Wind wave spectrum in high frequency is very important because of its influence on air-sea interaction,and the reflectance properties of sea surface. An effort to estimate the exponent of the equilibrium range in wind wave high frequencyand some other statistical properties, such as the distribution of the significant wave height, the relation between the peak frequency and wind energy and etc., are proceeded by using wave data recorded by a waverider deployed in Suruga Bay from Oct. 22, 1993 to March 18, 1994. The exponent of the equilibrium range is estimated by the least square fit method and is computed in four different frequency ranges. All the expo nents in four different frequency ranges lie in the range from -3.5 and -5.0 and the mean of the exponent in equilibrium range is -4.08, which is consistent with Liu's (1989) results in Great Lake data and the theoretical result of Shen et al. (1993). However,the slope exponent exhibits no variations as wind wave energy increases, which is different with the result of Liu (1989).

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Comparison of CZCS-derived pigment concentration by standard atmospheric correction method with sea-truth data in the waters around Japan shows an underestimate by satellite to a differentdegree. In the range of pigment concentration from 0.2 to 6.0 mg/m3, the CZCSobser vation is lower than in-situ data from about 50% to a factor of 6. Assuming a constant Angstrom exponent during atmospheric correction stage has been found to account for this bias, provided that bio-optical algorithmis valid in those waters. An improved atmospheric correctionmethod which can estimate the Angstromexponent pixel by pixel has been developed based on Gordon ocean color radiance model, and has been evaluated by comparison with these in-situ data. The results demonstrate that this method can increase the accuracy of CZCS-estimated pigment con centration to the level within the system error (30-40%) of CZCS in-water algorithm.

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A one-dimensionalchemical-biological model is constructedto evaluate the capacity of surface watertoabsorbatmospheric carbon dioxide. Themodel variables aretheconcentration of phytoplankton, zooplankton, bacteria, particulate anddissolved non-biological organic material (carbon, nitro gen, andphosphorus), nutrient (PO4, NO3, NH4), total CO2, alkalinity, anddissolved oxygen. The model contains the verticaladvection with the constantupwellingrate and a verticaldiffusion process. Forphytoplankton, processes such as photosynthesis, mortality, extracellular release, sinking andres piration areconsidered. Forzooplankton, grazing, respiration and mortality processes, andforbacte ria theprocesses of uptake of non-biological organic materials, mortality, andrespiration aretakeninto account. Decomposition of non-biological organicmaterials, sinking, nitrification, and exchangeof C02 and 02 with air are also includedin the model. The model is examined for North Pacific surface water (42°N, 175°E) and compared with the observed NOPACCS data (Northwest Pacific Carbon Cycle Study). The result reproduces the obser vation exceptfordissolved oxygen. Theestimated carbon mass balance shows thatmostof the total inorganic carbon utilized forprimary production is supplied within thesurface layers byregeneration as well as from lowerlayer by verticaldiffusive flux. The supplyfrom air to be utilizedfor primary producion is only a few percent, Sensitivity analysis shows that vertical water velocity shouldbe smaller than 10^-6 (cm s^-1), and a verticaldiffusioncoefficientshould be about 1 (cm^2 s^-1) to reproduce observedresults. Amongbiological parameters, the mortality rate of zooplankton and bacteriahave littleeffecton thebiological pump,whilethe formation rateof calciumcarbonate cell affects the result significantly. The limits andproblems of the present one-dimensional model are alsodiscussed.

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Theuptake of anthropogenic CO2 by theocean in the North Pacific is simulated using a threedimensional general circulation model (GCM). Atmospheric pCO2 is prescribed for the period 1800 to 1986 to find the uptake bytheocean. The absorption rate of CO2 into the model ocean in 1986 is 0.7 GtC yr^-1 and the uptake in the simulated period is 37 GtC. Those results do not contradict the previous model and observational studies. The distribution of CO2 in the subpolar region especially in the Bering Sea is affected by the modelrestoring condition of the temperature and salinity to theobserved in the marginal seas, although thetotal amount of CO2 accumulated in themodel ocean is not. Details of thedifference of the distributions of CO2 simulated using the two circulations derived by the GCMs are discussed.

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An information onocean surface wind speed in remote-sensed image is required for accurate application of atmospheric correction algorithm for ocean color remote sensor. A method for retrieval of surface wind speed with Sun glitter intensity in visible range is proposed with theaid of probability distribution of wave facet which varies with change in wind speed. The retrieval accuracy is estimated with the error in the retrieval of wind speed, water-leaving radiance and phytoplankton pigment concentration obtained by atmospheric correction using retrieval wind speed in a model atmosphere-ocean system. This method is applied to ground, vessel and air borne radiance data and the result showed the successive correlation between retrieved wind speed and observed one.

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A correlation function varying in both time and space, ”Time-Space Correlation method”, was applied to GEOSATaltimeter data collected from November 1986 to September 1989 (repeat cycles 1- 62) in order to estimate wave propagation of theeddy field in the Kuroshio Extension region. Analysis of 62 sets of collinear data has yielded the dominant speeds and directions of wave propagations. In the zonaldirection, waves tend to propagate westward with speeds of 1.5 - 5.6 cms^-1 between 40°N and 30°N, which are in good agreement with the theoretical speeds. In the meridional direction, the tendency of wave propagation in the eastern region of the study area is different from that in the western region. In the eastern region, waves seem to propagate northwardwith speeds of 2.0 - 3.0 cms^-1. However, we cannot determine whether these north ward speeds are actual speeds or apparent speeds due to decrease of the zonal speeds with in creasinglatitude. In contrast,propagations in the western regiontend to be towardthe axis of the Kuroshio Extension, which is consistent with the Kuroshio Extension being an energy source.

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It is possible to elucidatea lot of chemical, physical and biological phenomena in the oceanby obtaining the high quality and reproducibility nutrient concentration data sets. Therefore, we need conferences to talk about calibrating and getting the common standards, replicating samples, settingup the reference stations, correcting the sample concentrations, plotting the ver tical profiles and so on. From now on, these checks for completeness of correction are necessary. After that proceeding mentioned above, we would be able to get and accumulate the excellent data sets globally.

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Some resent works in Japan on the standardization of the measurement of total carbonate (TCO2) arereviewed. Themeasurement method and thestandard areneeded to setconsistent and traceable among each labs to keep uncertainties of the data within few μmol/kg in worldwide scale. A experimental work to make a standard of total carbonate based on natural sea water is introduced. The results of the time series measurement improves that the sea water standard keeps its concentration ofTCO2 over 80 days with the variability of ± 1.4 μ mol/kg. Some ex amples of the intercalibration works in Japanese labs show that there are complex and unique systematic offsets between each lab’s data. Thus it is recommended that a consistent program of the intercalibaration study for total carbonate is needed to put forward.

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