• Title/Summary/Keyword: Ocean circulation

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TIPEX (Tropical Indo-Pacific water transport and ecosystem monitoring EXperiment) Program (태평양-인도양 해양순환 연구 프로그램)

  • Jeon, Dongchull;Kim, Eung;Shin, Chang Woong;Kim, Cheol-Ho;Kug, Jong Seong;Lee, Jae Hak;Lee, Youn-Ho;Kim, Suk Hyun
    • Ocean and Polar Research
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    • v.35 no.3
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    • pp.259-272
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    • 2013
  • One of the factors influencing the climate around Korea is the oceanic-atmospheric variability in the tropical region between the eastern Indian and the western Pacific Oceans. Lack of knowledge about the air-sea interaction in the tropical Indo-Pacific region continues to make it problematic forecasting the ocean climate in the East Asia. The 'Tropical Indo-Pacific water transport and ecosystem monitoring EXperiment (TIPEX)' is a program for monitoring the ocean circulation variability between Pacific and Indian Oceans and for improving the accuracy of future climate forecasting. The main goal of the TIPEX program is to quantify the climate and ocean circulation change between the Indian and the Pacific Oceans. The contents of the program are 1) to observe the mixing process of different water masses and water transport in the eastern Indian and the western Pacific, 2) to understand the large-scale oceanic-climatic variation including El Nino-Southern Oscillation (ENSO)/Warm Pool/Pacific Decadal Oscillation (PDO)/Indian Ocean Dipole (IOD), and 3) to monitor the biogeochemical processes, material flux, and biological changes due to the climate change. In order to effectively carry out the monitoring program, close international cooperation and the proper co-work sharing of tasks between China, Japan, Indonesia, and India as well as USA is required.

The Impact of Southern Ocean Thermohaline Circulation on the Antarctic Circumpolar Current Transport

  • Kim, Seong-Joong;Lee, Bang-Yong
    • Journal of the Korean Geophysical Society
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    • v.9 no.4
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    • pp.291-299
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    • 2006
  • The observed ocean barotropic circulation is not completely explained by the classical wind-driven circulation theory. Although it is believed that the thermohaline forcing plays a role in the ocean barotropic circulation to some degree, how much the thermohaline forcing contributes to the barotropic circulation is not well known. The role of thermohaline circulation driven by changes in temperature and salinity in the Southern Ocean (SO) water masses on the Antarctic Circumpolar Current (ACC) transport is investigated using a coupled ocean - atmosphere - sea ice - land surface climate system model in a Last Glacial Maximum (LGM) context. Withthe implementation of glacial boundary conditions in a coupled model, a substantial increase in the ACC transport by about 75% in 80 years of integration and 25% in the near LGM equilibrium is obtained despite of the decreases in the magnitude of wind stresses over the SO by 33% in the transient time and 20% in the near-equilibrium. This result suggests that the increase in the barotropic ACC transport is due to factors other than the wind forcing. The change in ocean thermohaline circulation in the SO seems to play a significant role in enhancing the ACC transport in association with the change in the bottom pressure torque.

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An Optimization Approach to the Wind-driven Ocean Circulation Model (해수순환모델에 대한 최적화 방법)

  • KIM Jong-Kyu;RYU Cheong-Ro;CHANG Sun-duck
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.6
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    • pp.787-793
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    • 1994
  • It has been demonstrated for the finite-difference ocean circulation model that the problem of uncertain forcing and input data can be tackled with an optimization techniques. The uncertainty problem in interesting flow properties is exploring a finite difference ocean circulation model due to the uncertainty in the driving boundary conditions. The mathematical procedure is based upon optimization method by the conjugate gradient method using the simulated data and a simple barotropic model. An example for the ocean circulation model is discussed in which wind forcing and the steady-state circulation are determined from a simulated stream function.

