Seasonal variation of CO_2 fluxes over the Sea of Japan

众所周知，大气中的CO_2含量正在增加。CO_2浓度增加的主要原因是化石燃料的燃烧和陆地利用的变化，而海洋被认为是人类活动产生的CO_2的主要汇。这意味着，准确测量海-气界面上的CO_2交换速率是深入了解CO_2-全球气候动力学的关键。最有前途的湍流通量测量技术是涡旋相关技术。然而，在考察船或浮标上进行涡旋相关测量的困难是众所周知的。当测量平台为科考船时，海气界面的CO_2通量通常采用体积法估算。然而，用散装技术计算的CO2通量受许多因素的影响，如水温、盐度和海水中的生物生产力，以及大气中的风速和稳定性条件。许多…上述未知参数更多地包含在传递系数中，因为主体技术是原始的，它涉及到从大气和海水中的CO_2分压和总体传递速度三个参数计算CoQ通量。我们计划研究气象技术，如空气动力学、光谱密度和涡旋相关技术，以测量海洋上的CO_2通量。为此，自2000年以来的夏季，在日本海的京都大学绪方波观测站精心设计的码头上进行了观测。涡旋相关法、空气动力学法和谱密度法确定的湍流通量在海风条件下符合得很好。空气动力学和频谱密度技术不需要明确测量垂直风速。这是通量测量技术与从考察船或浮标上获得的数据一起使用时的基本特点。这也促使我们得出结论，空气动力学和谱密度技术适合用来代替散体技术。较少

It is well known that CO_2 content of the atmosphere is increasing. The source of this increasing CO_2 has been assumed to be the combustion of fossil fuels and land use change, and the ocean has been considered as a major sink for anthropogenically produced CO_2. This implies that the accurate measurement of CO_2 exchange rates across the air-sea interface is the key to achieving a deeper understanding of the CO_2-global climate dynamics. The most promising technique for turbulent flux measurements is the eddy correlation technique. However, the difficulties of the eddy correlation measurements on research vessels or buoys are well recognized. The CO_2 flux across the air-sea interface is usually estimated by the bulk technique when the measuring platform is a research vessel. CO_2 fluxes by the bulk technique, however, are affected by many factors such as water temperature, salinity and bio-productivity in the seawater, and wind speed and stability conditions in the atmosphere. Many … More of the unknown parameters mentioned above are subsumed within the transfer coefficient, because the bulk technique is the primitive one which involves the calculation of COQ fluxes from three parameters, the partial pressure of CO_2 in the atmosphere and in the seawater, and the bulk transfer velocity. We planned the project to investigate meteorological techniques such as aerodynamic, spectral density, and eddy correlation techniques to measure, CO_2 fluxes over the ocean. For this purpose, observations were curried out during the summer season since 2000 on a well-designed pier of the Ogata Wave Observatory, Kyoto University in the Sea of Japan. Turbulent fluxes determined by the eddy correlation, aerodynamic and spectral density techniques agree well under sea breeze conditions. The aerodynamic and spectral density techniques do not require explicit measurements of vertical wind velocity. This is the essential feature of the flux measurement technique as regards its use with data obtained on research vessels or buoys. This also encourages us to conclude that the aerodynamic and spectral density techniques are suitable to be used in place of the bulk technique. Less