Study on actual behavior of mesoscale eddies in oceanic turbulence with satellite-image analysis and numerical simulation

Ocean currents such as the Kuroshio and Oyashio, which strongly influence on the flow fields around Japan-Island-Chain, are characterized by the mesoscale eddies with the representative horizontal length scale of a few hundreds kilometers. Although the behaviors of the mesoscale eddies are closely related with the coastal environments, there are a number of unknown factors for the dynamical evolution of the mesoscale eddies. On the other hand, the head investigator in this project has been monitoring the large-scale patterns of the water temperature and velocity vectors on sea surfaces with the image processing for the polar orbiting meteorological satellite NOAA, and then attempted to examine ocean current structures and the actual motion of mesoscale eddies around Japan-Island-Chain. For further evolutions of the above study, in the present project, we investigate the actual behavior of mesoscale eddies in the flow fields around Japan-Island-Chain. Furthermore we try to develop the n … More umerical method of ocean current including the mesoscale eddies. The main results of the project are expressed in the followings.(1)Measurements for oceanic turbulence with the satellite-image analysisWe have conducted flow visualizations and sea-surface velocity measurements with NOAA/AVHRR thermal infrared data. Every day the monitoring of the oceanic turbulence has been continuously performed by capturing the satellite data. Combing the above satellite-based data and other published data concerning the oceanic turbulence, we have constructed the database for the oceanic turbulence around Japan-Island-Chain.(2)Ocean current simulations with a new nesting approachTo effectively incorporate the above measured ocean-current data on ocean current simulations, a new nesting procedure for ocean current model was developed and then applied to the ocean current simulation. Through the comparison of the computed and observed results, we have confirmed the fundamental validity of the present method. Less

海洋电流（例如黑果岛和奥亚西奥）对日本 - 岛链周围的流场的强烈影响，其特征是中尺度的涡流，其代表性水平长度尺度为几百公里。尽管中尺度涡流的行为与沿海环境密切相关，但中尺度涡流的动态演变有许多未知因素。另一方面，该项目中的首席调查员一直在监视海面上水温和速度向量的大规模模式，并进行了图像处理，用于对极性轨道的气象卫星NOAA进行处理，然后试图检查海洋电流结构以及日本 - 伊斯兰省 - 伊斯兰省 - 芝士chain的实际运动。对于上述研究的进一步发展，在本项目中，我们研究了日本链链周围流动场中中尺度涡流的实际行为。开发N…更刺激的海洋流动方法，包括中尺度涡流。 （1）通过卫星图像分析测量了海洋湍流的测量值，我们已经进行了流动可视化和使用NOAA/AVHRR热红外数据进行的流动可视化和海面速度测量。每天通过捕获卫星数据来不断执行海洋湍流的监测。梳理上述基于卫星的数据和其他有关海洋湍流的数据，我们已经构建了日本 - 以岛链周围海洋湍流的数据库。（2）使用新的嵌套方法有效地结合了上述测量的海洋电流数据，以在海洋电流模拟上，开发了海洋当前模型的新嵌套过程，并应用了海洋当前的仿真，并在海洋电流模拟上进行了上述测量方法。通过比较计算和观察到的结果，我们已经证实了本方法的基本有效性。较少的