A total of 293 measurements of respiration rate were made on planktoniccrustaceans collected in different seasons from the Inland Sea of Japan. Therelationship between the rate of oxygen consumption (R, μl O₂ indiv.^-1 hr^-1) andbody dry weight (W, mg indiv.^-1), as expressed by a power function (R=aW^b, or log
R=log a+b log W), was established as a function of temperature (T, °C).The slope of the regression equation (b) was not significantly affected by seasonaltemperature variation, but the intercept of the equation (log a) was strongly influencedby temperature. The equation describing this general relation is log R=(0.0444T-0.333) + 0.713 log W.

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A simple statistical method based on arithmetic mean and correspondingvariance is proposed for analysis of a time series of NOAA-8 satellite Advanced Very High Resolution Radiometer (AVHRR) images. We focused on the characteristicsof temporal and spatial variabilities of sea surface temperature depending onmesh sizes used for the statistics. By applying this method to several images ofthe south Japan Sea in spring of 1984, we could clarify some natures of eddieswhich cannot be recognized only by one image. They include life time and spatialscale of eddies.

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In recent years, anomalous southward intrusions of the Oyashio havebeen observed frequently from winter to late spring. A barotropic model is usedto see the occurrence of the Oyashio intrusion, with special reference to a shorttime lag between the change in the wind stress in midwinter and the occurrenceof the Oyashio intrusion generally in spring of the same year. It is shown thatthe barotropic response of the ocean to the change in wind stress is fast, and itsrepresentative time scale is about 50 days at most. The southward shift of the Oyashio and the subarctic circulation are simulated quantitatively, when the imposedwind stress is changed from the mean wind stress prior to no Oyashio intrusion tothat prior to the Oyashio intrusion. It is suggested that the southward intrusionof the Oyashio is a phenomenon connected with the global change in atmosphericcirculation.

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Relationships of the sea level differences between Naze and Nishinoomote and between Kushimoto and Uragami with wind stress over the North Pacific are examined for interannual variability. These sea level differences areconsidered to be indications of Kuroshio transport in Tokara Strait and Kuroshiopath south of Enshu-nada. respectively.
In the sea level difference between Kushimoto and Uragami, dominant variationsare found to have periods of about seven years and 3-4 years. The variation ofabout 7-year period, which corresponds to that in the Kuroshio path between thelarge meander and non-large meander, is coherent with the variation of the windstress curl in a region about 2, 400km east of the Kii Peninsula, where negativestress curl weakens about two years before the sea level difference drops (i.e. thelarge meander path in the Kuroshio generates). The variation of the 3-4 yearperiod is coherent with that of the wind stress in a large area covering the easternequatorial Pacific, which suggests that it links with global-scale atmospheric variations.
Interannual variation in sea level difference between Naze and Nishinoomoteis not coherent with that between Kushimoto and Uragami, which suggests that itis not related to the variation of the Kuroshio path south of Enshu-nada, but iscoherent with that of the zonally-integrated Sverdrup transport in the latitudinalzone along 30KN. It is suggested that the interannual variation of the Kuroshiotransport in Tokara Strait can be explained by the barotropic response to the windstress.

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The barotropic instability of a boundary jet on a beta plane is consideredwith emphasis on the effect of internal viscosity. An eigenvalue problem for thedisturbance equations and its inviscid version are solved by the aid of numericalmethods, and instability characteristics are determined as functions of the Reynoldsnumber R for various values of the beta-parameter. Typical disturbance structures (eigenfunctions) are also computed.
Numerical examples show that the minimum critical Reynolds number R_cr forinstability is smaller than 100. At a Reynolds number of the order of hundreds, there appears a second mode of instability in addition to the first unstable modeoriginating at R_cr; a kind of ‘resonance’ between the first and second eigenvaluesoccurs at the particular value of R. The neutral stability curves are accordinglymulti-looped. Although each of the two unstable modes asymptotically approachesits inviscid counterpart as R→∞, the asymptotic approach to the inviscid limit israther slow and the effect of varying R is conspicuous even at R-O (10⁴). It isthus demonstrated that the Reynolds number is an essential stability parameter forreal boundary jets.

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It is a great honour to be awarded the Oceanographical Society of Japan Prize for 1988 and to be provided with this opportunity to review our work ontrophic relations in the pelagic environment of the sea.Many Japanese colleagueshave participated in Canada on our experiments.These persons include Drs.H.Seki, M. Takahashi, A. Hattori, T. Ikeda, I. Koike, M. Ohtsu, S. Ichimura, K.Iseki, E. Matsumoto, N. Handa, Y. Maita, and others without whom our workon marine ecosystems would have assumed much less importance.In addition, thevisit of Professor M.Uda to Nanaimo in 1959, and his lectures on fisheries oceanography, have always been an inspiration to me in the practical application ofoceanography.
For me, work on trophodynamic relationships grew out of my early associationwith Dr. J. D. H. Strickland who initiated some ecosystem studies using large plasticbags in the 1960s (Strickland and Terhune, 1961;Strickland, 1967).The CEPEXprogram (e.g.Parsons, 1978), which was started about a decade later, gave us thefirst real opportunity to break away from laboratory studies, where only specieswhich generally grew best were studied, and to perform studies under near naturalconditions on multiorganism communities.The purpose of this program was toprovide some answers to practical problems as well as to gain a fundamental understandingof biological oceanographic processes.This program was started at a timewhen a large number of stories were circulating (e.g.Heyerdahl, 1975) that manwas about to kill life in the oceans through pollution.In a practical sense whatI believe that the CEPEX program showed was that the oceans were much moreresilient than had been supposed.The effect of many kinds of pollutants testedduring this program was to change the course of ecosystem interactions but not tocause the elimination of life.The scientific value of these experiments went muchfurther in giving us time series data about how the physical/chemical environmentinteracts with different trophic levels.For the first time, the biological oceanographerwas liberated from the hopeless entanglement of time and space in thesea, and it was now possible to follow population dynamics of planktonic organisms (Mullin, 1982).

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