, Italy, 2006.
The Dual-frequency ionospheric correction is noisy, and is smoothed with a 20 point median filter, adapted with variable length approaching the coasts to maintain maximum data coverage. Small gaps (< 5 points) are linearly interpolated..
(topex: Haut_mss)
CLS Mean sea surface MSSO1, based on Geosat, ERS and Topex/Poseidon data 1985-1999.   Improvement on the mean sea surface distributed by AVISO, with data until 1993.
WEB: http://www.aviso.oceanobs.com/en/data/products/

Document Actions

logo cnes logo IRD Logo université de Toulouse Logo université Paul Sabatier Logo CNRS
Logo bibliothèque OBS Logo Observatoire Midi Pyrénées