• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.2
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• pp.151-163
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• 1992

Seasonal variations of water mass distributions in the Yellow Sea, the East China Sea, and the adjecent seas of Cehju Island, are investigated. A common seasonal variation over these whole areas is shown. Warm and saline waters are extended northwestward into the Yellow Sea in winter and retreated back southeastward to the East China Sea in summer. Barotropic numerical model results suggest that monsoon winds could drive such seasonal variations. Upwind flows play an important role in the processes. In the numerical model results, upwind flows are shifted to China. It is due to energy dissipations by complicated coast lines and shallow bottom topographies in the northern part of the Yellow Sea. The shifted routes of upwind flows agrees well with that of the southward extensions of the Yellow sea Bottom Cold Waters in summer.

• Korean Journal of Remote Sensing
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• v.37 no.5_2
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• pp.1307-1315
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• 2021

The Changjiang Diluted Water (CDW) spreads over the East China Sea every summer and significantly affects the sea surface salinity changes in the seas around Jeju Island and the southern coast of Korea peninsula. Sometimes its effect extends to the eastern coast of Korea peninsula through the Korea Strait. Specifically, the CDW has a significant impact on marine physics and ecology and causes damage to fisheries and aquaculture. However, due to the limited field surveys, continuous observation of the CDW in the East China Sea is practically difficult. Many studies have been conducted using satellite measurements to monitor CDW distribution in near-real time. In this study, an algorithm for estimating Sea Surface Salinity (SSS) in the East China Sea was developed using the Geostationary Ocean Color Imager (GOCI). The Multilayer Perceptron Neural Network (MPNN) method was employed for developing an algorithm, and Soil Moisture Active Passive (SMAP) SSS data was selected for the output. In the previous study, an algorithm for estimating SSS using GOCI was trained by 2016 observation data. By comparison, the train data period was extended from 2015 to 2020 to improve the algorithm performance. The validation results with the National Institute of Fisheries Science (NIFS) serial oceanographic observation data from 2011 to 2019 show 0.61 of coefficient of determination (R²) and 1.08 psu of Root Mean Square Errors (RMSE). This study was carried out to develop an algorithm for monitoring the surface salinity of the East China Sea using GOCI and is expected to contribute to the development of the algorithm for estimating SSS by using GOCI-II.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.06a
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• pp.171-183
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• 2000

Regarding the ancient Sino-Kroea sea communication as the main theme, the propagation of the China-culture in Koran Peninsula and he influence of Chinese ancient shipbuilding technique for Korea are described in the paper. Frequent sea trade resulted in the flourishing of Chinese and Korean harbours on both side of Yellow Sea. Sino-Koran sea communication is of long-standing. Korean Peninsula (KP) is just as the large arm extended to the great sea from the North-east China. It is the Chinese mainland plate-lump's extended part in the Yellow Sea. In the ancient time, the land communication between China and Korea was often not unimpeded, the contact between China and KP, such as the South-Korea, depended on the sea communication mainly, Although the friendly relationship between China and Korea rose one after another in the various historical period, but considering from the great background of people's historical development, just as the modern people benefited fro the Europe-American culture, the people of ancient time also benefited from the China-culture. All China, KP and Japan obtained the development by propagating the ancient China-culture. The seagoing ships which carried out the Sino-Korea sea communication and trade, as the friendly envoys, finished the mission linked u and developed the Sino-Korea culture contact.

• The Journal of Fisheries Business Administration
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• v.40 no.2
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• pp.71-103
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• 2009