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Numerical Experiment of Environmental Change in the East China Sea under Climate Change (기후변화에 따른 동중국해 해양 순환 변화 예측에 대한 수치 실험 연구)

  • Min, Hong Sik;Kim, Cheol-Ho
    • Ocean and Polar Research
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    • v.34 no.4
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    • pp.431-444
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    • 2012
  • We simulated and compared present and future ocean circulation in the East China Sea using an East Asia Regional Ocean model. Mean climate states for 1990~1999 and 2030~2039 were used as surface conditions for simulations of present and future ocean circulation, which were derived from the simulations of three different global climate models, ECHAM5-MPI, GFDL-CM2.0 and MIROC3.2_hires, for the 20th century and those of 21st century as projected by the IPCC SRES A1B. East Asia Regional Ocean model simulated the detailed patterns of temperature, salinity and current fields under present and future climate conditions and their changes instead of the simple structures of global climate models. To some extent, there are consistent ocean circulation changes derived from the three pairs corresponding to the global climate model in so much as the temperature increases not only in winter but summer at both the surface and bottom and that temperature and salinity changes are prominent near the Chinese coast and in the Changjiang bank. However, the simulated circulations are different among each other depending on the prescribed atmospheric conditions not only under present climate but also with regard to future climate conditions. There is not a coincident tendency in ocean circulation changes between present and future simulations derived from the three pairs. This suggests that more simulations with different pairs are needed.

The Improvement of Circulation System in Theme Park - Focused on the EXPO Ocean Park in Yeosu - (주제공원의 동선 개선 제안 - 여수 엑스포 해양공원을 대상으로 -)

  • Park, Hyo-Chul;Han, Hye-Sun
    • Korean Institute of Interior Design Journal
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    • v.23 no.5
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    • pp.202-210
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    • 2014
  • The EXPO Ocean Park in Yeosu has taken on the apsect of a theme park and has specialized facilities. But the outdoor circulation system that has been used by Expo 2012 Yeosu Korea still remained. These conditions can occur unused circulation and a long walk between facilities. The Purpose of this study is to suggest the improvement of circulation system that uses walking and outdoor space at the Expo Ocean Park in Yeosu. The following researches are drawn based upon the purpose. First, Definition and existing academic literature of theme park is considered. Second, the type, utilization condition, and circulation of outdoor facilities of Expo Ocean Park are investigated through the field survey and analysis. The field survey is conducted on the Expo Ocean Park in Yeosu for five times from October. 2013 to March. 2014. The data is collected through the photographed outdoor park and interviewing the staff of 2012 Yeosu World Expo Foundation. Third, the case study on outdoor circulation of waterside park and park with amusement facilities that are similar to Expo Ocean Park are examined. The result of this study is expected to seek sustainable management of Expo Ocean Park for maximizing local resident and visitors' satisfaction and improving effective park image. Since the field survey was conducted before the park is reopened and The Expo Ocean Park is on the improve through the this study at present, the verification of improvement scheme based on Post-Occupancy Evaluation(POE) is needed for future study.

Modeling of Ocean Circulation in the Neighboring Seas of Korean Peninsula from Global Ocean Circulation Model (전구 해수순환 수치모형에 의한 한반도 주변의 순환 모사)

  • Choi Bung Ho;Choi Young Jin;Kim Cheol Ho
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.16 no.4
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    • pp.241-257
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    • 2004
  • Global prognostic models based on NCOM(NCAR CSM Ocean Model) of NCAR which is generic from Bryan-Cox-Semtner model are established to study the ocean circulation in the neighboring seas of Korean peninsula. The model domain covers areas from $80.6{^\circ}S~88.6{^\circ}N$in meridional direction and the vertical water column is divided into 15 levels taking enhanced grid resolution of $0.3^\circ$ around Korean peninsula. Island option is used for 22 islands to simulate inshore circulation by hole-relaxation method and the restart hydrographic data are taken from NCAR(1998) CSM model that has been run for 300 years. The wind stress data are taken from Choi et al. (2002). Based on the model results, circulation patterns in the NW Pacific and global oceans are investigated. Volume transports calculated at five straits in the neighboring seas of Korean peninsula are compared with the results from Choi et al. (2002) and other observed data.

