• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.1 s.24
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• pp.23-32
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• 2006

This study was conducted to find out the effects of meterological factors on oceanic conditions when cold and dry continental air mass passes through the western sea of Korea The change of ocean conditions during the winter season were more obvious in coastal area than open sea And sea surface temperature (SST) during February is lower by $3^{\circ}C$ than December but in coastal area SST dropped by $3^{\circ}C$. As for the salinity, there was not much difference between areas except southern area of Mokpo. In the coastal regions, air temperature(AT) and SST showed a positive correlation; as the air temperature goes up with the increase of SST and when the former goes down the latter decrease. SST of open sea seems to be changed by latent (Qe) and sensible heat (Qs), when the open sea lose its heat by Qe and Qs then SST goes down And when they get the heat then the SST goes up. 1here was a positive correlation between the AT of the coastal region and sea surface salinity (SSS), when the AT goes up then SSS increase and when the former goes down the latter decrease. Precipitation during the summer seasons (June$\sim$September) appeared to the more closely related with salinity of February of the following year than those of October and December.

• Korean Journal of Plant Taxonomy
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• v.39 no.4
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• pp.264-276
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• 2009

To elucidate the distribution of halophytes in Korea, we surveyed 95 coastal salt marsh and sand dune areas. As a result, 62 halophytes of 57 species, 4 varieties and 1 form belonging to 44 genera and 21 families were recorded from coastal regions and islands of South Korea. Of these, 33 taxa were plants growing on sand dunes and the other 29 in salt marsh. Fifty eight taxa were found on the west coast, which was surveyed at 61 areas. The most common species among them were Suaeda glauca (Bunge) Bunge, Suaeda japonica Makino, Phragmites communis Trin., Zoysia sinica Hance, Carex scabrifolia Steud. in salt marsh, and Salsola komarrovii Iljin, Lathyrus japonicus Willd., Limonium tetragonum (Thunb.) A.A. Bulloc, Calystegia soldanella Roem. & Schult. on sand dunes. On the other hand, only 45 taxa were found on the southern coast, surveyed at 15 areas. On the east coast, surveyed at 13 areas, 44 taxa were found. The most common species were Salsola komarrovii Iljin, Lathyrus japonicus Willd., Calystegia soldanella Roem. & Schult., on sand dunes and Linaria japonica Miq., which on the Korean peninsula is found only on the east coast. On Jeju Island, surveyed at 6 areas, 30 taxa of halophytes were found. Canavalia lineata (Thunb.) DC. is found in Korea only on Jeju Island. About half of the Korean halophytes were members of three families (Chenopodiaceae: 12 species, Poaceae: 12 species and Asteraceae: 7 species).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.27 no.3
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• pp.158-172
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• 2022

The distribution of seabirds was investigated in 24-34 major coastal wetlands in Korea from 2015 to 2019. During the study period, seven orders, 16 families, and 111 species were observed, and the largest number of species (51-89 species) was recorded in 2018. 92,821-265,783 individuals per year were observed with the largest number in 2018. The largest number of species (55-72 species) was observed in the southern sites of Jeollado, and the largest number of individuals (annual average of 62,542 individuals) was found in Chungcheong regions. The largest number of seabird species (68 species) was observed at the Suncheon Bay site in 2016, and the largest number of individuals (95,399 individuals) was observed at Biin and Jangan sites in 2018. In terms of the habitat type of seabirds, at the family level, shorebirds appeared most frequently with an average of 38%, followed by waterfowl, wading birds, seabirds, and raptors. With regard to legally protected species, eight protected marine species, 19 endangered wildlife species (Level I: six species, Level II: 13 species), and twelve natural monument species were observed. Overall, there was a significant difference in the number of species and individuals of seabirds in the Korean coastal wetlands during the research period. This suggests the importance of conducting systematic and continuous seabird surveys and developing a conservation policy considering habitat characteristics.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.35 no.4
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• pp.75-83
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• 2023

