• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.267-267
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• 2016

Extreme events, such as Winnie(1987), Rusa(2002), Maemi(2003) at sea-side urban area, resulted not only economic losses but also life losses. The Korean sea-side characterisitcs are so complicated thar the prediction of sea level rise makes difficult. Geomophologically, Korean pennisula sits on the rim of the Pacific mantle so the sea level is sensitive to the surges due to earth quake, typoon and abnormal climate changes. These environmetns require closer investigation for the preparing the inundatioin due to the sea level rise with customized prediction for local basin. The goal of this research is provide the information of inundation risk so the sea side urban basin could be more safe from the natural water disastesr.

• Economic and Environmental Geology
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• v.38 no.6 s.175
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• pp.643-656
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• 2005

The East Sea, a marginal sea or back-arc basin, consists of Japan Basin, Yamato Basin, and Ulleung Basin and is surrounded by the Pacific Plate and Philippine Sea Plate. Ulleung Basin locates in the southwestern part of the East Sea and shows the depth of 1,500 m in average and 2,500 m in maximum, connecting to the Japan Basin along 2,000 m contour. The slope of the seafloor is greater in the western side of the basin than in the southern and the eastern side. The crustal thickness of the Ulleung Basin from the OBS tends to get thicker toward the north and the west side and the sediment thickness of the Ulleung Basin is getting thicker toward the southeast side and reaches up to 12 km. The crustal type of the Ulleung Basin was variously suggested as like as a rifted continental crust, an extended continental crust, and an incipient oceanic trust. The origin of the crustal formation and the Ulleung Basin, however, is still controversial. Based on the bathymetry and gravtiy anomaly data for this study, the axis of the Ulleung Basin shows that the basin develops along the axis trending NW-SE direction and reveals a general symmetry of the bathymetry. And also the free-air gravity anomalies show a very similar pattern to the bathymetry of the basin. The sediment thickness is relatively thicker in the southeastern side of the basin than in the northwestern side. Although the crustal age of the Ulleung Basin is supposed to be younger than them of the Japan Basin and the Yamato Basin, the free-air gravity anomalies of the Ulleung Basin ranging -40 to 50 mGals are lower than the other basins, which suggests that the densities of crust and sediment of the Ulleng Basin are lower than the Japan Basin and the Yamato Basin.

• Journal of Environmental Science International
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• v.20 no.7
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• pp.829-837
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• 2011

A study on the grain size change, sedimentary facies and age indicator of volcanic tephra was analysis through four cores (P1 ~ P4) at the Ulleung Basin in the East Sea of Korea. The two cores (P1 and P2) were collected in the northeastern side of the Ulleung Basin (about 2,000 m in water depth), while the other two cores (P3 and P4) with the water depth of about 1,500 m and 1,700 m, respectively, were collected from the continental slope of the southwestern and western side of the Ulleung Basin. Four sedimentary facies and eight sedimentary subfacies were identified. The four facies were massive sand, bioturbated mud, homogeneous mud, and laminated mud. The eight subfacies were further divided as pumiceous ash massive sand, scorieaous massive sand, plain bioturbated mud, pyrite filamented bioturbated mud, distinctly laminated mud, indistinctly laminated mud, thinly laminated mud and homogeneous mud. The homogeneous mud was not found in the core of P3 which is located in the western side of Ulleung Basin (close to the Korean coast). In the case of laminated mud facies, the thinly laminated mud facies was dominated in the lower part of core sequences of the Ulleung Basin (P1 and P2), while the indistinctly laminated mud were overally distributed in the core sequences from the continental slope of Ulleung Basin. The Tephra layers from the core sequences of central Ulleung Basin were more dominated and distinctive than those from the core sequences of continental slope. This is related to the distance from the volcanic source and the amount of sediment supply. The core locations of Ulleung-Oki Tephra layers in the central Ulleung Basin were in the upper part of core sequences, while those in the continental slope were in the lower part of core sequences. This is indicated that the amounts of sediment supply in the continental slope after the Ulleung-Oki eruption were very high and different sedimentary environment between upper and lower of Tephra layer.

• 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.

• Journal of the Korean Geographical Society
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• v.33 no.2
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• pp.143-163
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• 1998

In order to clarify the depositional environment and sea-level change at Ilsan area including Gawaji and Saemal valley plains, which is located at the right side in downstream of the Han River, boring data, radiocabon dating and diatom analysis were comprehensively investigated. As a result, the palaeogeographies fo this area altered by the transgressions and regressions after 7,000 y. BP could be restored. The high tide sea-level(mean high water level of spring tide) was arrived ca. 7,000y. BP at the valley plain and risen to ca. 5.5m at ca. 5000y. BP. Since then, the sea-level was kept up the same level to ca. 3,200 BP. The descended sea-level to ca. 2,300 BP was risen up to ca. 5.8m in ca. 1,800 y. BP. It is presumed that such a sea-level change as well as the different sediments in quantity supplied from the river basin of the valley plain could be effected to change diversely the depositional environment of the study area and eventually to the prehistoric human life.