This study is designed to propose the ways of the multilateral cooperation system for effective management of fisheries resources in the various overlapping zones established by bilateral fisheries agreements between Korea, China and Japan in North East Asia as semi-enclosed sea. It is necessary to build multilateral fisheries cooperation between Korea, China and Japan in North East Asia because conservation & management of transboundary fish stocks could not be guaranted effectively by the management of fisheries resources in the area where piled up the current-fishing-pattern zone, as white zone and the various grey zone as middle zone, and the interim measures zone of bilateral fisheries agreements between Korea, China and Japan are piled up. Fisheries management in Korea, China and Japan by the bilateral fisheries agreements in North East Asia is faced with difficulties manage fisheries resources. International relationship on fisheries is maintained by bilateral fisheries agreements based on UNCLOS. However fisheries resources are over-exploited and the recovery of the fisheries resources is very slow because proper conservation and management of transboundary fish stocks which article 63(1) of UNCLOS defines have not prepared yet. Thus close cooperation among the coastal States for a proper conservation and management of transboundary fish stocks is necessary. Since the transboundary fish migrate within the EEZs of two or more coastal States, there is a need to manage the fish stocks in the region between Korea, China and Japan through a multi-lateral mechanism at ccircumference area of the current-fishing-pattern zone as white zone. Coastal States must guarantee sustainable maintenance of transboundary fish stocks through the regional cooperation for a proper conservation & management because one coastal State alone could not guarantee conservation and management of fish stocks. Thus there is a need to build multilateral fisheries cooperation between Korea, China and Japan in North East Asia. There are many successful instances including the Barents' sea for a proper conservation & management of transboundary fish stocks. The Barents' sea is one of the best research object to study the regional cooperation for a conservation & management of transboundary fish stocks in North East Asia. In conclusion, it is necessary to build a multilateral fisheries cooperation system between Korea, China and Japan in North East Asia to conserve and manage transboundary fish stocks effectively. It seems desirable that the range of the area to conserve and manage fish stocks should may be any partial area in the current-fishing-pattern zone and interim measures zone between Korea and China, Jeju middle zone between Korea and Japan, interim measures zone of bilateral fisheries agreements between China and Japan.

• Journal of Fisheries and Marine Sciences Education
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• v.23 no.4
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• pp.772-778
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• 2011

In order to estimate the densities and composition of floating marine debris (FMD), a sighting survey was conducted from July 1st to July 14th, 2009 in the East China Sea (ECS) using a training vessel "Kaya (1,737 ton)" of Pukyong National University. The sampled zones are divided into 5 transects by observation day during the survey days and the densities and composition in each transect were calculated using the numbers of item per $km^2$. The results of distribution of FMD are as follows: 1. During the surveys, a large variety of FMD was discovered and highest densities were found in the Central East(CE) of the East China Sea(ECS) (48.2 items/$km^2$), whereas densities in the less populated transects in Okinawa(OK1, OK2) were comparatively low(3.5 ~ 4.9 items//$km^2$). 2. Among the classified 6 items, styrofoams(Styro) were most abundant and ubiquitous(10.3 items/$km^2$, 53% of the total number), except OK2 area. Next abundant item was vinyl and plastics called V & P(4.9 items/$km^2$, 25%). Above 2 items of the major proportion of FMD accounted for 78% of the total number of FMD observed through this study. 3. The percentages of manufactured plastics(Styro and V & P) found in the Seas near Korean Peninsula were varied from 87.2% to 69.8%. It was recognized that polluted level is middle value among them.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.290-294
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• 2001

Satellite data, with Sea Surface Temperature(SST) by NOAA and Sea Level(SL) by Topex/poseidon, are used to estimate characteristics on the variations and correlations of SST and SL in the East Asian Seas from January 1993 through May 1998. In the oceanic climate, the variations of SL shown the high values in the main current of Kuroshio and the variations of SST shown not the remarkable seasonal variations because of the continuos compensation of warm current by Kuroshio. In the continental climate, SL shown high variations in the estuaries(the Yellow River, the Yangtze River) with the mixing the fresh water in the mouth of estuaries of the saline water in the coasts of continent and SST shown highly the seasonal variations due to the climatic effect of continents. In the steric variations in summer, the eastern sea of Japan, the East China Sea and the western sea of Korea shown the increment of sea level with 10~20cm. But the Bohai bay in China shown relatively the high values of 20~30cm due to the continental climate. Generally the trends of SST and SL increased during all periods. That is say, the slopes of SST and SL presented 0.29$^{\circ}C$/year and 0.84cm/year, respectively. The annual and semi-annual amplitudes shown a remarkable variations in the western sea of Korea and the eastern sea of Japan.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.327-331
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• 2007

