Abstract
Synoptic ship and satellite observations were performed of the Kuroshio warm-core ring (KWCR) 93A and its adjacent waters, off Sanriku, northwestern North Pacific, between early April and late June 1997. The temporal and spatial distribution of chlorophylla (Chl-a) and sea surface temperature in the study area were analyzed using data from ADEOS Ocean Color and Temperature Scanner (OCTS) and NOAA Advanced Very High Resolution Radiometer (AVHRR). The objective of this study was to describe the temporal and spatial variability of the spring bloom and understand its relationship with the changes in the hydrographic structure of these waters in and around KWCR 93A. The maximum value of Chl-a concentration in the ring was less than 1 mg/m3 during April. The spring bloom in the ring occurred early in May and the relatively high maximum (>1.0 mg/m3) continued from early in May to mid-June. In late June, a ship-observed surface Chl-a concentration of less than 0.4 mg/m3 suggests that the spring bloom had already declined in and around KWCR 93A. Double spiral structures of warm and cold streamers appeared from late April to mid-May, which may have an influence on the occurrence of the spring bloom in and around the ring. In this episodic event, the warm streamer can maintain the available potential energy of the ring and the strength of upwelling around the ring. The cold streamer provided water with a high Chl-a concentration to the surface layer of the ring. In order to understand the temporal and spatial variability of Chl-a distribution in the ring, the behavior of the warm and cold streamers needs to be taken into consideration.
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References
Evans, R. H., K. S. Baker, O. B. Brown and R. C. Smith (1985): Chronology of warm-core ring 82B.J. Geophys. Res.,90(C5), 8803–8811.
Faculty of Fisheries, Hokkaido University (1998): Data record of oceanographic observations and exploratory fishing, No. 41, p. 328.
Gordon, H. R., D. K. Clark, J. W. Brown, O. B. Brown and R. H. Evans (1982): Satellite measurement of the phytoplankton pigment concentration in the surface waters of a warm core Gulf Stream ring.J. Mar. Res.,40, 491–502.
Hata, K. (1974): Behavior of a warm eddy detached from the Kuroshio.J. Meteorol. Res.,26, 295–321 (in Japanese with English abstract).
Hooker, S. B. and W. E. Esaias (1993): An overview of the SeaWiFS Project.Eos, Transactions, American Geophysical Union,74, 245–246.
Inagake, D. (1997): Statistics of the Kuroshio warm-core ring migration by historical data from 1981 to 1996.Bull. Tohoku Natl. Fish. Res. Inst.,59, 149–162 (in Japanese with English abstract).
Inagake, D. and S. Saitoh (1998): Description of the oceanographic condition off Sanriku, Northwestern Pacific, and its relation to spring bloom detected by Ocean Color and Temperature Scanner (OCTS) images.J. Oceanogr.,54, this volume, 479–494.
Kasai, H., H. Saito, A. Yoshimori and S. Taguchi (1997): Variability in timing and magnitude of spring bloom in the Oyashio region, the western subarctic Pacific off Hokkaido, Japan.Fish. Oceanogr.,6, 118–129.
Kawai, H. (1972): Hydrography of the Kuroshio Extension. p. 235–352. InKuroshio: Its Physical Aspects, ed. by H. Stommel and K. Yoshida, University of Tokyo Press.
Kawai, H. and S. Saitoh (1986): Secondary fronts, warm tongues and warm streamers of the Kuroshio Extension system.Deep-Sea Res.,33, 1487–1507.
Kawamura, H., K. Mizuno and Y. Toba (1986): Formation process of a warm-core rings in the Kuroshio-Oyashio frontal zone—December 1981–October 1982.Deep-Sea Res.,33, 1617–1640.
Kishi, M. J. (1994): Prediction of phytoplankton growth in a warm-core ring using three dimensional ecosystem model.J. Oceanogr.,50, 489–498.
Kitano, K. (1975): Some properties of the warm eddies generated in the confluence zone of the Kuroshio and the Oyashio currents.J. Phys. Oceanogr.,5, 245–252.
Okada, Y. and Y. Sugimori (1986): Decay of warm-core rings based on observation of available potential energy.Deep-Sea Res.,33, 1577–1599.
Parsons, T. R., Y. Maita and C. M. Lalli (1984):A Manual of Chemical and Biological Methods for Seawater Analysis. Pergamon Press, Oxford, 173 pp.