• 한국해양학회지
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• v.30 no.6
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• pp.537-542
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• 1995

Effect of Shantung Peninsula on the development of mean upwind flow in the Yellow Sea in winter is analysed using a simple model. The results indicate that the disturbances generated by the Shantung Peninsula have a scale much larger than the basin scale whereas disturbances, if any, generated similarly on the other side of the trough has much smaller scale. The effect of Shantung Peninsula thus dominates over the whole basin and deflects westward the otherwise northward upwind flow.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.6
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• pp.311-322
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• 1988

Application of the simple buoyancy adjustment model, similar to Davey's (1983), indicates that buoyancies imposed locally or from outside of the basin are the major factor of the Japan Sea circulation. Within the context of the model considered, the relatively strong SW gradient of temperature, and corresponding western boundary current, in the SW region is due to the beta-effect. Kelvin waves make the western side colder and the eastern side warmer. Buoyancy input (presumably by fresh water discharge) in the NW region, so far neglected, plays an important role in strengthening the NKCC (North Korea Cold Current) and suppressing the EKWC (East Korea Warm Current) thereby breaking the conventional branching system of the Tsushima Warm Current.

• The Korean Journal of Petroleum Geology
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• v.14 no.1
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• pp.53-62
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• 2008

Seismic interpretation was carried out based on biostratigraphy of Fukue-1 well in Japan side of the Domi Basin and compared with the Cheju Basin and Tertiary basins in north-west Kyushu. East China Sea Basin including Domi Basin began to develope in the latest Cretaceous$\sim$Paleocene related to rifting. The basin was filled with a thick package of syn-rift sediments during Paleocene to Oligocene and was under post-rift stage effected by transtenssion during Miocene. Previous studies suggest that the basin had been mostly filled with Miocene formation (>3 km), but the Miocene formation is interpreted to be comparatively thin in this study. The thickness of the Miocene formation varies from tens of meters to hundreds of meters and become thicker to the south-west of Cheju Basin. The index taxa of the Oligocene$\sim$Eocene nannofossils and dinoflagellates found in the Cheju Basin and Tertiary basins in north-west Kyushu also corroborate the result of this study.

• Proceedings of the KSRS Conference
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• v.1
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• pp.352-355
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• 2006

In this study, the seasonal and inter-annual variation of sea surface current in the Gulf of Thailand were revealed through the use of WOD temperature and salinity data and monthly sea surface dynamic heights (SSDH) from TOPEX/Poseidon and ERS-2 altimetry data during 1995-2001. The mean dynamic height and mean geostrohic current were derived from the climatological data while SSDH data gave monthly dynamic heights and their geopstrophic currents. The mean geostrophic current showed strong southward and westward flow of South China Sea water along the gulf entrance. Counterclockwise eddy in the inner gulf and the western side of the gulf entrance associated with upwelling in the area. Seasonal geostrophic currents show basin-wide counterclockwise circulation during the southwest monsoon season and clockwise circulation during the northeast monsoon season. Upwelling was enhanced during the southwest monsoon season. The circulation patterns varied seasonally and inter-annually probably due to the variation in wind regime. And finally we found that congregation, spawning, and migration routes of short-bodied mackerel conform well with coastal upwelling and surface circulation in the gulf.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• v.25 no.1
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• pp.57-81
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• 1997

Numerical prediction of nocturnal thermal high in summer of the 1995 near Taegu city located in a basin has been carried out by a non-hydrostatic numerical model over complex terrain through one-way double nesting technique in the Z following coordinate system. Under the prevailing westerly winds, vertical turbulent fluxes of momentum and heat over mountains for daytime hours are quite strong with a large magnitude of more than $120W/\textrm{m}^2$, but a small one of $5W/\textrm{m}^2$ at the surface of the basin. Convective boundary layer (CBL) is developed with a thickness of about 600m over the ground in the lee side of Mt. Hyungje, and extends to the edge of inland at the interface of land sea in the east. Sensible heat flux near the surface of the top of the mountain is $50W/\textrm{m}^2$, but its flux in the basin is almost zero. Convergence of sensible heat flux occurs from the ground surface toward the atmosphere in the lower layer, causing the layer over the mountain to be warmed up, but no convergance of the flux over the basin results from the significant mixing of air within the CBL. As horizontal transport of sensible heat flux from the top of the mountain toward over the basin results in the continuous accumulation of heat with time, enhancing air temperature at the surface of the basin, especially Taegu city to be higher than $39.3^{\circ}C$. Since latent heat fluxes are $270W/\textrm{m}^2$ near the top of the mountain and $300W/\textrm{m}^2$ along the slope of the mountain and the basin, evaporation of water vapor from the surface of the basin is much higher than one from the mountain and then, horizontal transport of latent heat flux is from the basin toward the mountain, showing relative humidity of 65 to 75% over the mountain to be much greater than 50% to 55% in the basin. At night, sensible heat fluxes have negative values of $-120W/\textrm{m}^2$ along the slope near the top of the mountain and $-50W/\textrm{m}^2$ at the surface of the basin, which indicate gain of heat from the lower atmosphere. Nighttime radiative cooling produces a shallow nocturnal surface inversion layer with a thickness of about 100m, which is much lower than common surface inversion layer, and lifts extremely heated air masses for daytime hours, namely, a warm pool of $34^{\circ}C$ to be isolated over the ground surface in the basin. As heat transfer from the warm pool in the lower atmosphere toward the ground of the basin occurs, the air near the surface of the basin does not much cool down, resulting in the persistence of high temperature at night, called nocturnal thermal high or tropical night. High relative humidity of 75% is found at the surface of the basin under the moderate wind, while slightly low relative humidity of 60% is along the eastern slope of the high mountain, due to adiabatic heating by the srong downslope wind. Air temperature near the surface of the basin with high moisture in the evening does not get lower than that during the day and the high temperature produces nocturnal warming situation.