• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.3
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• pp.123-127
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• 1978

Distributions of microplankton in two different regions of the East China Sea were studied based on the plankton samples collected by R. V. Umitaka Maru of Fisheries University of Tokyo, Japan in September, 1975. The abundance distribution and species composition of the two areas were interpreted with their temperature-salinity properties. The two areas aye characterized by differences in the depth of thermocline, the nature of surface and bottom waters, and the abundance and species composition of microplankton.

• Ocean Science Journal
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• v.42 no.3
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• pp.179-192
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• 2007

Understanding in climate effects on marine ecosystem is essential to utilize, predict, and conserve marine living resources in the 21st century. In this review paper, we summarized the past history and current status of Korean fisheries as well as the changes in climate and oceanographic phenomena since the 1960s. Ocean ecosystems in Korean waters can be divided into three, based on the marine commercial fish catches; the demersal ecosystem in the Yellow Sea and the East China Sea, the pelagic ecosystem in the Tsushima Warm Current from the East China Sea to the East/Japan Sea, and the demersal ecosystem in the northern part of the East/Japan Sea. Through the interdisciplinary retrospective analysis using available fisheries, oceanographic, and meteorological information in three important fish communities, the trend patterns in major commercial catches and the relationship between climate/environmental variability and responses of fish populations were identified. Much evidence revealed that marine ecosystems, including the fish community in Korean waters, has been seriously affected by oceanographic changes, and each species has responded differently. In general, species diversity is lessening, and mean trophic level of each ecosystem has decreased during the last $3\sim4$ decades. Future changes in fisheries due to global warming are also considered for major fisheries and aquaculture in Korean waters.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.4 no.1
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• pp.1-12
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• 1986

An attempt to obtain equipotential surface over the East China Sea along the three SEASAT ground tracks are described. Total correction of sea surface heights above the reference ellipsoid provided by SEASAT GDR Altimeter data consists of ocean tides and surges, body tides, sea level pressure inverse barometer effect corrections for the present study. It was shown that three equipotential surface derived from the corrections were qualitatively in agreement with GEM l0B Model and SS3 Mean Sea Surface Model.

• Water for future
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• v.21 no.2
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• pp.183-192
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• 1988

The previous two-dimensional non-linear tidal model of the East China Sea(Choi, 1980) has been further refined to resolve the flow over the ocntinental shelf in more detail. The mesh resolution of the present finite-difference grid system used is 4 minutes latitude by 5 minutes longitude over the entire shelf. The developed fine grid two-dimensional model was utilized to reproduce the $M_2$ tide and $M_4$ tide for the East China Sea contnental shelf. There is general agreement between the model results and the current observation made in the Eastern Yellow Sea, which supports the calculated tidal regime over the shelf. Some preliminary results on maximum bottom stress and tidally-induced residual current were also examined and discussed.

• Strategy21
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• s.33
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• pp.37-64
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• 2014

The year 2010 has been regarded as a year of China's assertive diplomacy. A series of China's behavior--including China's critical reaction to the U.S. for its sales of weapons to Taiwan, the Dalai Lama's visit to President Obama, China's arbitrary designation of 'core interests' over the South China Sea, China's inordinate reactions to the sinking of the Cheonan and Yeonpyeong bombardment, and China's activities in the Senkaku/Diaoyu island areas--has served as the witnesses to China's assertive diplomacy in 2010. The major causes of China's assertive diplomacy can be summed up by three factors: potential power transition from U.S. to China; emerging China's nationalism; and the recession of the Tao Guang Yang Hui as a diplomatic principle. But a majority of Western sinologists claim that China's assertive diplomacy is defensive in terms of its character. China's neighboring states, however, perceive its assertive diplomacy as diplomatic threat. Due to these states' geographical proximity and capability gaps with China, these neighbors experience difficulties in coping with China's behavior. In particular, China's coercive economic diplomacy, in which China tends to manipulate the neighbors' economic dependency on China for its diplomatic leverage, is a case in point for China's assertive diplomacy. China's assertiveness seems to be continued even after the inauguration of Xi Jinping government. Although the Xi government's diplomatic rhetorics in "New Type of Great Power Relationship" and the "Convention for Neighboring States Policy" sound friendly and cooperative, its subsequent behavior, like unilateral announcement of Chinese Air Defense Identification Zone (CADIZ), does not conform with its rhetoric. Overall, China's assertiveness has been consolidated as a fashion of its diplomacy, and it is likely to continue in its relations with neighbors. As a neighboring state, the ROK should approach to it with more balanced attitude. In addition, it needs to find out a new diplomatic leverage to deal with China in accordance with its security environment, in which China plays a growing role.

• Journal of the Korean earth science society
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• v.26 no.7
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• pp.714-724
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• 2005

