• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.4
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• pp.369-379
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• 2003

Analysis of high-resolution seismic profiles and sediment data from the southeastern continental shelf of Korea reveals that the late Quaternary deposits consist of a set of lowstand (LST), transgressive (TST), and highstand systems tracts (HST) that corresponds to the sea-level change after the Last Glacial Maximum. LST (Unit I) above the sequence boundary consists of sandy mud or muddy sand deposited during the last glacial period and is confined to the shelf margin and trough region. TST (Unit II) between transgressive surface and maximum flooding surface consists of sandy sediments deposited during the postglacial transgression (15,000-6,000 yr BP). Although TST is widely distributed on the shelf, it is much thinner than LST and HST. On the basis of distribution pattern, TST can be divided into three sub-units: early TST (Unit IIa) on the shelf margin, middle TST (Unit IIb) on the mid-shelf, and late TST (Unit IIc) on the inner shelf, respectively. These are characterized by a backstepping depositional arrangement. HST(Unit III) above the maximum flooding surface is composed of the fine-grained sediments deposited during the last 6000 yrs when sea level was close to the present level and its distribution is restricted to the inner shelf along the coast.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.4
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• pp.134-143
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• 2016

This study analyzed the characteristics of emergy inputs from environmental sources that are essential in maintaining ecological processes and providing ecosystems services of the tidal flat ecosystems in Korea. Environmental sources provided a total of $4.98{\times}10^{21}sej/yr$ of emergy to the tidal flats of Korea. The emergy inputs from environmental sources were worth 1,141 billion ￦/yr. This is the value of environmental conditions that are the basis of ecosystem services provided by the tidal flat ecosystems. The emergy input per hectare to regional tidal flats decreased along the coastline from northwest to southeast, with the highest input in the Incheon-Gyeonggi area in the central western part of the Korean coast and the lowest input in the Busan area in the southeastern end. This reflects the general distribution pattern of the magnitude of tidal ranges along the Korean coast. There was no a clear-cut relationship between emergy inputs per unit area and fishery production(expressed in emergy quantity) per unit area. However, tidal flats in the west coast with higher emery inputs per unit area produced more fishery products than those in the south coast with lower emergy inputs, suggesting a possibility that the emergy inputs could be used for the rapid evaluation and comparison of the potential for ecosystem service provision by individual tidal flats.

• Journal of the korean society of oceanography
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• v.34 no.1
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• pp.1-21
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• 1999

A two-layer quasi-geostrophic numerical model is used to investigate the temporal variability of the East Korea Warm Current (EKWC), especially the separation from the Korean coast and the generation of warm eddies. An attention is given on the active role of the nonlinear boundary layer process. For this, an idealized flat bottom model of the East Sea is forced with the annual mean wind curl and with the inflow-outflow specified at the Korea (Tsushima) and Tsugaru Straits. Two types of separation mechanisms are identified. The first one is influenced by the westward movement of the recirculating leg of the EKWC (externally driven separation),the second one is solely driven by the boundary layer dynamics (internally driven separation). However, these two processes are not independent, and usually coexist. It is hypothesized that 'internally driven separation' arises as the result of relative vorticity production at the wall, its subsequent advection via the EKWC, and its accumulation up to a critical level characterized by the separation of the boundary flow from the coast. It is found that the sharp southeastern corner of the Korean peninsula provides a favorable condition for the accumulation of relative vorticity. The separation of the EKWC usually accompanies the generation of a warm eddy with a diameter of about 120 km. The warm eddy has a typical layer-averaged velocity of 0.3 m/s and its lifespan is up to a year. In general, the characteristics of the simulated warm eddy are compatible with observations. A conclusion is therefore drawn that the variability of the EKWC is at least partially self-excited, not being influenced by any sources of perturbation in the forcing field, and that the likely source of the variability is the barotropic instability although the extent of contribution from the baroclinic instability remains unknown. The effects of the seasonal wind curl and inflow-outflow strength are also investigated.

• Journal of Environmental Science International
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• v.20 no.2
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• pp.275-289
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• 2011

In order to clarify the relation between sea breeze penetration and Planetary Boundary Layer development in southeastern part of the Korean Peninsula, several numerical assessments were carried out using atmospheric numerical model WRF(Weather Research and Forecasting). Compared with onset time of sea breeze at eastern coast area(Uljin), the time at southern coast region(Masan) with complex costal line tend to delay for several hours. The penetration patterns of sea breeze between two coastal regions are some different due to the shape of their coastal line and back ground topography. Intensified valley wind due to high topography of lee side of Uljin can help penetration of sea breeze at early time. So penetration of sea breeze at early time often prevent PBL to develop at Uljin and lower PBL height last for a day time. But because of late penetration of sea breeze at Masna, PBL Height dramatically decrease after 1500LST. The distribution of front genesis function based on the heat and momentum variation are explained obviously the sea breeze penetration patterns and agreed well with the PBL height distribution.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.5
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• pp.380-390
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• 2009

This study was conducted as a part of investigating pre-reclamation shorelines from aerial photographs to estimate coastal land area at reclaimed lands (Anjeong industrial complex, Myeongji residental complex, and Noksan industrial complex), southeastern coast of Korea. To assess how the shorelines were suitable for the calculation of coastal lands, we constructed shoreline change data. Secondary ground control points were used to accomplish triangulation for old aerial photographs. Two kinds of shorelines were mapped; one was the shoreline based on approximately highest high water level (AHHWL) and the other was the high water line based on wet/dry signiture. These shorelines were consistent at artificial coast. Shoreline change data were built with a variety of levels of error due to detailed differences in the photograph scale, quality of image, type of ground control point and type of shoreline. Thus assessment of the pre-reclamation shorelines at the level of qualitative analysis for the trend of shoreline changes was satisfactory. Most of shoreline changes before reclamation in this study were associated with coastal development. Investigation of shoreline attributes in relation to aerial photographs allowed us to understand the shoreline changes.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.6
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• pp.481-492
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• 2009

