• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 추계학술발표회
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• pp.219-225
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• 2003

The present study intends to assess the long-term steric sea-level change and its prediction, and potential impacts to the sea-level rise due to the 21st global warming in the coastal zone of the Korea in which much socioeconomic activities have been occurred. The analysis of the 23 tide-gauge data near Korea reveals the overall mean sea-level trend of 2.31 mm/yr.In the satellite altimeter data (Topex/Poseidon and ERS), the sea-level trend in the East Sea is 4.6mm/yr. Both are larger than those of the global average value. However, it is quite questionable that the sea-level trends with the tide-gauge data on the neighboring seas of Korea relate to global warming because of the relatively short observation period and large spatial variability. It is also not clear whether the high trend of altimeter data in the East Sea is related to the acceleration of sea level rise in the Sea, short response time of the Sea, natural variability such as decadal variability, short duration of the altimeter. The coastal zone of Korea appears to be quite vulnerable to the 21st sea level rise such that for the I-m sea level rise with high tide and storm surge, the inundation area is 2,643 km2, which is about $1.2\%$ of total area and the population in the risk areas of inundation is 1.255 million, about $2.6\%$ of total population. The coastal zone west of Korea is appeared to be the most vulnerable area compared to the east and south. In the west of the Korea, the North Korea appears to be more vulnerable than South Korea. In order to cope with the future possible impact of sea-level rise to the coastal zone of Korea effectively, it is essential to improve scientific information in the sea-level rise trend, regional prediction, and vulnerability assessment near Korean coast.

• 수산해양기술연구
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• 제54권2호
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• pp.146-156
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• 2018

Acoustic surveys were conducted in the seas surround the South Korea (South Sea A, South Sea B (waters around the Jeju Island), West Sea and East Sea) in spring and autumn in 2016. First, the vertical and horizontal distributions of fisheries resources animals were examined. In most cases vertical acoustic biomass was high in surface water and mid-water layers other than South Sea A in autumn and West Sea. The highest vertical acoustic biomass showed at the depth of 70-80 m in the South Sea A in spring ($274.4m^2/nmi^2$) and the lowest one was 10-20 m in the West Sea in autumn ($0.4m^2/nmi^2$). With regard to the horizontal distributions of fisheries resources animals, in the South Sea A, the acoustic biomass was high in eastern and central part of the South Sea and the northeast of Jeju Island ($505.4-4099.1m^2/nmi^2$) in spring while it was high in eastern South Sea and the coastal water of Yeosu in autumn ($1046.9-2958.3m^2/nmi^2$). In the South Sea B, the acoustic biomass was occurred high in the southern and western seas of Jeju Island in spring ($201.0-1444.9m^2/nmi^2$) and in the southern of Jeju Island in autumn ($203.7-1440.9m^2/nmi^2$). On the other hand, the West Sea showed very low acoustic biomass in spring (average NASC of $1.1m^2/nmi^2$), yet high acoustic biomass in the vicinity of 37 N in autumn ($562.6-3764.2m^2/nmi^2$). The East Sea had high acoustic biomass in the coastal seas of Busan, Ulsan and Pohang in spring ($258.7{\sim}976.4m^2/nmi^2$) and of Goseong, Gangneung, Donghae, Pohang and Busan in autumn ($267.3-1196.3m^2/nmi^2$). During survey periods, fish schools were observed only in the South Sea A and the East Sea in spring and the West Sea in autumn. Fish schools in the South Sea A in spring were small size ($333.2{\pm}763.2m^2$) but had a strong $S_V$ ($-49.5{\pm}5.3dB$). In the East Sea, fish schools in spring had low $S_V$ ($-60.5{\pm}14.5dB$) yet had large sizes ($537.9{\pm}1111.5m^2$) and were distributed in the deep water depth ($83.5{\pm}33.5m$). Fish schools in the West Sea in autumn had strong $S_V$ ($-49.6{\pm}7.4dB$) and large sizes ($507.1{\pm}941.8m^2$). It was the first time for three seas surrounded South Korea to be conducted by acoustic surveys to understand the distribution and aggregation characteristics of fisheries resources animals. The results of this study would be beneficially used for planning a future survey combined acoustic method and mid-water trawling, particularly deciding a survey location, a time period, and a targeting water depth.

• 대한원격탐사학회지
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• 제39권6_2호
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• pp.1651-1669
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• 2023

