• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.6
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• pp.453-461
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• 2009

Camera monitoring of topographical changes of intertidal flat was performed at Daehang-ri mud flat outside Semangeum sea dike No. 1, where creation of mud flat was reported after sea dike construction. Ground survey on the mud flat is often limited only to points or few line surveys because of difficulty of walking and limitation of working hours by flood/ebb. This study uses natures of tide that the water lines moving on the intertidal flat during a flood indicate depth contours between low and high tide. Ground coordinates for the water lines extracted from the consecutive images of intertidal flat are calculated and information of topography is acquired by integrating all the water line data. Analysis of 6 camera monitoring data between September 2005 and September 2009 shows 0.127 m deposition per year on the average and variation of deposition/erosion in space and time.

• Proceedings of the Korea Water Resources Association Conference
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• 1996.05a
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• pp.683-688
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• 1996

The purpose of this study is to find seasonal variation of the water circulation in the Chenbuk coastal sea region. Chenbuk coastal sea is investigated with use of a robust diagnostic numerical model. Water circulations in four seasons are calculated diagnostically from the observed water temperature and salinity data and wind data from Kunsan mereorologcal station.

• Journal of Environmental Science International
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• v.15 no.11
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• pp.1017-1025
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• 2006

This study was conducted to evaluate characteristic of water duality in coastal sea of Incheon using a multivariate analysis. The analysis data in coastal sea of Incheon was aquired by the NFRDI data which was surveyed from March 1997 to November 2003. Eleven water quality parameters were determined on each survey The results were summarized as follow : Water quality in Incheon coastal sea could be explained up to 64.62% by three factors which were included in loading of fresh water and nutrients by the land(36.98%), seasonal variation(16.19%), and internal metabolism (11.24%). The results of time series analysis by factor score, in case of factor 1, station 1 influenced by Han river was shown to high factor score and station 3 located by outer sea was shown to low factor score. In case of factor 2, station 1 was appeared to high variation and station 3 was appeared to low variation. The result of cluster analysis by station was classified into three group that has different water quality characteristics. Especially, station 1 which affected by Han river and station 4 which affected by sewage treatment plant was appeared to considerable water quality characteristics against other station. In yearly cluster analysis, three group was classified and water quality in 2003 years due to high precipitation was different to another year. It could be suggested from these results that it is important to control discharge of fresh water by Han rivet and sewage treatment plant for water quality management of coastal sea of Incheon.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.3
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• pp.205-214
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• 2011

Finite element grid refinements with different intensities having 14 K, 52 K and 211 K on the Yellow Sea (YS) have been constructed to make precise tidal simulations. In the meanwhile 57 K grid was made to the extended North Western Pacific (NWP) sea. Numerical simulation were done based on 32 parallel processors by using pADCIRC v 49.21 model. In the YS tidal simulation on YS-G52K and YS-G211K grid structure, KorBathy30s and ETOPO1 bathymetry data are used and 4 major tidal constituents are prescribed from FES2004. Computed results are in good agreement within 0.138 meter in RMS error for amplification and 14.80 degree of phase compared to observed tidal records. Similar error bounds are acquired in the extended NWP tidal simulation on NWP-G57K grid with 8 tidal constituent prescription on the open boundary.

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.109-114
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• 2010

This paper studies the origin of low back-scattering area appeared on the SAR image taken on the coastal waters off the southeast coast of Korea on July 5, 2000. Cold waters were frequently observed during summer on this coastal waters, and quasi-simultaneously taken AVHRR and SeaWiFS images also showed cold surface waters and high concentration of chlorophyll-a, respectively. By synergetic analysis of multi-sensor satellite images, it is strongly suggested that the cold and nutrient rich upwelling waters caused the high phytoplankton density and high biological activities in the water producing natural films for low back-scattering.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.314-325
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• 1994

