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The advance and retreat of the thermocline on the continental shelf

Published online by Cambridge University Press:  11 May 2009

R. D. Pingree
R. D. Pingree*
Affiliation:
Institute of Oceanographic Sciences, Wormley, Surrey
*
* Present address: The Laboratory, Marine Biological Association, Citadel Hill, Plymouth.
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Extract

An important factor in the seasonal cycle of phytoplankton growth is the establishment and breakdown of the seasonal thermocline (Sverdrup, Johnson & Fleming, 1946). When surface heating is sufficient, more buoyancy is produced than can be dissipated by wind and tide. The stabilization of the water column allows the phytoplankton sufficient time in the surface layer to utilize the light energy for increased net production and the spring bloom is triggered. At the end of the summer period the erosion of the thermocline may result in an increase of nutrients in the upper layers. If production has become limited by surface depletion of nutrients during the summer, then the thermocline breakdown may result in an autumnal bloom particularly if a period of calm sunny weather follows. The importance of the thermocline development and season length is clearly illustrated in plankton studies of the North Atlantic, for example Robinson (1970).

Type
Research Article
Information
Journal of the Marine Biological Association of the United Kingdom , Volume 55 , Issue 4 , November 1975 , pp. 965 - 974
Copyright
Copyright © Marine Biological Association of the United Kingdom 1975

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References

Armstrong, F. A. J., Butler, E. I. & Boalch, G. T., 1974. Hydrographic and Nutrient Chemistry surveys in the Western English Channel during 1965 and 1966. Journal of the Marine Biological Association of the United Kingdom, 54, 895–914.Google Scholar
Bowden, K. F., 1948. The processes of heating and cooling in a section of the Irish Sea. Monthly Notices of the Royal Astronomical Society. Geophysical Supplement, 5(7), 270–81.Google Scholar
Cooper, L. H. N., 1960. The water flow into the English Channel from the South-west. Journal of the Marine Biological Association of the United Kingdom, 39, 173–208.CrossRefGoogle Scholar
Dietrich, G., 1951. Influences of tidal streams on oceanographic and climatic conditions in the sea as exemplified by the English Channel. Nature, London, 1968, 8.CrossRefGoogle Scholar
Fearnhead, P. G., 1975. On the formation of fronts by tidal mixing around the British Isles. Deep Sea Research 22, 311–21.Google Scholar
Grall, J. R., Le Fevre-Lehoerff, G. & Le Fevre, J., 1971. Observations sur la distribution du plancton à proximité d'Ouessant en Juin 1969 et ses relations avec le milieu physique. Cahiers oceanographiques, 23, 145–70.Google Scholar
Matthews, D. J., 1911. Report on the physical conditions in the English Channel and adjacent waters 1906, with a note on mean conditions for 1903–9. Report of the North Sea Fisheries Investigations Committee, 269–82.Google Scholar
Pingree, R. D., Forster, G. R. & Morrison, G. K., 1974. Turbulent convergent tidal fronts. Journal of the Marine Biological Association of the United Kingdom, 54, 469–79.CrossRefGoogle Scholar
Pingree, R. D. & Pennycuick, L., 1975. Transfer of heat, fresh water and nutrients through the seasonal thermocline. Journal of the Marine Biological Association of the United Kingdom, 55, 261–74.CrossRefGoogle Scholar
Robinson, G. A., 1970. Continuous plankton records: Variations in the seasonal cycle of phytoplankton in the North Atlantic. Bulletins of Marine Ecology, 6, 333–45.Google Scholar
Sager, G. & Sammler, R., 1968. Atlas der Gezeitenstrome für die Nordseey den kanal unddie Irische See. 1–58 pp. Rostock: Seehydrographischer Dienst der DDR.Google Scholar
Simpson, J. H. & Hunter, J. R., 1974. Fronts in the Irish Sea. Nature, London, 1250, 404–6.CrossRefGoogle Scholar
Southward, A. J., 1962. The distribution of some plankton animals in the English Channel and approaches. II. Surveys with the Gulf III high-speed sampler, 1958–60. Journal of the Marine Biological Association of the United Kingdom, 43, 275–375.CrossRefGoogle Scholar
Sverdrup, H. U., Johnson, M. W. & Fleming, R. H., 1946. The oceans their physics, chemistry and general biology. 1087 pp. New York: Prentice-Hall.Google Scholar