Saino, T., S. Shang, Y. Mino, K. Suzuki, H. Nomura, S. Saitoh, H. Miyake, T. Masuzawa and K. Harada (1998): Short term variability of particle fluxes and its relation to variability in sea surface temperature and chlorophylla field detected by Ocean Color and Temperature Scanner (OCTS) off Sanriku, northwestern North Pacific in the spring of 1997.J. Oceanogr.,54, this volume, 583–592.
Saitoh, S. (1995a): OCTS on ADEOS. p. 473–480. InOceanographic Application of Remote Sensing, ed. by M. Ikeda and F. W. Dobson, CRC Press, Boca Raton.
Saitoh, S. (1995b): AVHRR on NOAA, p. 407–417. InOceanographic Application of Remote Sensing, ed. by M. Ikeda and F. W. Dobson, CRC Press, Boca Raton.
Saitoh, S., I. Asanuma, Y. Sasaki and K. Muneyama (1984): Satellite observation of temperature and ocean color distribution in the surface waters of a Kuroshio warm core ring.La mer,22, 163–166.
Saitoh, S., S. Kosaka and J. Iisaka (1986): Satellite infrared observations of Kuroshio warm-core rings and their application to study of Pacific saury migration.Deep-Sea Res.,33, 1601–1615.
SeaSpace (1995): TeraScan 2.6 Reference Manual. Volume 1 & 2.
Shimada, M., H. Oaku, Y. Mitomi, H. Murakami, A. Mukaida, Y. Nakamura, J. Ishizaka, H. Kawamura, T. Tanaka, M. Kishino and H. Fukushima (1998): Calibration and validation of the ocean color version-3 product from ADEOS OCTS.J. Oceanogr.,54, this volume, 401–416.
Shiomoto, A., K. Sasaki and T. Shimada (1996): Primary production and contribution of “new” production in the warm-core ring and the cold streamer off Sanriku in May 1990.La mer,34, 1–9.
Sugimoto, T. and H. Tameishi (1992): Warm-core rings, streamers, and their role on the fishing ground formation around Japan.Deep-Sea Res.,39 (Suppl. 1), S183-S201.
Sugimoto, T., Y. Kawasaki and J. Li (1992): A description of the time-dependent hydrographic structure of the warm streamer around the Kuroshio warm-core ring 86B.Deep-Sea Res.,39 (Suppl. 1), S77-S96.
Terazaki, M. (1992): Horizontal and vertical distribution of chaetognaths in a Kuroshio warm-core ring.Deep-Sea Res.,39 (Suppl. 1), S231-S245.
Tomosada, A. (1986): Generation and decay of Kuroshio warmcore rings.Deep-Sea Res.,33, 1475–1486.
Tranter, D. J., R. R. Parker and G. R. Cresswell (1980): Are warmcore eddies unproductive?Nature,284, 540–542.
Tsuda, A. and T. Nemoto (1992): Distribution and growth of salps in a Kuroshio warm-core ring during summer 1987.Deep-Sea Res.,39 (Suppl. 1), S219-S229.
Yasuda, I., K. Okuda and M. Hirai (1992): Evolution of a Kuroshio warm-core ring—variability of the hydrographic structure.Deep-Sea Res.,39 (Suppl. 1), S131-S161.
Yentsch, C. S. and D. A. Phinney (1985): Rotary motions and convection as a means of regulating primary production in warm core rings.J. Geophys. Res.,90(C2), 3237–3248.
Yokouchi, K., D. Inagake, Y. Matsuo and M. Murakami (1993): Hydrographic structure and chlorophylla distributions observed during southward movement of a Kuroshio warm-core ring into subtropical waters.Bull. Tohoku Natl. Fish. Res. Inst.,55, 75–88 (in Japanese with English abstract).
Yoshimori, A. and M. J. Kishi (1994): Effects of interaction between two warm-core rings on phytoplankton distribution.Deep-Sea Res.,41, 1039–1052.
Yoshimori, A., J. Ishizaka, T. Kono, H. Kasai, H. Saito, M. J. Kishi and T. Taguchi (1995): Modeling of spring bloom in the western subarctic Pacific (off Japan) with observed vertical density structure.J. Oceanogr.,51, 471–488.
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Saitoh, SI., Inagake, D., Sasaoka, K. et al. Satellite and ship observations of Kuroshio warm-core ring 93A off Sanriku, northwestern North Pacific, in spring 1997. J Oceanogr 54, 495–508 (1998). https://doi.org/10.1007/BF02742451
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DOI: https://doi.org/10.1007/BF02742451