• Title/Summary/Keyword: Coastal ocean

Search Result 4,498, Processing Time 0.023 seconds

Application of a Large Ocean Observation Buoy in the Middle Area of the Yellow Sea (황해중부해역에서의 대형 해양관측부이의 운용)

  • Shim, Jae-Seol;Lee, Dong-Young;Kim, Sun-Jeong;Min, In-Ki;Jeong, Jin-Yong
    • Ocean and Polar Research
    • /
    • v.31 no.4
    • /
    • pp.401-414
    • /
    • 2009

  • Yellow Sea Buoy (YSB) was moored in the center of the Yellow Sea at 35$^{\circ}$51'36"N, 124$^{\circ}$34'42"E, on 12 September 2007. YSB is a large buoy of 10 m diameter, and as such is more durable against collision by ships and less likely to be lost or removed by fishing nets compared to small ordinary buoys of 2.3 m diameter. YSB is equipped with 12 kinds of oceanic and meteorologic instruments, and transfers its realtime observation data to KORDI through ORBCOMM system every 1 hour. Data on ocean winds, air temperature, air pressure, and sea temperature appear to be accurate, while water property sensors (AAQ1183), which are sensitive to fouling, are producing errors. YSB (2007), Ieodo ocean research station (2003), and Gageocho ocean research station, which was completed in October 2009, will establish the 2 degrees interval by latitude in the Yellow Sea, and they will contribute though the 'Operational Oceanography System' as the important realtime observation network.

  • https://doi.org/10.4217/OPR.2009.31.4.401 인용 PDF

Field Observation and Quasi-3D Numerical Modeling of Coastal Hydrodynamic Response to Submerged Structures

  • Yejin Hwang;Kideok Do;Inho Kim;Sungyeol Chang
    • Journal of Ocean Engineering and Technology
    • /
    • v.37 no.2
    • /
    • pp.68-79
    • /
    • 2023

  • Even though submerged breakwater reduces incident wave energy, it redistributes the coastal area's wave-induced current, sediment transport, and morphological change. This study examines the coastal hydrodynamics and the morphological response of a wave-dominated beach with submerged breakwaters installed through field observation and quasi-3D numerical modeling. The pre-and post-storm bathymetry, water level, and offshore wave under storm forcing were collected in Bongpo Beach on the East coast of Korea and used to analyze the coastal hydrodynamic response. Four vertically equidistant layers were used in the numerical simulation, and the wave-induced current was examined using quasi-3D numerical modeling. The shore normal incident wave (east-northeast) generated strong cross-shore and longshore currents toward the hinterland of the submerged breakwater. However, the oblique incident wave (east-southeast) induced the southeastward longshore current and the sedimentation in the northeast area of the beach. The results suggested that the incident wave direction is a significant factor in determining the current and sediment transport patterns in the presence of the submerged breakwaters. Moreover, the quasi-3D numerical modeling is more appropriate for estimating the wave transformation, current, and sediment transport pattern in the coastal area with the submerged breakwater.

  • https://doi.org/10.26748/KSOE.2022.045 인용 PDF

Distribution Characteristics on the Parameters of Vertical Tidal Current Profile at Uldolmok, Jindo, Korea (진도 울돌목의 조류 연직 프로파일 매개변수 분포 특성)

  • Ko, Dong Hui;Park, Jin Soon;Cho, Hong Yeon;Park, Jun Seok;Lee, Gi Seop;Choi, Hyukjin
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.29 no.6
    • /
    • pp.279-285
    • /
    • 2017

  • In general, the power law and logarithmic profile are commonly used as flow vertical velocity profile model. However, since the parameters of profile vary with characteristics of coastal environment, it is necessary to estimate these values from measured data using regression analysis. In this paper, we estimated the power law exponent (n), friction velocity ($u^*$) and roughness length ($z_0$) of logarithmic profile by analyzing measured tidal current data that are averaged at a interval of 30 min. In the results of analysis, power law exponent (n) was estimated to be about 10.75 during flood and about 9.3 during ebb. Meanwhile, $u^*$ of logarithmic profile was estimated to be about 0.084 m/s, 0.105 m/s during flood and ebb, respectively. Also, $z_0$ was estimated to be 0.004 m and 0.006 m, respectively.

  • https://doi.org/10.9765/KSCOE.2017.29.6.279 인용 PDF KSCI