Three-dimensional Numerical Modelling of Seawater Circulation of Semi-enclosed Bay with the Flow-control Structures

  • JONG-KYU KIM;TAE-SOON KANG;HEON-TAE KIM
    • Journal of Ocean Engineering and Technology
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    • v.15 no.3
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    • pp.35-42
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    • 2001
  • The characteristics of tidal circulation with the flow-control structures using the three-dimensional numerical model (POM, Princeton Ocean Model) of Chinhae Bay, Korea were investigated. To confirm th efficiencies of flow-control structures, the training wall and submerged training wall were constructed at the mouth and narrow channel in Chinhae Bay. On the basis of the present investigation, the tidal circulation induced by the construction of flow-control structures could enhance the water exchange improvement appropriately. And, th training wall at the central is more dominated than the other structures for the efficient of water exchange. The sites and types of structure and flow patterns seem to be very sensitive in tidal simulation and changes in flow fields.

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Authigenic Neodymium Isotope Record of Past Ocean Circulation (과거 해수 순환을 지시하는 해수기원 네오디뮴 동위원소 비 기록)

  • Huh, Youngsook;Jang, Kwangchul
    • The Journal of the Petrological Society of Korea
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    • v.23 no.3
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    • pp.249-259
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    • 2014
  • Proxies for paleo-circulation are drawing much interest with the recognition that ocean circulation plays an important part in the redistribution of heat and climate change on orbital and millennial timescales. In this review, we will introduce how neodymium isotope ratios of the authigenic fraction of marine sediments can be used as a proxy for ocean circulation along with analytical methods and two case studies. The first case study shows how the North Atlantic Deep Water (NADW) has varied over the glacial-interglacial and stadial-interstadial periods. The second case study shows how the freshwater budget and water circulation within the Arctic Ocean can be reconstructed for the last glacial period.

Evaluation of Temperature and Salinity Fields of HYCOM Reanalysis Data in the East Sea (HYCOM 재분석 자료가 재현한 동해 수온 및 염분 평가)

  • Hong, JinSil;Seo, Seongbong;Jeon, Chanhyung;Park, Jae-Hun;Park, Young-Gyu;Min, Hong Sik
    • Ocean and Polar Research
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    • v.38 no.4
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    • pp.271-286
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    • 2016
  • We evaluate the temperature and salinity fields in the East Sea reproduced by the global ocean reanalysis data using HYbrid Coordinate Ocean Model (HYCOM for short). Temporal correlation of Sea Surface Temperature (SST) change between HYCOM and the Group for High Resolution Sea Surface Temperature (GHRSST) are higher in summer than winter. Though distributions of temperature and salinity in the HYCOM are similar to those from historical data (World Ocean Atlas 2013 V2), salinity in the HYCOM is lower (highter) in the region where the salinity is high (low). Temperature fields in the Ulleung basin of HYCOM are quite similar to those derived from Pressure-recording Inverted Echo Sounder (PIES), such as the correlation coefficient is higher than 0.7. This indicates that the HYCOM represents well the circulation and meso-scale phenomena in the Ulleung basin.

A Second-Order Particle Tracking Method

  • Lee, Seok;Lie, Heung-Jae;Song, Kyu-Min;Lim, Chong-Jeanne
    • Ocean Science Journal
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    • v.40 no.4
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    • pp.201-208
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    • 2005
  • An accurate particle tracking method for a finite difference method model is developed using a constant acceleration method. Being assumed constant temporal and spatial gradients, the new method permits temporal-spatial variability of particle velocity. Test results in a solid rotating flow show that the new method has second-order accuracy. The performance of the new method is compared with that of other methods; the first-order Euler forward method, and the second-order Euler predictor-corrector method. The new method is the most efficient method among the three. It is more accurate and efficient than the other two.