• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.397-402
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• 2006

China Coastal Water (CCW) usually appears in the seas surrounding Jeju Island annually (June-October) and is very pronounced in August. The power spectrum density (PSD), sea level anomalies (SLAs), and sea surface temperatures (SSTs) were found to peak annually and semiannually. The peaks at intervals of 80-, 60-, and 43-days are considered to be influenced by CCW and the Kuroshio Current. Generally, low-salinity water appears to the west of Jeju Island from June through October and gradually propagates to the east, where CCW meets the Tsushima Current. Empirical orthogonal function (EOF) analysis of SLAs and SSTs indicated that the variance in SLAs and SSTs was 55.70 and 98.09% in the first mode, respectively. The PSD for the first mode of EOF analysis of SLAs was stronger in the western than in the eastern waters because of the influence of CCW. The PSD for the EOF analysis of SSTs was similar in all areas (the Yangtze Estuary and the waters to the west and east of Jeju Island), with a period of approximately 260 days.

• Korean Journal of Remote Sensing
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• v.23 no.1
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• pp.65-69
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• 2007

The processes of regional scales in the East Korean coastal waters were investigated by analysis of the Synthetic Aperture Radar (SAR) images taken by the European Research Satellites ERS-1, ERS-2 and Envisat. More than 500 quick look frames taken in 1991-2003 were examined to detect the frames with clearly surface expressions of oceanic phenomena. 26 ERS-1/2 SAR and 11 Envisat wide swath Advanced SAR (ASAR) frames were selected and obtained from the European Space Agency in a form of the precision high-resolution images. The following oceanic phenomena and processes were evident in the radar imagery through the Korean costal waters: fronts, currents, eddies, internal waves, island and ship wakes, oil pollution, etc. They manifested themselves in the field of sea surface roughness, their scale ranged from several tens meters to about 100 km. The most common morphology of these phenomena was a series of contrast dark or light curvilinear lines and bands. The joint analysis of the discussed SAR images with other satellite and in situ data supported and enhanced our interpretation of SAR signatures.

• Journal of Species Research
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• v.10 no.4
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• pp.364-386
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• 2021

Six species of the family Kelleriidae, including four new species, are recorded from tropical waters of the Asia-Pacific, two of them from Phuket Island, Thailand, one each from Bohol Island, Philippines and Phu Quoc Island, Vietnam, and two from Kosrae Island, Micronesia. A new genus Kelleriella is proposed to accomodate one of these new species (Kelleriella quadridens n. sp.). There are three diagnostic features of the new genus: the terminal segment of antenna is armed with one strong claw and six setae, the armature of the maxilliped endopod is reduced, and the third exopodal segment of leg 4 is armed with four spines and five setae. The other three new species are Kelleria latipes n. sp., Kelleria phuketensis n. sp., and Kelleria robusta n. sp. As diagnostic features of these new species, their caudal rami are about 2.5, 3.2, and 1.72 times longer than wide, respectively, the exopod of leg 5 of them is smooth, without any process, about 1.9, 3.7, and 2.9 times longer than wide, respectively, and armed with one spine plus one seta in Kelleria latipes and Kelleria phuketensis or with 2 setae in Kelleria robusta. Additionally, Kelleria javaensis Mulyadi, 2009 is synonymized with Kelleria regalis Gurney, 1927 and Kelleria grandisetiger Kim, 2006 is synonymized with Kelleria andamanensis Sewell, 1949, and both species are redescribed.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.264-271
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• 2023

The edible jellyfish Rhopilema esculentum occurs in waters throughout northeastern Asia, including in Korea, China, and Japan. In Korean waters, R. esculentum has appeared in two regions (Gangwha and Muan). Based on the appearance of young medusae and coastal distribution records, these two regions may be key R. esculentum breeding sites. In the present study, we investigate and compare the genetic structure of R. esculentum in the two regions using mitochondrial sequences (16S ribosomal RNA and cytochrome c oxidase subunit I). The genetic diversity of the R. esculentum population at Ganghwa exceeded that of the population at Muan. Despite considerable geographic separation (400 km) between the two regions(Gangwha and Muan), our haplotype network suggests that the Gangwha and Muan populations of R. esculentum are related. The simple and monotonous genetic structure of the Muan population shows that R. esculentum emergence is relatively recent. In contrast, the Gangwha population shows evolution. Moreover, jellyfish of the Gangwha population are genetically diverse and remain constant despite environmental fluctuations in the Han River. The Gangwha area is considered to be the old origin of R. esculentum in Korea.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.1
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• pp.9-17
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• 2024

In this study, the seasonal distribution was surveyed using acoustic in the coastal waters around nuclear power plants. Acoustic surveys were conducted in June, September, December 2022, and March 2023 in the coastal waters of Uljin-gun. According to the results of this study, zooplankton were distributed at the depths from 0 m to 50 m in the waters around nuclear power plants. Zooplankton appeared in summer (June), autumn (September), and spring (March). In the survey area, fish were distributed at the depths from 25 m to 190 m, appearing in the summer (June), autumn (September), winter (December) and spring (March). The SV of zooplankton appearing in the survey area ranged from -98.0 dB to -78.0 dB, and it exhibited a one-class in the frequency distribution of SV. The SV of fish appearing in the survey area ranged from -36.0 dB to -35.0 dB and -98.0 dB to -53.0 dB, and it exhibited two-class in the frequency distribution of SV.