해빙(sea ice)은 현재 전 세계 해양 면적의 약 7%를 차지하고 있으며 계절적, 연간 변화를 보이고 주로 극지방과 고위도 지역에 나타난다. 해빙은 대규모 공간 규모에서 다양한 종류로 형성되며 석유 및 가스탐사, 기타 해양활동이 급속히 증가하는 발해해는 해양 구조물 피해 및 해상 운송, 해양 생태계에 심각한 영향을 미치기 때문에 시계열 모니터링을 통해 해빙의 면적 및 유형 분류를 분석하는 것이 매우 중요하다. 현재 고해상도 위성영상 및 현장 실측 자료를 바탕으로 해빙의 종류 및 영역에 대한 연구가 진행되고 있지만 현장 실측자료를 획득하여 해빙 모니터링에는 한계가 있다. 고해상도 광학 위성영상은 광범위에서 해빙의 유형을 육안으로 탐지하고 식별할 수 있고, 짧은 시간해상도를 갖는 해양위성인 천리안 2B호(Geostationary Ocean Color Imager-II, GOCI-II)를 이용하여 해빙 모니터링의 공백을 보완할 수 있다. 이 연구에서는 고해상도 광학위성영상을 이용하여 생산된 학습자료를 기반으로 규칙기반 기계학습 모델을 훈련시키고 이를 GOCI-II 영상에서 탐지를 수행함으로써, 해빙 모니터링 활용 가능성을 알아보고자 하였다. 학습 자료는 발해(Bohai Sea)의 2021-2022년 랴오둥만(Liaodong Bay)을 대상으로 추출하였으며, GOCI-II를 활용한 Random Forest (RF) 모델을 구축하여 기존 normalized difference snow index (NDSI) 지수 기반 및 고해상도 위성영상에서 획득된 해빙 영역과 정성적 및 정량적 비교 분석하였다. 본 연구 결과 해빙의 영역을 과소평가한 NDSI 지수 기반 결과와 달리 비교적 자세한 해빙 영역을 탐지하였으며 유형별 해빙을 분류할 수 있어 해빙 모니터링이 가능함을 확인하였다. 향후 지속적인 학습 자료 및 해빙형성에 영향인자 구축을 통해 탐지 모델의 정확도를 향상시킨다면 고위도 해양 지역에서 해빙 모니터링 분야에 활용할 수 있을 것으로 기대된다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 추계학술발표회
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• pp.191-193
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• 2003

본 연구에서는 인공위성 해색센서 SeaWiFS (Sea-Viewing Wide Field-of-View Sensor)에서 관측한 영상을 이용하여 한반도 주변 식물플랑크톤 색소농도의 시공간적 분포 특성에 대하여 살펴보았다. 동해에서 식물플랑크톤 색소농도는 봄철과 가을철에 공간적으로 높은 농도를 나타내었다. 색소농도는 봄철인 4월에 동해 극전선 남부해역에서 가장 높고, 5월에는 극전선 북쪽해역에서 높은 농도가 나타났다. 하계는 거의 저농도를 나타내고 동계가 하계보다 공간적으로 높은 농도를 나타내었다. 그리고 한국 동해안을 따른 warm streamer주변과 서해와 남해연안의 연안선을 따라서 연중 높은 농도가 존재하였다 특히, 여름철 8월부터 12월까지 중국 양쯔강 주린 높은 색소농도가 남해연안 주변까지 연결된 형태로 나타난 것이 특징적이었다.

• Journal of the korean society of oceanography
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• 제31권3호
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• pp.123-133
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• 1996

We describe here the shallow water tides in the seas around Korea, obtained from a nonlinear barotropic model of tides in a domain encompassing the Yellow Sea, the East China Sea and the East Sea (Sea of Japan). As expected, the shallow water tides are large in the shallow marginal areas around the Yellow Sea, with the M4 tide reaching amplitudes as high as 10 cm near the Korean coast, and quite small in the East Sea. However, we also find that the regions east of the Yangtze River ($126^{\circ}E,$ $30^{\circ}N$) in the East China Sea also sustain large shallow water tides, with $M_{4}$, amplitudes reaching 5 cm. Such large shallow water tides are an important component of altimeter-measured sea levels and should not be ignored in any altimetric analyses of the Yellow Sea and the East China Sea. This study also highlights the desirability of very high resolution models to derive accurate shallow water tides in coastal regions.

• Journal of Astronomy and Space Sciences
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• 제35권2호
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• pp.105-109
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• 2018

El $Ni{\tilde{n}}o$ is the largest fluctuation in the climate system, and it can lead to effects influencing humans all over the world. An El $Ni{\tilde{n}}o$ occurs when sea surface temperatures in the central and eastern tropical Pacific Ocean become substantially higher than average. We investigated the change in sea surface temperature in the Pacific Ocean during the El $Ni{\tilde{n}}o$ period of 2015 and 2016 using the advanced very-high-resolution radiometer (AVHRR) of NOAA Satellites. We calculated anomalies of the Pacific equatorial sea surface temperature for the normal period of 1981-2010 to identify the variation of the 2015 El $Ni{\tilde{n}}o$ and warm water area. Generally, the warm water in the western tropical Pacific Ocean shifts eastward along the equator toward the coast of South America during an El $Ni{\tilde{n}}o$ period. However, we identified an additional warm water region in the $Ni{\tilde{n}}o$ 1+2 and Peru coastal area. This indicates that there are other factors that increase the sea surface temperature. In the future, we will study the heat coming from the bottom of the sea to understand the origin of the heat transport of the Pacific Ocean.