The characteristic of cold water by upwelling in the southeast of the Korean Peninsula and the effect of sea breeze in this region are investigated. The coastal upwelling around the southeast coast of the Korea Peninsula is analyzed by using Coastal Oceanographic Data statistical analyses for 5 years were carried out. The period of an cold water event, on the average, was observed southwesterly wind events. The analysis suggests that strong and persistent southwesterly winds in period of an cold water play an important role of bring the moisture to the surface, generating persistent cyclone as jangma. In order to investigate the effect of cold water on sea breeze, we considered two case. First, Exp. 1 is not occurred coastal upwelling on sea breeze. Second, Exp. 2 is occurred cold water on sea breeze. Two experiments were completed separately to the effects of cold water by upwelling. The results show the sea breeze is stronger in Exp. 2, when the cold water occurs, and weaker in Exp. 1, when there is no cold water. In order to verify the effect of the sea breeze on the cold water by upwelling, on the intensification and change of direction of the prevailing wind, the sea breeze effectively intensify cold water condition.

• 한국해양학회지
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• v.26 no.3
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• pp.262-277
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• 1991

Hydrographic data taken at stations spaced 8-16 nautical miles in the Cheju Strait and the southeastern part of the Yellow Sea in June 1980 and August 1981 show for the first time that oceanic water of high temperature and high salinity exists within 20 km from the northern and western coast of Cheju-Do. It is confirmed that the low salinity trough in the sea around Cheju-Do originates from the river plume on the Yantze Bank. The salinity trough separates the high temperature and high salinity water around Cheju-Do from the surface water of the Yellow Sea and below the seasonal thermocline this distance water meets the Yellow Sea Cold Water forming a thermal front. The Yellow Sea Cold Water seems to spread southward along the Yantze Bank centered at the isobath of 70 m. Its characteristics also appear in the northern part of the Cheju Strait. these complex structures contradict the yellow Sea Warm current suggested by Uda 1934), which is supposed to flow northward into the Yellow Sea along the western coast of Korea. Our data show that dense hydrographic surveys in space and time are prerequisite to understand the circulation around Cheju-Do.

• Asian Journal of Atmospheric Environment
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• v.5 no.4
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• pp.216-227
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• 2011

A Sea breeze front (SBF) appears clear particularly if there is opposing wind, and the convergence zone along a SBF affects air quality in coastal areas. This study analyzes features of SBF separation in the presence of an opposing flow in the southeastern coastal area of Korea Peninsula. Using a Regional Atmospheric Modeling System (RAMS) numerical simulation and an opposing flow, two types of SBF were observed at Masan coastal area of Korea. In one, the SBF penetrated inland despite of the opposing flow at Jinhae (1100 LST), Wondong (1700 LST), Saenglim (1700 LST), and Miryang (1700 LST). In the other, the SBF remained on the coastline along with Jinhae (1100 LST), Masan (1400 LST), Jinbuk (1400 LST), and Gaecheon (1700 LST), because the inflow of the sea breeze was not sufficient to penetrate inland against the opposing flow. This study shows that SBFs are affected by the formation of an opposing flow, as well as the inflows of a sea breeze and the opposing flow.

• Conservation and Restoration of Cultural Heritage
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• v.1 no.1
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• pp.29-37
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• 2012

The West Stone Pagoda at Gameunsaji Temple Site constructed in the 7th century is mainly composed of dark grey dacitic tuff bearing small numerous dioritic xenoliths. These xenoliths resulted in small holes due to differential weathering process from the host rocks. Physical strength of the pagoda was decreased due to weathering and damage caused by petrological, biological and coastal environmental factors. The southeastern part of the pagoda was extremely deteriorated that the rock surface showed exfoliation, fracture, open cavity, granular decomposition of minerals and salt crystallization by seawater spray from the eastern coast. The stone blocks were intersected by numerous cracks and contaminated by subsequent material such as cement mortar and iron plates. Also, the pagoda was colonized by algae, fungi, lichen and bryophytes on the roof rock surface and the gaps between the blocks. As a result of ultrasonic test, the rock materials fell under Highly Weathered Grade (HW) or Completely Weathered Grade (CW). Thus, conservational intervention is essentially required to prevent further weakening of the rock materials.

• ALGAE
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• v.29 no.4
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• pp.267-277
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• 2014

Green tides occur every year in the Yellow Sea (YS), and numerous investigations are proceeding on various aspects of the phenomenon. We have identified bloom-forming species collected from diverse locations in the YS using morphological traits and the chloroplast gene for the large subunit of ribulose-1,5-bisphosphate carboxylase (rbcL). Morphological and rbcL sequence data analyses characterized the blooming species on both sides of the YS as belonging to the Ulva linza-procera-prolifera (LPP) complex clade or U. prolifera of earlier reports. However, U. procera within the LPP complex must be regarded as synonym of U. linza. Moreover, U. prolifera in free-floating samples collected from the Qingdao coast in 2009 was clearly in a distinct clade from that of the blooming species. Therefore, U. linza is the main green tide alga in the YS and has the procera-morphology. The green drift mats in the southeastern part of the YS (southwest sea of Korea) consisted predominantly of U. linza and rarely of U. compressa or U. prolifera.