Abstract
An assessment is presented of the probable magnitude of ocean signals causing aliasing in ocean bottom pressure measurements from the GRACE satellite mission. Even after modelling as much of the high frequency signal as possible, variability between 1 mbar (in quiet ocean regions) and 10 mbar (on some shelves) is likely to remain. Interpretation of the resulting retrievals will therefore rely on the facts that the satellite sampling will average the aliasing signal to some extent, and that the spatial patterns of aliased signal and true signal will be different. To this end, a theoretical argument is given, and supported by model diagnostics, suggesting that observable bottom pressure signals will be strongly constrained by the shape of the ocean floor. The modelled magnitudes offer the prospect of significant detectable signals and, while the model accuracy can be called into question, there are hints from Earth rotation and satellite orbit measurements that significant mass redistributions occur in the ocean. It seems certain that we will learn something new about the oceans from GRACE.
Similar content being viewed by others
References
Cox, C. M., and B. F. Chao, 2002: Detection of a large-scale mass redistribution in the terrestrial system since 1998. Science, 297, 831-883 Hide, R., and J. O. Dickey, 1991: Earth's variable rotation. Science, 253, 629–637
Hughes, C. W., and B. A. de Cuevas, 2001: Why western boundary currents in realistic oceans are inviscid: A link between form stress and bottom pressure torques. J. Phys. Oceanogr., 31, 2871-2885
Killworth, P. D., 1995: OCCAM: the Ocean Circulation and Climate Advanced Modelling Project. International WOCE Newsletter., 18, 20-21 (unpublished manuscript).
Wahr J., M. Molenaar, and F. Bryan, 1998: Time variability of the Earth's gravity field: Hydrological and oceanic effects and their possible detection using GRACE. J. Geophys. Res., 103(B12), 30205-30229
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Hughes, C.W., Stepanov, V. Feasibility, and Contribution to Ocean Circulation Studies, of Ocean Bottom Pressure Determination. Space Science Reviews 108, 217–224 (2003). https://doi.org/10.1023/A:1026202705381
Issue Date:
DOI: https://doi.org/10.1023/A:1026202705381