23 tropical cyclones of tropical storm(TS) intensity or higher formed in the western North Pacific and the South China Sea in 2006. The total number is less than the 30-year $(1971{\sim}2000)$ average frequency of 26.7, Out of 23, 15 cyclones reached typhoon(TY) intensity, three severe tropical storm(STS) intensity, and five TS intensity. The tropical cyclone season in 2006 began in May with the formation of CHANCHU(0601). While convective activity was slightly inactive around the Philippines from late June to early August. In addition, subtropical high was more enhanced than normal over the south of Japan from May to early August. Consequently, most tropical cyclones formed over the sea east of the Philippines after late June, and many of them moved westwards to China. CHANCHU(0601), BILIS(0604), KAEMI(0605), PRAPIROON(0606) and SAOMI(0608) brought damage to China, the Philippines, and Vietnam. On the other hand, EWINIAR(0603) moved northwards and hit the Republic of Korea, causing damage to the country From late August to early September, convective activity was temporarily inactive over the sea east of the Philippines. However, it turned active again after late September. Subtropical high was weak over the south of Japan after late August. Therefore, most tropical cyclones formed over the sea east of the Philippines and moved northwards. WUKONG(0610) and SHANSHAN(0613) hit Japan to bring damage to the country. On the other hand, XANGSANE(0615) and CIMARON(0619) moved westwards in the South China Sea, causing damage to the Philippines, Thailand, and Vietnam. In addition, IOKE(0612) was the first namded cyclone formed in the central North Pacific and moved westwards across longitude 180 degrees east after HUKO(0224).

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.192-199
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• 2004

The distribution of dinofagellate cysts in the top-3 cm surface sediment samples collected from the East China Sea around Jeju Island was investigated in 18 stations of the sea. Twenty-two different types of Dinoflagellate cysts were recorded in this study, among which Spiniferites bulloideus occupied a predominant species in most of all the stations. Dinoflagellate cyst concentration varied from 6 (st. B3) to 3,645 (st. A5) cysts $g^{-1}$, and generally increased toward the northern part of Jeju Island (Part 1) rather than the southern part (Part 2); in the former average value was 183 cysts $g^{-1}$, while that in the latter was 1,144 cysts$g^{-1}$. Compared with the other reports which investigated dinoflagellate cyst concentrations and distributions in the East China Sea, the results in this study showed very similar pattern to those.

• Ocean and Polar Research
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• v.33 no.2
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• pp.135-147
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• 2011

Zooplankton is an important constituent in assessing ecosystem responses to global warming. The northern East China Sea is an important ecosystem for carbon cycling with a net sink of carbon dioxide. Despite their importance as a major component in carbon cycling, relatively little is known about zooplankton biomass structure and its regulating factors in the northern East China Sea. This study examined zooplankton biomass distribution pattern in the region from multiple cruises encompassing various seasons between 2004 and 2009. Results showed that zooplankton biomass exhibits less cross-shelf gradient in general with declining biomass to the eastern shelf towards the Tsushima Current Water. Size-fractionated biomass showed that the 1.0~2.0 mm size group, mostly copepods, dominated zooplankton biomass, comprising 38 to 48% of total biomass. Smaller zooplankton (0.2~1.0 mm) biomass, consisting mainly of Paracalanus spp, a particle eating herbivorous copepod, was positively related to chlorophyll-a concentration, but no relationship was established for larger zooplankton (1.0~5.0 mm). Spatially-averaged mean total zooplankton biomass was also highly related to chlorophyll-a concentration. These result suggest that the long-term trend of zooplankton biomass increase in this region is partly accounted for by the increases of phytoplankton biomass and productivity underway in the region. However, the underlying mechanisms of how sea surface warming in the study area leads to increased phytoplankton biomass and productivity remains unclear.

• Fisheries and Aquatic Sciences
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• v.3 no.1
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• pp.8-13
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• 2000

Monthly mean chlorophyll concentration in the East Sea was estimated from the ocean color observed by the Coastal Zone Color Scanner (CZCS) on Nimbus-7 satellite which had performed various remote sensing missions from 1979 to 1986. The areas of high chlorophyll concentration were found in the sea between Siberia coast and Sakhalin Island, in the Donghan Bay and in the Ulleung Basin. In the southwestern East Sea, especially in the area near Ulleung Island, the yearly maximum chlorophyll concentration occurred in December. The chlorophyll concentration in Ulleung Basin in December was about two times higher than during spring bloom in April. The early winter bloom occurred in the warm side of the front that was formed between warm water from the East China Sea and nutrition rich cold water from the northern East Sea.