Abstract
ANTARCTIC bottom water (ABW) flows into the Pacific basin from the region between Macquarie Island and Antarctica1ā3. Dynamic considerations suggest that the bottom water flows northwards as an intense current along the western boundary of the Pacific basin4,5. Oceanographers have noted that the Pacific is divided into at least four principal basins which are separated by relatively shallow sills that constrain the flow of water below 4,000 m (refs. 3, 6, 7). The narrow Samoan Passage, first recognized by Reid8, is perhaps the most important channel with depth sufficient to allow a significant flow of bottom water from the southern basin into the central basin. Bottom current velocities in the passage of 5 to 15 cm sā1 towards the north have been measured9 and Nansen casts in the passage revealed a sharp decrease in temperature of 0.27Ā° C in 150 m at a depth of about 4,400 m10. This benthic thermocline marks the abrupt boundary between the deep water and the ABW and supports the observation of cold bottom water flow through the passage. (In a personal communication, P. Lonsdale and J. Reid suggested that the bottom water may include entrained high salinity Atlantic deep water as well as ABW.)
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Deacon, G. E. R., Discovery Report, 15, 1 (1937).
Sverdrup, H. U., Johnson, M. W., and Fleming, R. H., The Oceans, their Physics, Chemistry and General Biology (Prentice-Hall, New York, 1942).
Wooster, W. S., and Volkmann, G. H., J. Geophys. Res., 65, 1239 (1960).
Stommel, H., Deep-Sea Res., 5, 80 (1958).
Craig, H., Chung, Y., and Fiadeiro, M., Earth Planet. Sci. Lett., 16, 50 (1972).
Wust, Georg, Bodentemperatur und Bodenstrom in der Paxifischen Tiefsee (Verlag von E. S. Mittler und Sohn, Berlin, SW68, 1937).
Knauss, J. A., J. Geophys. Res., 67, 3943 (1962).
Reid, J. L., Nature, 221, 848 (1969).
Reid, jun., J. L., Stommel, H., Stroup, E. D., and Warren, B. A., Nature, 217, 937 (1968).
Edmond, J. M., Chung, Y., and Sclater, J. G., J. Geophys. Res., 76, 8089 (1971).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
MACDONALD, K., HOLLISTER, C. Near-bottom Thermocline in the Samoan Passage, West Equatorial Pacific. Nature 243, 461ā462 (1973). https://doi.org/10.1038/243461a0
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1038/243461a0
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.