• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.175-181
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• 1999

A recurring eddy which located at the terminal end of the Korean East Warm Current was captured on ocean color and sea surface temperature imagery from satellite in spring and autumn. During late April, 1997 thermal infrared imagery from the NOAA AVHRR sensor and ocean color data from the Japanese ADEOS-I OCTS sensor, revealed this feature. The cold core had elevated chlorophyll concentrations, based on OCTS estimates, of greater than 3 mg/m$^3$ while the warmer surrounding waters had chlorophyll concentrations of 1 mg/m$^3$ or less. The elevated cholophyll accociated with this eddy has not been previously described. The eddy is also evident in SST images from autumn, but the SST in the core is warmer than in spring, and the warm jet flowing to the west of the eddy is also warmer is autumn compared to spring. A reccurring eddy and the high chlorophyll_a concentration area which surround around the eddy show on NOAA and SeaWiFS images in March 2, 1998. The eddy forms at the northern extent of the Korean East Warm Current as those waters collide with the cold, south-flowing Liman Current over a topographic shelf about 1500 m deep. This region of the eddy formation appears to have a strong connection with the dynamics of the western part of the polar front eddy field that dominates surface mesoscale structure in the central East (Japan) Sea. Interaction of the eddy with ARGOW tracked drifters, and evidence for its persistence are discussed.

• Proceedings of the Korean Society of Computer Information Conference
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• 2015.07a
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• pp.99-100
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• 2015

본 논문에서는 해양현상의 하나인 와동류를 컴퓨터 환경에서 모의하는 방안에 대해 제안한다. 이를 위해 와동류의 구조적 특징을 분석하고 이와 유사하게 모의하는 방안을 소개한다. 또한 해양 분야에서 가장 널리 사용되는 netCDF 포맷의 실 수온데이터를 이용하여 와동류를 표현하고 NASA에서 제공하는 공개 분석 툴을 이용하여 결과를 비교 분석한다. 또한 모의한 와동류가 실제 해양전투 모의실험에서 어떻게 활용 될 수 있는지 그 활용방안에 대해 소개한다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.354-363
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• 1995

Temporal change of a warm eddy off Sogcho was studied using satellite infrared images from January to lune 1992 and its structure was investigated by the observations in Hay. There were two kinds of event for eddy formation. IR images in January indicated that the eddy Haying a horizontal dimension of about 200km was first formed by an injection of warm water. After some deformation and cooling processes the second restrengthening event took place in late March when a warm filament began to penetrate northward and circumvented the preexisting eddy. This eddy became a complete ring-shape with cooled water arrested inside from April to May. The maximum thickness of the isothermal subsurface layer with temperature of $10.0-10.4^{\circ}C$ was about 170m. Except that the current velocity was about 80cm/sec near the axis of the last Korea Warm Current close to Sogcho, the interior of the eddy had an anticyclonic motion with overall swirl velocity of 30-50cm/sec. Velocity rapidly decreased vertically below the main thermocline.

• Korean Journal of Remote Sensing
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• v.16 no.3
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• pp.211-220
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• 2000

Even though recurring eddies at the terminal end of the East Korean Warm Current have been identified in the thermal infrared imagery from the NOAA/AVHRR sensor and ocean color data from Orbview-2/SeaWiFS sensor, it is difficult to make observation in the field regarding recurring eddies located around the Wonsan coastal area in North Korea. But we could get in situ data related to an eddy from an ARGOS satellite tracking drifter trapped in the eddy on January 4th, 1999. An ARGOS drifter, a NOAA satellite tracked buoy was trapped by the eddy during January 4th.March 18, 1999. The ARGOS drifter rotated 10 times per 72 days on the edge of the eddy located at $39^{\circ}N$, $129^{\circ}E$. The diameter of the eddy was about 100 km. The horizontal rotation velocity of the recurring cold-core anti-cyclonic eddy was 1.53 km/h(42 cm/sec). The sea surface temperatures of the eddy varied from $14.7^{\circ}C$ on January 5, 1999 to $9.6^{\circ}C$ on March 18,1999. To study the mechanism of the recurring eddy. we tried to find out the relationship between the vector of the drifter moving in the eddy and the wind vector in Sokcho and Ulleung Island located near the eddy in southern Korea, and the difference in sea level between Ulleung Island and Mukho. We hope the results of this study would be useful for calibration and validation data of simulation and numerical modeling studies of the recurring eddy.

