• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.1
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• pp.55-64
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• 2008

In these days, not only many peoples were killed or wounded by seismic sea waves in Indonesia, but also our country is influenced by disasters such as tsunami and earthquake happened in sea areas adjacent to japan. The precaution against disaster and the rapid communication of disaster informations have become important. In order to minimize and prevent citizens' properties and lives from the loss or the damage by natural calamities suas storms, earthquakes and typhoons, the establishment of communication network for rapid information transmission and the development of system for preventing citizens from disasters should be performed.

• Ocean and Polar Research
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• v.30 no.3
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• pp.325-334
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• 2008

A biogeochemical model was used to estimate air-sea $CO_2$ exchange over the East China Sea. Since fresh water discharge from the Changjiang River and relevant chemistry were not considered in the employed model, we were not able to produce accurate results around the Changjiang River mouth. This factor aside, the model showed that the East China Sea, away from the Changjiang River mouth, takes approximately $1.5{\sim}2\;mole\;m^{-2}yr^{-1}$ of $CO_2$ from the atmosphere. The model also showed that biological factors modify the air-sea $CO_2$ flux by only a few percent when we assumed that biological activity increased two-fold. Therefore, we can argue that the biological effect is not strong enough over this area within the framework of the current phosphate-based biological model. Compared to the preindustrial era, in 1995 the East China Sea absorbed $0.4{\sim}0.8\;mole\;m^{-2}yr^{-1}$ more $CO_2$. If warming of the sea surface is considered, in addition to the increase in atmospheric $CO_2$ concentration, by 2045 the East China Sea would absorb $0.2{\sim}0.4\;mole\;m^{-2}yr^{-1}$ less $CO_2$ compared to the non-warming case.

• Ocean and Polar Research
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• v.30 no.3
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• pp.335-345
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• 2008

In order to study spatial variabilities and major controlling factors, we measured fugacity of $CO_2(fCO_2)$, temperature, salinity and nutrients in surface waters of the North Pacific($7^{\circ}30'{\sim}33^{\circ}15'N$, $123^{\circ}56'E{\sim}164^{\circ}24'W$) between September$\sim$October 2007. The North Pacific and the marginal sea were distinguished by $fCO_2$ distribution as well as unique characteristics of temperature and salinity. There was a distinct diurnal SST variation in the tropical North Pacific area, and surface $fCO_2$ coincidently showed diurnal variation. In the North Pacific area, surface $fCO_2$ was mainly controlled by temperature, while in the marginal sea area it was primarily dependent on alkalinity and dissolved inorganic carbon concentrations. Air-sea $CO_2$ flux showed a large spatial variation, with a range of $-6.10{\sim}5.06\;mmol\;m^{-2}day^{-1}$. The center of subtropical gyre of North Pacific acted as a source of $CO_2(3.09{\pm}0.95\;mmol\;m^{-2}day^{-1})$. Tropical western North Pacific (i.e. the 'warm pool' area and the subtropical western North Pacific) acted as weak sources of $CO_2$($1.07{\pm}1.20\;mmol\;m^{-2}day^{-1}$ and $0.50{\pm}0.53\;mmol\;m^{-2}day^{-1}$, respectively). In the marginal sea, however, the flux was estimated to be $-0.68{\pm}1.17\;mmol\;m^{-2}day^{-1}$, indicating that this area acted as a sink for $CO_2$.

• Ocean and Polar Research
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• v.30 no.4
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• pp.373-378
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• 2008

Long-term tide-gauge data from around the Korean Peninsula were reanalyzed. Both the coastal water and the open sea surrounding the Korean Peninsula appeared to have been influenced by global warming. The long-term change in relative sea levels obtained from tidal stations showed a general rising trend, especially near Jeju Island. It is proposed that global warming may have caused shifting of the path of the Kuroshio branch (Tsushima Warm Current) toward Jeju Island, causing a persistent increase in the water levels along the coast of the island over the last few decades.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.1
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• pp.1-13
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• 2011

The Yellow Sea Cold Water (YSCW) is formed by cold and dry wind in the previous winter, and is known to spread southward along the central trough of the Yellow Sea in summer. Water characteristics of the YSCW and its movement in the northern East China Sea (ECS) are investigated by analyzing CTD (conductivity-Temperature-Depth) data collected from summertime hydrographic surveys between 2003 and 2009. By water mass analysis, we newly define the North Western Cold Water (NWCW) as a cold water mass observed in the study area. It is characterized by temperature below $13.2^{\circ}C$, salinity of 32.6~33.7 psu, and density (${\sigma}_t$) of 24.7~25.5. The NWCW appears to flow southward at about a speed less than 2 cm/s according to the geostrophic calculation. The newly defined NWCW shows an interannual variation in the range of temperature and occupied area, which is in close relation with the sea surface temperature (SST) over the Yellow Sea and the East China Sea in the previous winter season. The winter SST is determined by winter air temperature, which shows a high correlation with the winter-mean Arctic Oscillation (AO) index. The negative winter-mean AO causes the low winter SST over the Yellow Sea and the East China Sea, resulting in the summertime expansion and lower temperature of the NWCW in the study area. This study shows a dynamic relation among the winter-mean AO index, SST, and NWCW, which helps to predict the movement of NWCW in the northern ECS in summer.