Apart from implementing hardware solutions like raising the crest freeboard of coastal structures to efficiently counter wave-overtopping, there is a simultaneous requirement for software-driven disaster mitigation strategies. These tactics involve the swift and accurate dissemination of wave-overtopping information to the inland regions of coastal zones, enabling the regulation of evacuation procedures and movement. In this study, a method was proposed to estimate wave-overtopping by utilizing the temporal variation of wave heights exceeding the structure's crown level, with the aim of developing an on-site wave measurement system for providing wave-overtopping information in the field. Laboratory model experiments were conducted on vertical seawall structures to measure wave-overtopping volumes and wave runup heights under different wave conditions and structural freeboard variations. By assuming that the velocity of water inundation on the top of the structure during wave-overtopping events is equivalent to the long-wave velocity, an overtopping discharge coefficient was introduced. This coefficient was utilized to estimate the rate of wave-overtopping based on the temporal changes in wave runup heights measured at the top of the structure. Upon reasonably calculating the overtopping discharge coefficient, it was verified that the estimation of wave-overtopping could be achieved solely based on the wave runup heights.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.2
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• pp.68-77
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• 2002

We investigated the outbreak, maintenance, and decline of the red tide dominated by C. polykrikoides in the coastal waters off Southern Korea from August to October, 2000, by combining field data and NOAA satellite images. In general, the C. polykrikoides blooms, which have occured annually in Korean coastal waters from 1995 to 1999, initiate between late August and early September around Narodo Island and expand to the whole area of the southern coast. However, initiation and short-term change of the bloom of 2000 were quite different from the pattern observed previously. In mid-August, thermal fronts in sea surface temperature(SST) were formed: 1) between the Tsushima Warm Current Water (TWCW) and the Southern Korean Coastal Waters (SKCW), 2) between the jindo cold water mass and the southwestern coastal waters, and 3) between the upwelled cold waters in the southeast coast and the offshore warm waters. Free-living cells of C. polykrikoides were concentrated in these frontal regions. In late August, the thermal front TWCW-SKCW approached the mouth of Yeosuhae Bay where Seomjin River water and anthropogenic pollutants from the Industrial Complex of Gwangyang Bay are discharged. In the blooms of 2000 initiated in Yeosuhae Bay in late August, the dominant species, C. polykrikoides, co-occured with Alexandrum tamarense, Gymnodinium mikimotoi, Skeletonema coastatum, and Chaetoceros spp. Two typhoons, 'Prapiroon' and 'Saomai' during and the C. polykrikoides bloom probably affected the abundance of this species. After the former typhoon passed the Korean Peninsula, cell growth of C. polykrikoides was maximal, but after the latter typhoon, the C. polykrikoides bloom disappeared (20 September). On 5 October, the blooms dominated by C. polykrikoides broke out within the coastal waters of Jinhae Bay and Hansan-Keoje Bay. NOAA satellite images showed that the isothermal line of 22$^{\circ}C$ extended into Jinhae Bay. In this bloom, C. polykrikoides also occurred simultaneously with Akashiwo sanguinea(=Gym-nodinium sangunium), a common red tide-forming dinoflagellate species in fall and winter in these coastal bays.

• Journal of the Korean Geographical Society
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• v.31 no.3
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• pp.469-488
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• 1996

The defining of weather forecasting regions is possible. since the representativeness of regional weather can by reasonably clarified in terms of weather entropy and the use of information ratio. In this paper, the weather entropy and information ratio were derived numerially from using the information theory. The typical weather characteristics were clarified and defined in the homogeneous weather forecasting regions of the southern parts of Korea. The data used for this study are the daily precipitation and cloudiness during the recent five years (1990-1994) at 42 stations in southern parts of Korea. It is divided into four classes of fine, clear, cloudy and rainy. The results are summarized as follows: 1. The maximum value of weather entropy in study area is 2.009 vits in Yosu in July, and the minimum one is 1.624 bits in Kohung in October. The mean value of weather entropy is maximal in July, on the other hand, minimal in October during four season. The less the value of entropy is, the stabler the weather is. While the bigger the value of entropy is, the more changeable the weather is. 2. The deviation from mean value of weather entropy in southern parts of Korea, with the positive and the negative parts, shows remarkably the distributional tendency of the east (positive) and the west (negative) in January but of the south (positive) and the north (negative) in July. It also clearly shows the distributional tendency of the east (postive) and the west(negative) in the coastal region in April, and of X-type (southern west and northern east: negative) in Chiri Mt. in October. 3. In southern parts, the average information ratio maximaly appear 0.618 in Taegu area in July, whereas minimally 0.550 in Kwangju in October. Particularly the average information ratio of Pusan area is the greatest in April, but the smallest in October. And in Taegu, Kwangju, and Kunsan, it is the greatest in April, January, and July, but the smallest in Jyly, July, and pril. 4.The narrowest appreance of weather representativeness is in July when the Kwangju is the center of the weather forecasting. But the broadest one is in April when Taegu is the center of weather forecasting. 5. The defining of weather forecasting regions in terms of the difference of information ratio most broadly shows up in July in Pusan including the whole Honam area and the southern parts of Youngnam when the Pusan-Taegu is the basis of the application of information ratio. Meanwhile, it appears most broadly in January in Taegu including the whole southern parts except southern coastal area.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.171-178
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• 2013