• Fisheries and Aquatic Sciences
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• v.3 no.3_4
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• pp.173-179
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• 2000

Recent changes in the coastal sea surface temperatures (SST) in Korea are studied by time series analysis of daily SST data during the last 60 years (1936-1995) at 18 coastal observation stations of the National Fisheries Research and Development Institute. The climate of coastal SST in Korea are rapidly changing in recent years. General trends of coast SST changes in Korea are as follows. The annual averages of SST are increasing. The annual ranges of SST variation are decreasing. The winter SST are increasing while the summer SST have a decreasing tendency. Climatic changes in coastal SST in recent 30 years (1965-1995) are more pronounced than those in the last 60 years (1936-1995). The observed trend of coast SST implies that the climate in Korea shows a tendency to shift from temperate zone to subtropical zone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.1
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• pp.1-10
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• 1972

Studies on the circulation and water masses in the continental shelf break region of the East China Sea are Summerized as follows : 1. The main stream of the Kuroshio flowing north-east near $29^{\circ}N\;Lat\;127^{\circ}E$ tong of the East China Sea in summer is narrow in width. Moving toward east, it becomes twice as wide in Tokora Strait, Japan. 2. In the main stream area of the Kuroshio, the surface Waters in the Upper layer (0-250m) are influenced by the coastal waters of China, and the counter current submerges under the surface water. Therefore, the mixing waters are found in its intermediate layer. 3. Water mass between Amami Island and the continental shelf of the East China Sea consists of main stream water, counter current water, gyration water and mixed water with coastal waters. 4. The maximum velocity of current in this waters was 139cm/sec. The volume transport was estimated approximately as $24.2\;\times\;10^6m^3/sec$. It was less than $33\;\times\;10^6m^3/sec$ in the region between Okinawa and continental shelf of the East China Sea. 5. Surface waters east of $29^{\circ}N\;Lat\;128^{\circ}E$ Long flows toward Amami Island, Okinawa Island, and Hachi Ju San Island, while those west of the region flow toward the Korea-strait, Cheju Island, coastal waters of Kyusyu, and the Pacific Ocean through Tokora Strait. The velocity of the current was estimated approximately as $0.3\~0.5$ miles per hour. 6. The bottom waters in the continental shelf break region flow toward the Korea Strait, Cheju Island and the coastal water of Kyusyu, while that of the continental shelf flows toward the Yellow Sea, 7, The characteristics of the Kuroshio water is changed remarkably by the mixing with the coastal water of China.

• Korean Journal of Ichthyology
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• v.22 no.2
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• pp.126-128
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• 2010

Morphological characters of Heteropriacanthus cruentatus are redescribed in detail based on a single specimen (179.3 mm SL) collected from the coastal waters of Jeju Island, Korea. The species is characterized by dark brown spots scattered on the caudal fin and the soft-rayed portions of the dorsal and anal fins, and 59 pored lateral line scales.

• Journal of Ocean Engineering and Technology
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• v.13 no.4 s.35
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• pp.143-150
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• 1999

Multipurpose fisheries base was conceptually designed to establish marine ranching system in the coastal waters around Tongyoung, southern sea of Korea. Fisheries base for marine ranching system has integrated various facilities which were required for the process of spawning, rearing, training, releasing, monitoring and catching functions. This base has five steel piles for supporting upper structure and systems. Four steel piles are surrounded by circular net pen made by steel wire, they have the function of the protection against fouling for pile and scouring for bottom soil as well as secondary rearing and short stocking. We can use the last pile to moor a ship and access to the base. Principal structure with steel piles is designed by optimization technique considering design external forces in the coastal waters of return period of 50 years. Design optimization Problem is formulated for this base. Optimal design of multipurpose fisheries base is numerically investigated by sequential quadratic programming method.

• Ocean Science Journal
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• v.43 no.2
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• pp.101-106
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• 2008

A single specimen of Albula leptocephalus (55.7 mm SL) was collected from the southern coastal waters of Korea using an aquatic lamp. It is characterized by having a ribbon-like body with a small head and a well-forked caudal fin. Although the general appearance was similar to the leptocephalus of A. vulpes including myomere counts and fin ray counts, the melanophore deposition was different from that of A. vulpes. This leptocephalus specimen was confirmed with A. forsteri using the cytochrome b mtDNA (Cytb) analysis. The genetic distance of Cytb between the present leptocephalus and A. forsteri is 0.006-0.038, which falls into the cutoff point separating Albula species into eight deep lineages including the four valid species. Its genetic characteristic have more similarities to those of Fiji than those of Hawaii and the Northern territory of Australia.