• Journal of Korean Society of Disaster and Security
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• v.16 no.4
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• pp.19-31
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• 2023

According to the climate change scenarios, the intensity of typhoons, a major factor in Korea's natural disaster, is expected to increase. The increase in typhoon intensity leads to a rise in wave heights, which is likely to cause large-scale disasters in coastal regions with high populations and building density for dwelling, industry, and tourism. This study, therefore, analyzed observation data of the Donghae ocean data buoy and conducted a numerical model simulation for wave estimations for the typhoon MAYSAK (202009) period, which showed the maximum significant wave height. The boundary conditions for wave simulations were a JMA-MSM wind field and a wind field applying the typhoon central pressure reduction rate in the SSP5-8.5 climate change scenario. As a result of the wave simulations, the wave height in front of the breakwater at Sokcho port was increased by 15.27% from 4.06 m to 4.68 m in the SSP5-8.5 scenario. Furthermore, the return period at the location of 147-2 grid point of deep-sea design wave was calculated to increase at least twice, it is necessary to improve the deep-sea design wave of return period of 50-year, which is prescriptively applied when designing coastal structures.

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.209-220
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• 2010

One of the most difficult tasks in measuring oceanic conditions is to produce oceanic current information. In efforts to overcome the difficulties, various attempts have been carried out to estimate the speed and direction of ocean currents by utilizing sequential satellite images. In this study, we have estimated sea surface current vectors to the south of the Korean Peninsula, based on the maximum cross-correlation method by using sequential ocean color images of SeaWiFS chlorophyll-a. Comparison of surface current vectors estimated by this method with the geostrophic current vectors estimated from satellite altimeter data and in-situ ADCP measurements are good in that current speeds are underestimated by about 15% and current directions are show differences of about $36^{\circ}$ compared with previous results. The technique of estimating current vectors based on maximum cross-correlation applied on sequential images of SeaWiFS is promising for the future application of GOCI data for the ocean studies.

• Journal of the Korean association of regional geographers
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• v.19 no.2
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• pp.340-351
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• 2013

International society has been making a lively discussion about natural disaster by climate change to mitigate natural hazard centering around intra-government association. This study dealt with a strategic mitigation and technical adaptation to support a habitual natural disaster region such as Bangladesh in terms of international cooperation for assistance to protect against the natural hazard. The land-cover on scale of one third of Bangladesh is situated lower than sea level that causes habitual flooding accident which gets increasing in the strengthen every single year. Most of people lives around exterior sea coast being faced with disaster of abnormal storm forming every three year cycle. Especially, the socio-economic status of the people in the coast is usually very low, and it need to get help from international cooperation aid. Therefor, the case study for the vulnerability of natural disaster in Bangladesh on geographical analysis is meaningful to join the international cooperation taking a part of role on technical support and education for adaptation of the natural disaster.

• Journal of the Korean Professional Engineers Association
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• v.38 no.1
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• pp.55-58
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• 2005

Earth quake Tsunamis should be occured between Japan and Korea. There exist long distance fault gone in the sea. So that we can not ignoring tsunami dangerous activity, along the east sea shore line need investment preventing the worst effect roughly 10m Tsunami wave reduce the scale of the disaster.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.668-675
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• 2018

The continuing urbanization and industrialization around the world has required a large amount of power. Therefore, construction of major infrastructure, including nuclear power plants in coastal areas, has accelerated. In addition, the intensity of natural disasters is increasing due to global warming and abnormal climate phenomena. Natural disasters are difficult to predict in terms of occurrence, location, and scale, resulting in human casualties and property damage. For these reasons, the disaster scale and damage estimation in coastal areas have become important issues. The present study examined the predictable weather data and regional ratings and developed estimating functions for wind wave damage based on the disaster statistics in the southern areas. The results of the present study are expected to help disaster management in advance of the wind wave damage. The NRMSE was used for verification. The accuracy of the NRMSE results ranged from 1.61% to 21.73%.