• Korean Journal of Remote Sensing
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• v.20 no.4
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• pp.245-252
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• 2004

The mechanism of cold core eddy formation was investigated using boundary conditions between the East China coastal cold water and the Kuroshio Warm Current, wind data related to the monsoon which was measured by QuikSCAT, and the bottom topography of the East China Sea. When winds blow from the southeast at an intensity comparable to that in the winter period in 1999 and 2003, the warm Kuroshio and Tsushima Current became stronger, and temperatures were considerably higher than those of the extended cold water of the coast of the East China. At that time, the cold water was captured by warm water from the Kuroshio and the Tsushima Current. This facilitated the formation of mesoscale cold core eddies with diameter of 150km in the East China Sea in May, 1999 and February, 2003. The cold core eddy which was detected by NOAA, SeaWiFS and QuikSCAT satellites. The East China Sea is considered to be important not only as a good fishing ground but also nursery and spawning area for many kinds of fishes. Therefore, it would be worth studying spatio-temporal variations of the cold core eddy in the environmental conditions of the northwestern East China Sea using systematic remote sensing techniques.

• Journal of the Korean Society of Marine Environment & Safety
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• v.11 no.1 s.22
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• pp.77-82
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• 2005

In order to investigate the initial stage of deep water formation between Vladivostok and the subpolar front in the East Sea, the factors, temperature, salinity, dissolved oxygen, measured by multi-ship surveys in ]969 have been used. Deep water formation in the .cast Sea occurs in essentially two different forms: near continent and open ocean formation. The position of eddy derived from potential vorticity matches well with that of deep water formation. The vertical and horizontal distributions of potential vorticity, geostrophic current, temperature, salinity and dissolved oxygen give clues for the preconditioning phase qf open ocean formation like a doming of isotherm, associated with a cyclonic circulation.

• Proceedings of KOSOMES biannual meeting
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• 2004.11a
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• pp.117-122
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• 2004

In order to investigate the initial stage of deep water formation between Vladivostok and the subpolar front in the East Sea, the factors, temperature, salinity, dissolved oxygen, measured by multi-ship surveys in 1969 have been used Deep water formation in the East Sea occurs in essentially two different forms: near continent and open ocean formation the position of eddy derived from potential vorticity matches well with that of deep water formation. The vertical and horizontal distributions of potential vorticity, geostrophic current, temperature, salinity and dissolved oxygen give clues for the preconditioning phase of open ocean formation like a doming of isotherm, associated with a cyclonic circulation

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.6
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• pp.800-809
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• 2014

The gridded environmental data is usually provided by the numerical simulation coupled with a data assimilation technique and various inter- or extrapolation algorithms, both of which are based on the observation spanning from simple equipments to satellites. But it is difficult to represent the natural phenomenon such as sea mount, internal-wave, warm eddy in modeling or observation because of increase in the complexity of model. This paper introduces the algorithm artificially representing the natural phenomenon and the techniques applying it to the gridded volume data and smoothing for natural effects. Moreover, the inserted results are analyzed by use of graphical tool. The results can be used for the battle simulation or acoustic model.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.755-758
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• 2001

Topex/poseidon 위성의 자료를 통하여 남인도양의 암스테르담- 크호제트- 케르겔른 지역에 대한 표층 순환과 해수면 변화의 시ㆍ공간적인 해석을 쉽게 수행 할 수 있었다. 각 지역에서의 시ㆍ공간적인 변화 특성들을 보면, 암스테르담지역은 서쪽으로 전파하는 로쓰비파가 존재한다. 이때 이 파는 동쪽으로 전파하는 남극순환해류의 영향을 받는다. 1993년 늦가을에서 초겨울 동안에 분지의 동부지역에서 해수면이 급격히 떨어졌다. 이곳은 남극순환해류(아규라스순환반류전선과 아열대전선)의 북부에서 발전하는 시계방향(cyclonic)의 와동류가 예외적으로 강하게 북쪽으로 상승했다가 이어서 급격히 남쪽으로 하강했던 것과 관련된다. 쌩뽈지역은 5cm 정도의 해수면 진동과 함께 약 130일 정도의 주기성을 보였다. 서쪽으로 전파하는 신호인 자유 표면의 진동이 실제로 조사되었다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.641-644
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• 2003

Sea level variability and eddy in the Amsterdam-Crozet-Kerguelen region of the South Indian Ocean were studied during 1 year(October 15, 1992~October 15, 1993) using multi-satellite data(Topex/Poseidon, ERSl) produced by signal treatement. We found that generally sea level variabilities(>10cm) exist along the Antarctic Circumpolar Current in the area of 35$^{\circ}$~46$^{\circ}$S and especially strong sea level variabilities(20~30cm) were occurred by the effects of eddy due to botton topography in two small area: 49$^{\circ}$-57$^{\circ}$E and 38$^{\circ}$~42$^{\circ}$S, and 58$^{\circ}$ -64$^{\circ}$E and 42$^{\circ}$-44$^{\circ}$S.