• 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.

• Animal Systematics, Evolution and Diversity
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• v.29 no.4
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• pp.312-315
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• 2013

Sea urchins were collected from waters adjacent to Daludo Island and Mohang harbor in the Yellow Sea, and were identified into Glyptocidaris crenularis A. Agassiz, 1864, of the family Stomopneustidae within the order Stomopneustoida, based on morphological characteristics. This species has two unique morphological characteristics: the ambulacral plate is composed of three primary plates and two demi-plates, and a valve of globiferous pedicellaria consists of with a well-developed long terminal hook and a unique stalk equipped with one to six long lateral processes covering membranes, resembling fins. It is newly recorded in Korea and is described with photographs. This brings the total number of sea urchins reported from the Yellow Sea, Korea, to seven.

• Animal Systematics, Evolution and Diversity
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• v.30 no.2
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• pp.132-136
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• 2014

Five sea cucumbers were collected from Gisamun and Gonghyeonjin of Gangwon-do, in the East Sea, Korea from 27 December 2009 to 14 November 2012. These specimens were classified as Synallactes nozawai Mitsukuri, 1912 belonging to the family Synallactidae of order Aspidochirotida based on morphological characteristics. The family, genus and species are recorded for the first time from Korea. The distinct morphological characteristics of this species are as follows: body flexible, with thin gelatinous body wall; presence of numerous tubercles along dorsal ambulacra table of body wall consisted of three- or four-armed disk and a spire-form pillar. This species usually inhabits the deep sea and is distributed in the Northwest Pacific from northern Japan to Bering Sea.

• Journal of Environmental Impact Assessment
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• v.24 no.4
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• pp.375-385
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• 2015

This study analyzed international case studies on Strategic Environmental Assessment (SEA) follow-up and suggested implications based on the study's findings to aid implementation of SEA follow-up in Korea. SEA requires follow-up in order to identify unforseen adverse effects and enable appropriate remedial action to be taken. Tool kits and methodological framework for effective SEA follow-up are only being researched recently. Based on the study's findings, following implications for implementing SEA follow-up in Korea were drawn. First, the system of carrying out SEA follow-up would be different depending on the PPP topic. During the scoping stage, significant impacts should be identified according to the PPP topic, and thus help determine the indicators to be developed in the later stage. Secondly, responsibility, method, time, intervals and actions from SEA follow-up may vary depending on the target SEA consultation. Thirdly, the indicators of SEA follow-up may be considered together with various environmental standards and current political, social and economic indicators which are a big issue in society. Fourthly, SEA follow-up can be used as an integration system of its target planning and environmental planning. Finally, SEA feedback system should be needed. The result of SEA follow-up should be used for target PPP. These would lead to improvements to the target PPP. If SEA follow up is successfully implemented and actively carried out for domestic PPPs, Korea can be a step closer to realization of sustainable development.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.4
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• pp.1159-1170
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• 2016

This study examines the distribution and taxonomy of sea horses in South Korea, specifically sea horses that were caught in the Southern Sea, centering on Yeosu, South Korea. Specimen collection methods The samples were collected by set net, skimming nets, dragnets, and landing nets on a boat, as well as scuba diving. A total of 128 sea horses belonging to three species were collected. To investigate the exact distribution pattern, the catch per unit effort and the population density per $1,000m^2$ were calculated for each site in the Southern Sea. The result shows the highest catch by set nets was 29 sea horses a day in Site B at Dolsan-eup, Port Impo, and the highest catch by scuba diving was 8 sea horses a day in Site B at Gijang-gun, Busan. The highest population density was 61.2 sea horses in the coast of Gijang-gun, Busan. Genetic information analysis and morphological analysis were performed for determination of species. As a result, four Hippocampus trimaculatus, (flat-faced sea horses), 45 Hippocampus coronatus (Crowned sea horses), and 79 Hippocampus mohnikei (Japanese sea horses) were distinguished.