This paper presents the Part 1 of the Questionnaire Survey on Marine Safety and VTS in the Philippine Coastal Waters. This part deals with respondents profiles; experiences onboard and ashore; familiar areas; and their subjective perception of marine risks- by factors and by areas. The subjects are chosen from different regions nationwide with connection and/or with maritime background. There are 202 responses returned and these are put into a database for analysis made through Excel programs and statistics references. The result of the nationwide responses show that 97 % of respondents have shipboard experiences onboard of different ships' types and sizes; and 88 % are directly involved in the navigation of ships. Risk Perception levels - by factors and by familiar areas - show a higher risk degree in the 3rd level ('Sometimes Increases Risks') and 4th level ('Often Increases Risk') in each respondents' response indices. The study finds that the most risky factor is the "Violation of Rules and Regulations" which has a high risk at 5th level (Very Often Increases Risk), and for the over-all familiar areas, the Manila Bay area (NCR region) garners the most risky perception, also, at the 5th level. It is, therefore, recommended by this paper to conduct a comprehensive review of the rules and regulations viable in each locality; strengthening the maritime traffic systems, structures and educating the stake-holders specifically in Manila Bay area and other busy waterways of the country. The ultimate goal of this paper is to gather information, analyze these data and develop a set of tools and techniques to be utilized as a guide in the improvement and development of maritime traffic safety in the country.

• Journal of Korea Water Resources Association
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• v.45 no.8
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• pp.743-753
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• 2012

AWS data can be used effectively to understand the rainfall characteristics in Korea. In spite of this advantage, AWS data have been used restrictively in flood control analysis and the study on water use analysis such as water balance assessment is very insufficient. In this study, AWS data are used to analyze spatial rainfall characteristics quantitatively and water balance assessment is performed based on AWS data. Water balance assessment is carried out from year 2002 to year 2010 considering water supply networks in Korea. The analysis shows that year 2009 is the driest year during 9 years (2002~2010) and the regions with low level water supply reliability are concentrated in the west coast of Jeonnam and the upper region of the Nakdong River. As a result, the regions that have a lack of available water resources such as the coastal and insular areas are vulnerable to droughts. Therefore, regional water supply and management plans are urgently needed. Additionally, AWS data, which consider rainfall characteristics of the coastal and insular areas, can be useful in water balance assessment.

• Journal of the Korean association of regional geographers
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• v.19 no.4
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• pp.600-614
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• 2013

This study aims to examine spatially-detailed changes and projection of subtropical climate zones based on the modified K$\ddot{o}$ppen-Trewartha's climate classification and extreme temperature indices using $1km{\times}1km$ high resolution RCP 4.5 and RCP 8.5 climate change scenarios based on PRIDE model over the Republic of Korea. Subtropical climate zones currently located along the southern coastal region. Future subtropical climate zones would be pushed northwards expanding to the western and the eastern coastal regions as well as some metropolitan areas. For both scenarios, the frequency of cold-related extreme temperatures projects to be reduced while the frequency of hot-related ones projects to be increased. Especially, hot days with $33^{\circ}C$ or higher temperature projects to occur more than 30 days over the most of regions except for some mountain areas with high altitudes during the period of 2070~2100. This study might provide essential information to make climate change adaptation processes be enhanced.

• Korean Journal of Environment and Ecology
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• v.31 no.5
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• pp.455-460
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• 2017

Since a new (unrecorded) species was reported in 2016, a total of four sea snake species are currently listed in Korean waters. Although the possibility of year-round inhabitation of sea snakes in Korean waters has increased due to climate change, the related studies are scarce because of the lack of human resources and available equipment. We placed posters and banners requesting voluntary information on sea snakes in coastal regions and Jeju Island to obtain information on sea snake distributions in the coasts of South Korea and possible specimens through volunteer activities. As a result, we received total 45 reliable reports, including photographs or video, between March 2013 and December 2016. Eighteen reports on three sea snake species and thirteen capture cases of two species were submitted from Jeju Island and southern coastal regions of Korea mostly between August and November. There were twenty-seven false reports including seven cases of terrestrial snakes, eighteen fishes, and one each of invertebrate and inanimate material. Based on the results, we proposed the effective way of sea snake surveys using volunteers.