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。二氧化碳增加的来源被认为是化石燃料的燃烧和土地利用的变化，海洋被认为是人为产生的二氧化碳的主要汇。这意味着准确测量海气界面上的co2交换速率是深入了解co2 -全球气候动力学的关键。涡流相关技术是最有前途的湍流通量测量技术。然而，在研究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，通常采用体积法估算海气界面上的CO_2通量。然而，散装技术的CO_2通量受海水水温、盐度和生物生产力以及大气风速和稳定条件等多种因素的影响。由于体积法是一种原始的方法，它只从大气和海水中CO_2的分压和体积传递速度三个参数来计算COQ通量，因此上述许多未知参数都包含在传递系数中。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，以测量海洋上的二氧化碳通量。为此，自2000年夏季以来，在日本海京都大学绪方波浪观测站的一个精心设计的码头上进行了观测。在海风条件下，涡旋相关、气动和谱密度技术测定的湍流通量吻合较好。空气动力学和谱密度技术不需要明确测量垂直风速。这是通量测量技术在使用研究船或浮标上获得的数据方面的基本特点。这也促使我们得出结论，空气动力学和谱密度技术适合用于代替体技术。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