• Journal of the Society of Naval Architects of Korea
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• v.49 no.2
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• pp.189-195
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• 2012

The ice trials of the first Korean icebreaking research vessel "ARAON" were performed at the Arctic Ocean in July-August 2010. The sea ice concentrations of Arctic Ocean were 4/10 to 10/10 and the range of sea ice thickness was roughly 1.0 to 3.5m. In this research, sea ice thickness characteristics at the old ice floes were determined from results of drill hole and apparent conductivity measurements. Especially we measured apparent conductivity using an electromagnetic induction instrument (EM31-MK2) and estimated the sea ice thickness through the empirical equation from Cold Regions Research & Engineering Laboratory, CRREL. The results of estimated sea ice thickness were compared to drill hole measurement results and then, we suggest the new empirical equation to estimate sea ice thickness of single layer type sea ice during the summer season of Arctic Ocean by curve fitting approach to these data.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.2
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• pp.1-11
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• 2017

In this study, we surveyed the regulations of the Seaplane base and Sea Lane for the Light Sport Aircraft(LSA), and analyzed the water landing/takeoff roll distance of LSA in Korea. Based on the information, we presented the situation of the Sea Lane and the Sea Lane Protection Zone concept, to ensure the Rectangle type Sea Lane and the Omni direction type Sea Lane. We analyzed the availability elements of the safety of Sea Lane for LSA in Korea. A Rectangle type Sea Lane 350 meters long and 40 meters wide, the diameter 350 meters for the An Omni direction type Sea Lane.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.37-40
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• 2007

Satellite altimetric data from 1993 to 2006 are used to study sea level variations in the long tenn in the East Sea. The trend of sea level in the East Sea is rising 4.16 mm/yr and indicate that it rose 5.82 cm in 2006 against to 1993. The South Ses is the fastest in the study areas (4.89 mm/yr, 6.84cm) and the Yellow Sea is 4.10 mm/yr and 5.75cm, respectively. The both of Mokho coast and Ulleung island are minimal sea level in March to May and maximal sea level in September to November. For periods above 20.9days, coherences are found to be higher than 95% confidence level, and the phase differences are near zero.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.165-165
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• 2003

A borehole core ECSDP-102 (about 68.5 m long) has been investigated to get information on paleoenvironmental changes in response to the sea-level fluctuations during the period of late Quaternary. Several AMS $\^$14/C ages show that the core ECSDP-102 recorded the depositional environments of the northern East China Sea for approximately 60 ka. The Yangtze River discharged huge amounts of sediment into the northern East China Sea during the marine isotope stage (MIS) 3. In particular, $\delta$$\^$13/Corg values reveal that the sedimentary environments of the northern East China Sea, which is similar to the Holocene conditions, have taken place three times during the MIS 3. It is supported by the relatively enriched $\delta$$\^$13/Corg values of -23 to -21$\textperthousand$ during the marine settings of MIS 3 that are characterized by the predominance of marine organic matter akin to the Holocene. Furthermore, we investigated the three Holocene sediment cores, ECSDP-101, ECSDP-101 and YMGR-102, taken from the northern East China Sea off the mouth of the Yangtze River and from the southern Yellow Sea, respectively. Our study was focused primarily on the onset of the post-glacial marine transgression and the reconstructing of paleoenvironmental changes in the East China Sea and the Yellow Sea during the Holocene. AMS $\^$14/C ages indicate that the northern East China Sea and the southern Yellow Sea began to have been flooded at about 13.2 ka BP which is in agreement with the initial marine transgression of the central Yellow Sea (core CC-02). $\delta$$\^$18/O and $\delta$$\^$13/C records of benthic foraminifera Ammonia ketienziensis and $\delta$$\^$13/Corg values provide information on paleoenvironmental changes from brackish (estuarine) to modem marine conditions caused by globally rapid sea-level rise since the last deglaciation. Termination 1 (T1) ended at about 9.0-8.7 ka BP in the southern and central Yellow Sea, whereas T1 lasted until about 6.8 ka BP in the northern East China Sea. This time lag between the two seas indicates that the timing of the post-glacial marine transgression seems to have been primarily influenced by the bathymetry. The present marine regimes in the northern East China Sea and the whole Yellow Sea have been contemporaneously established at about 6.0 ka BP. This is strongly supported by remarkably changes in occurrence of benthic foraminiferal assemblages, $\delta$$\^$18/O and $\delta$$\^$13/C compositions of A. ketienziensis, TOC content and $\delta$$\^$13/Corg values. The $\delta$$\^$18/O values of A. ketienziensis show a distinct shift to heavier values of about 1$\textperthousand$ from the northern East China Sea through the southern to central Yellow Sea. The northward shift of $\^$18/O enrichment may reflect gradually decrease of the bottom water temperature in the northern East China Sea and the Yellow Sea.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2004.11a
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• pp.48-48
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• 2004