Characteristics of climate in the eastern coastal regions of Korean Peninsula were studied using the meteorological and coastal sea surface temperature (SST) data which were compiled from 1961 to 1990. In the winter half year (from October to March), air temperature (AT) and precipitation of the eastern coastal regions were considerably higher than those of the western and inland regions, but relative humidity was $8{\sim}15\%$ lower. AT of coastal regions was closely related to the variation of coastal SST. These characteristics were more noticeable in the eastern coastal areas and in lower latitude regions. Quantitatively, the $1.0^{\circ}C$ variation of coastal SST may have resulted in the $1.0^{\circ}C{\sim}1.5^{\circ}C$ variation for AT in coastal regions. In the same way as temperature, vapor pressure in coastal regions was also influenced by coastal SST. Relative humidity change corresponding to the $1.0^{\circ}C$ variation of coastal SST was $3.7\%{\sim}6.5\%$. Net heat exchange amounts were positive (sea surface gaining energy) in all coastal regions. Sea surface gained net heat from March to September, and lost it from October to February. Variation of AT in coastal regions was also related to the sensible and latent heat exchanges. Sensible and latent heat amount corresponding to the $1.0^{\circ}C$ variation of AT were $10Wm^{-2}$ at Kangnung, and $8Wm^{-2}$ at Pohang and $13Wm^{-2}$ at Pusan.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.5
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• pp.228-238
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• 2017

In coastal region, tidal harmonic constants of semi-diurnal tides and nonlinear tides were collected. The observed tide data of KHOA were analyzed by a tide harmonic analysis method. In the southwestern coasts and Han river estuary, nonlinear tides are clearly generated. The generation of tide non-linearity and tide asymmetry is closely related with tide form factor in Korean coastal zone. Tide non-linearity and asymmetry in Mokpo harbour have increased by a series of coastal development projects. The increase has caused rise of high water level and drop of low water level, and increase of tidal range. In Kunsan Outport, tidal range has been declined due to inter-annual change of nonlinear tides after completion of Samangeum sea-dyke.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.1
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• pp.79-88
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• 1991

To study the distribution patterns of epiphytic diatom on Porphyra species and ambient water phytoplankton, samples were collected in the Gaeya Island, Kyukpo, and Mokpo of the Yellow Sea from February 1989 to March 1990. Foully species of epiphytic diatoms were observed. Of these, the dominant species of epiphytic diatoms are Limophora dalmatica, L. abbreviata, Melosira nummuloides, Paralia sulcata, Achnanthes javanica var, subconstricta, Grammatophora oceanica, Navicula sp., Synedra sp., Pinnularia sp., Fragilaria striatula, Cocconeis scutellum var. parva. Licmophora dalmatica predominated troughout the study period. Phytoplankton standing stocks were relatively larger than those of other coastal areas in the Yellow Sea, Korea. Distribution patterns of epiphytic diatoms and the ambient water phytoplankton in Gaeya Island were similar to those of Kyukpo, but different from Mokpo.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.2
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• pp.175-184
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• 2022

This study analyzed the allocation of the skipper's attention during fishing operation in the wheelhouse of a Korean coastal composite fishing vessel by using video observation. To summarize the results, the ratio of lookout, radar and GPS monitoring, which is essential for prevention of collision at sea, was significantly lower than that of other fishing operation due to the attention concentration on the work place during hauling line. In order to reduce exposure to risk of collisions due to concentration of attention to certain tasks such as line hauling, it is necessary to develop an alert system that can notify the approach of other ships or obstruction throughout the ship using information from radar or the automatic identification system. In addition, the order of attention allocation to devices and facilities obtained in this study is expected to be used as basic data for device or facility layout based on the principle of usage frequency in designing wheelhouse for coastal composite fishing vessels in the future.

• Korean Journal of Remote Sensing
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• v.28 no.1
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• pp.95-100
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• 2012

Big swell is often generated offshore and damages the coasts after travelling long distance. In order to prevent coastal damages, wave measurements should be performed offshore as well as coastal waters around Korea. However, in-situ wave measurements are difficult because of high expense of instruments and high risk of operation. Satellite wave measurements using altimeter make it possible to get wave information from the sea difficult to execute field measurements such as the center of the East Sea or exclusive territorial waters. In order to use wave information from the satellite altimeter, it is important to verify altimeter wave data with in-situ data. This paper examines significant wave height data observed by ENVISAT altimeter by comparing wave data observed at Ieodo station.