• 동아시아식생활학회지
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• 제11권3호
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• pp.209-218
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• 2001

This study was conducted to examine the water absorption, water-holding capacity, color and mineral contents in natural and cultured dried sea mustards on soaking treatment. Four dried samples of natural and cultured sea mustards were used for the experiments. The effects of soaking treatment on water absorption and water-holding capacity in sea mustards were examined, as the results, these were rapidly accelerated 5 minutes after soaking. It showed that water-holding capacity was significantly high in the case of high absorption of water by soaking. The L, a and b values were increased until 30 minutes after soaking. There was significant difference for potassium content between dried natural and dried cultured sea mustards and the natural sea mustard was 10 times as high as the cultured sample. All mineral elements in these materials were significantly decreased and especially, potassium were significantly more decreased at 50~80% of total content by soaking treatment. Ca/ P ratio in these materials by soaking was about 2~3 : 1 levels.

• 한국식품영양학회지
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• 제8권4호
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• pp.293-300
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• 1995

This study was carried put to investigate the preference and consumption of Korean traditional foods. Questionnaires were completed by 210 academic female high school students and also by 210 vocational female high school students. The family income of academic high school students was significantly higher than that of vocational high school students and the family size of academic high school students was lancer than that of vocational high school students In the food consumption, academic high school students are broiled foods more frequently and vocational high school student ate noodles more frequently. Academic high school student showed a higher average in the preference of salted sea foods than that of vocational high school students. In the intake of salted sea foods, academic high school student had a higher intake frequency. The preference and intake frequency of salted sea foods increased significantly with their family's income. Also academic high school student showed a higher average in Korean traditional food knowledge. And this knowledge increased significantly with their family's income.

• 한국환경과학회지
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• 제13권11호
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• pp.965-985
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• 2004

The investigation of driving mechanism for the formation of tropical night in the coastal region, defined as persistent high air temperature over than 25$^{\circ}C$ at night was carried out from August 14 through 15, 1995. Convective boundary layer (CBL) of a 1 km depth with big turbulent vertical diffusion coefficients is developed over the ground surface of the inland basin in the west of the mountain and near the top of the mountain, while a depth of thermal internal boundary layer (TIBL) like CBL shrunken by relatively cool sea breeze starting at 100 km off the eastern sea is less than 150 m from the coast along the eastern slope of the mountain. The TIBL extends up to the height of 1500 m parallel to upslope wind combined with valley wind and easterly sea breeze from the sea. As sensible heat flux convergences between the surface and lower atmosphere both at the top of mountain and the inland coast are much greater than on the coastal sea, sensible heat flux should be accumulated inside both the TIBL and the CBL near the mountain top and then, accumulated sensible heat flux under the influence of sea breeze circulation combined with easterly sea breeze from sea to inland and uplifted valley wind from inland to the mountain top returning down toward the eastern coastal sea surface should be transported into the coast, resulting in high air temperatures near the coastal inland. Under nighttime cooling of ground surface after sunset, mountain wind causes the daytime existed westerly wind to be an intensified westerly downslope wind and land breeze further induces it to be strong offshore wind. No sensible heat flux divergence or very small flux divergence occurs in the coast, but the flux divergences are much greater on the top of the mountain and along its eastern slope than on the coastal inland and sea surfaces. Thus, less cooling down of the coastal surface than the mountain surface and sensible heat transfer from warm pool over the coast into the coastal surface produce nocturnal high air temperature on the coastal inland surfaces, which is not much changed from daytime ones, resulting in the persistence of tropical night (nocturnal thermal high) until the early in the morning.

• 한국수산과학회지
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• 제32권3호
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• pp.368-373
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• 1999

Topex/Poseidon sea surface heights are compared to tide gauge sea levels in the South Indian Ocean in the period of January 1993 to December 1995. A user's handbook (AVISO) for processing sea surface height data was used in this study. Topex/Poseidon sea surface heights were obtained from satellite data at the proximity of tide gauge stations. These data were reproduced by a linear interpolation with the interval of 10 days and were processed by the Gaussian filter with a 60-day window. The tide gauge sea levels were obtained in the same manner as the satellite data. The main results on RMS (Root-Mean-Square) and CORR (CORRelation coefficient) in our study were shown as follows: 1) on the characteristics between two data (in-situ and model data), the results (RMS=2.96 cm & CORR=$92\%$ in the Amsterdam plateau, and RMS=3.45 cm & CORR=$59\%$ in the Crozet plateau) of the comparison of Topex/Poseidon sea surface heights with tide gauge sea levels, which was calculated by in-situ data of obsewed station showed generally low values in RMS and high values in CORR against to the results (RMS=4.69 cm & CORR=$79\%$ in the Amsterdam plateau, and RMS= 6.29 cm & CORR= $49\%$ in the Crozet plateau) of the comparison of Topex/Poseidon sea surface heights with tide gauge sea levels, which was calculated by model data of ECMWF (European Center for Medium-range Weather Forecasting), and 2) on the characteristics between two areas (Kerguelen plateau and island), the results (RMS=3.28 cm & CORR= $54\%$ in the Kerguelen plateau) of open sea area showed low values in RMS and high values in CORR against to the results (RMS= 5.71 cm & CORR=$38\%$ in the Kerguelen island) of coast area, respectively.