The East Sea, a semi-enclosed marginal sea with shallow straits in the northwest Pacific, is marked by the nearly geographic isolation and the low sea surface salinity during the last glacial maximum (LGM). The East Sea might have the only connection to the open ocean through the Korea Strait with a sill depth of 130 m, allowing the paleo-Tsushima Water to enter the sea during the LGM. The low paleosalinity associated with abnormally light $\delta^{18}O$ values of planktonic foraminifera is interpreted to have resulted from river discharge and precipitation. Nevertheless, two LGM features in the East Sea are disputable. This study attempts to estimate volume transport of the paleo-Tsushima Water via the Korea Strait and further examines its effect on the low sea surface salinity (SSS) during the lowest sea level of the LGM. The East Sea was not completely isolated, but partially linked to the northern East China Sea through the Korea Strait during the LGM. The volume transport of the paleo-Tsushima Water during the LGM is calculated approximately$(0.5\~2.1)\times10^{12}m^3/yr$ on the basis of the selected seismic reflection profiles along with bathymetry and current data. The annual influx of the paleo-Tsushima Water is low, compared to the 100 m-thick surface water volume $(about\;79.75\times10^{12}m^3)$ in the East Sea. The paleo-Tsushima Water influx might have changed the surface water properties within a geologically short time, potentially decreasing sea surface salinity. However, the effect of volume transport on the low sea surface salinity essentially depends on freshwater amounts within the paleo-Tsushima Water and excessive evaporation during the glacial lowstands of sea level. Even though the paleo-Tsushima Water is assumed to have been entirely freshwater at that time period, it would annually reduce only about 1‰ of salinity in the surface water of the East Sea. Thus, the paleo-Tsushima Water influx itself might not be large enough to significantly reduce the paleosalinity of about 100 m-thick surface layer during the LGM. This further suggests contribution of additional river discharges from nearby fluvial systems (e.g. the Amur River) to freshen the surface water.

• Journal of the Korean earth science society
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• v.39 no.1
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• pp.1-22
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• 2018

Eight different data sets are examined in order to gain insight into the surface heat flux traits of the East Asian marginal seas. In the case of solar radiation of the East Sea (Japan Sea), Coordinated Ocean-ice Reference Experiments ver. 2 (CORE2) and the Objectively Analyzed Air-Sea Fluxes (OAFlux) are similar to the observed data at meteorological stations. A combination is sought by averaging these as well as the Climate Forecast System Reanalysis (CFSR) and the National Centers for Environmental Prediction (NCEP)-1 data to acquire more accurate surface heat flux for the East Asian marginal seas. According to the Combination Data, the annual averages of net heat flux of the East Sea, Yellow Sea, and East China Sea are -61.84, -22.42, and $-97.54Wm^{-2}$, respectively. The Kuroshio area to the south of Japan and the southern East Sea were found to have the largest upward annual mean net heat flux during winter, at -460- -300 and at $-370--300Wm^{-2}$, respectively. The long-term fluctuation (1984-2004) of the net heat flux shows a trend of increasing transport of heat from the ocean into the atmosphere throughout the study area.

• Journal of Korea Port Economic Association
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• v.17 no.2
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• pp.139-166
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• 2001

Globalization and regionalization are major trends in the international economic system. The severe competition among countries has signalled the need for a new international trade system as prescribed by the WTO, which regulates international trade practices. Additionally, expanding the activities and role of the Pan-Yellow Sea area in the world has a very important function in terms of regional cooperation and logistics environment. In this paper, the trading conditions and shipping transport problems of the Pan-Yellow Sea area (North-East Asia) were investigated. Shipping transport conditions in the Pan-Yellow Sea area, particularly Korea-China routes, were surveyed as well. A new Incheon-China container liner route was suggested as a partial remedy to some of the shipping transport problems of the Pan-Yellow Sea Area (North-East Asia). The Incheon-China Container Liner route is more efficient than Pusan and Pyungtaek Ports or the car ferry route to China in terms of transport time and expense. The transport burden indicator which includes the time and expense of transport, can be a useful tool in comparing these routes. Accordign to the transport burden indicator, the Incheon-China Container Liner route is more efficient than the Pusan, Pyungtaek, or car ferry routes. To establish a successful liner route between the ports of Inchon and China, there is a need to prepare three measures that contain short-term medium-term and long-term strategies. Furthermore, these measures should be prepared and adopted in phases, in accordance with considerations of future conditions for shipping and logistics in the Pan-Yellow Sea area.

• Ocean and Polar Research
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• v.32 no.4
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• pp.351-359
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• 2010

This study examined extensive patches of floating green macroalgal (Ulva prolifera) mats in the northern East China Sea (ECS) using satellite images from mid May through July 2008 and field observation made during early August 2008 cruise. It was previously reported that the massive macroalgal blooms occurred in the coastal areas of Qingdao in China. During our field survey, researchers noticed widely distributed floating patches of macroalgal mats ranging in size from tens of centimeters to a few hundred meters in diameter. Meteorological data in the northern ECS showed high irradiance, high air-temperature, and predominant southerly winds in summer. In the study area during the survey period, surface waters were characterized by the Changjiang Diluted Water (CDW) mass, which contained high concentrations of nitrate and phosphate. The internal transcribed spacer (ITS) sequence of U. prolifera found in the northern ECS was the same as those of U. prolifera sampled from Qingdao blooms, suggesting a possibility that U. prolifera found in two regions would be derived from the same origin. We suggest that U. prolifera in the nearshore Jiangsu Province drifted into the northern ECS and proliferated under favorable meteorological and oceanographic conditions during the summer of 2008.

• 한국해양학회지
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• v.20 no.1
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• pp.56-73
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• 1985

The three-dimensional hydrodynamic numerical model of the Yellow Sea and the East China Sea has been further utilised to provide S$\sub$2/,K$\sub$1/,O$\sub$1/ tidal currents distribution in addition to previously provided M$\sub$2/ tidal current distribution(Choi, 1984), especially the vertical variation of horizontal current in the region. Model results have been compared with current meter data acquired from recent China-USA Marine Sedimentation Dyamics Programme (Larsen and Cannon, 1983). Results were also used to provide maps of the S$\sub$2/,K$\sub$1/,O$\sub$1/ tidal current constants and tidal ellipses at three depths to complement previous M$\sub$2/ tidal current information.