• 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

• Korean Journal of Remote Sensing
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• v.13 no.1
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• pp.1-12
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• 1997

The western equatorial Pacific Ocean, where sea surface temperature is the warmest on the globe, is characterized by numerous convective systems and large annual precipitation. In this region, the cloudiness data with tops higher than 8km level obtained from the GMS-IR data are used to investigate the diurnal variation of cloudiness. The amplitude and phase of diurnal and semi-diurnal cycles are mainly investigated to examine details on the temporal and spatial structure of clouds. Cloudiness variation has typical cycles and each cycle is associated with the air-sea interactive phenomena. Spectral analysis on the cloudiness time series data indicates that 30-60 day, 17-20day, 7-8 day, diurnal and semi diurnal cycle are peaked. During Northern Winter and Southern Summer, the large cloudiness exsists over New Guinea, the adjacent seas of North Australia, and the open oceanic regions east of $160^{\circ}$E. Cloudiness diurnal variability over the lands and their adjacent seas is about 2.0 times larger than that over the open sea regions. That may be due to the difference of specific heat between the land and sea. The maximum and minimum cloudiness appeared at 18:00 and 09:00 hours over the land, and at noon and 21:00 hours over the sea, respectively. The amplitude of diurnal component over the land is 4,7 times larger than that of semi-diurnal component, and 1.5 times over the sea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.316-329
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• 1983

The formation and structure of the shelf front in the eastern part of the Yellow Sea are studied on the basis of oceanographic data collected in August, 1982 and February, 1983. This paper also describes the distribution of planktonic organisms of the shelf front. In summer the shelf front is formed in the area ($126^{\circ}02^'E-126^{\circ}05^'E$) ca. 20 miles from the shore at the depths of 15-25 m. in winter, however, no distinct shelf front is formed. Based on the cluster analysis of surface phytoplankton the species composition shaws a discontinuous pattern in the vicinity of the shelf front in summer, 1982. A similar trend is observed in distribution of some copepod species in winter, l983.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.28 no.1
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• pp.1-18
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• 2023

The East Sea, one of the regions where the most rapid warming is occurring, is known to have important implications for the response of the ocean to future climate changes because it not only reacts sensitively to climate change but also has a much shorter turnover time (hundreds of years) than the ocean (thousands of years). However, the processes underlying changes in seawater characteristics at the sea's deep and abyssal layers, and meridional overturning circulation have recently been examined only after international cooperative observation programs for the entire sea allowed in-situ data in a necessary resolution and accuracy along with recent improvement in numerical modeling. In this review, previous studies on the physical characteristics of seawater at deeper parts of the East Sea, and meridional overturning circulation are summarized to identify any remaining issues. The seawater below a depth of several hundreds of meters in the East Sea has been identified as the Japan Sea Proper Water (East Sea Proper Water) due to its homogeneous physical properties of a water temperature below 1℃ and practical salinity values ranging from 34.0 to 34.1. However, vertically high-resolution salinity and dissolved oxygen observations since the 1990s enabled us to separate the water into at least three different water masses (central water, CW; deep water, DW; bottom water, BW). Recent studies have shown that the physical characteristics and boundaries between the three water masses are not constant over time, but have significantly varied over the last few decades in association with time-varying water formation processes, such as convection processes (deep slope convection and open-ocean deep convection) that are linked to the re-circulation of the Tsushima Warm Current, ocean-atmosphere heat and freshwater exchanges, and sea-ice formation in the northern part of the East Sea. The CW, DW, and BW were found to be transported horizontally from the Japan Basin to the Ulleung Basin, from the Ulleung Basin to the Yamato Basin, and from the Yamato Basin to the Japan Basin, respectively, rotating counterclockwise with a shallow depth on the right of its path (consistent with the bottom topographic control of fluid in a rotating Earth). This horizontal deep circulation is a part of the sea's meridional overturning circulation that has undergone changes in the path and intensity. Yet, the linkages between upper and deeper circulation and between the horizontal and meridional overturning circulation are not well understood. Through this review, the remaining issues to be addressed in the future were identified. These issues included a connection between the changing properties of CW, DW, and BW, and their horizontal and overturning circulations; the linkage of deep and abyssal circulations to the upper circulation, including upper water transport from and into the Western Pacific Ocean; and processes underlying the temporal variability in the path and intensity of CW, DW, and BW.