nerc.ac.uk

Three forms of variability in Argentine Basin ocean bottom pressure

Hughes, C. W.; Stepanov, V. N.; Fu, L-L.; Barnier, B.; Hargreaves, G. W.. 2007 Three forms of variability in Argentine Basin ocean bottom pressure. Journal of Geophysical Research, 112 (C1), C01011. 10.1029/2006JC003679

Full text not available from this repository. (Request a copy)

Abstract/Summary

Ocean bottom pressure data are examined from a year-long deployment of two bottom pressure recorders, separated by 417 km, in the Argentine Basin. Three forms of variability are found. At high frequencies ( periods shorter than 2 hours) the signal appears to be due to gravity wave propagation with the waves preferentially coming from the west. At intermediate frequencies ( periods between 2 hours and 12 days), the two records are highly coherent and in phase, reflecting large-scale coherent fluctuations which are well reproduced in a barotropic ocean model. However, the dominant mode is at a period of 20 days, with a phase lag of about 90 - 100 degrees between the two records, consistent with the a mode of variability previously inferred from satellite altimetry and current meters, although the slightly shorter period is consistent with the suggestion that more than one mode contributes to the altimeter observations. Comparison with altimetry demonstrates that aliasing of higher-frequency signals is not a significant source of error and confirms that a previously used altimetry mapping technique reduces the apparent amplitude of the mode. The pressure records show a transport change of about 280 Sv over one 12-day period, and altimetry suggests that regions of higher variability exist. The mode is only weakly excited in barotropic models but is strongly excited in a baroclinic model with a realistic eddy field, suggesting that it is intrinsically linked to interactions between eddies, mean flow, and topography

Item Type: Publication - Article
Digital Object Identifier (DOI): 10.1029/2006JC003679
Programmes: Oceans 2025 > Climate, ocean circulation and sea level
ISSN: 0148-0227
Additional Information. Not used in RCUK Gateway to Research.: Barnier, B. LEGI, Grenoble, France, Fu, L-L. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA
Additional Keywords: ISI LLT32 THEME 1 PROG1 REF NISCJAN07 OPM2007 AR0607 AJWJAN07 HIJ JOURNAL OVERSEAS CO-AUTHORS LARGE SCALE OSCILLATIONS SEA LEVEL VARIABILITY TOPEX/POSEIDON CIRCULATION RESONANCE ATLANTIC OCEAN DYNAMICS WAVES
NORA Subject Terms: Marine Sciences
Date made live: 08 Oct 2008 11:28
URI: http://nora.nerc.ac.uk/id/eprint/2663

Actions (login required)

View Item View Item