• 해양환경안전학회지
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• 제5권1호
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• pp.19-27
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• 1999

This paper is to estimate the long and short term variations of mean sea level in Korean coastal waters by identifying interrelations among the mean sea level, atmospheric pressure and air temperature along the coast. For this, long-term tidal data observed at tidal and weather observation stations were brought into a statistical analysis. It was noted that, in a general sense, an inverse relationship exists between the sea level and the atmospheric pressure and a positive relationship between the sea level and air temperature, respectively. The maximum difference of monthly mean sea level was in the range of 21 to 25 cm at the eastern and southeastern coasts, meanwhile more than 30 cm being in both in southern and western coasts. It was also noted that mean sea level continues to rise in a long-term basis. Long-term variation of mean sea level trends to rise 0.10 ∼ 0.44 cm per year for each region. However, the long-term variation of mean sea level in the isolated islands shows a different trend, Ullngdo being 0.41 cm fall per year and Chejudo being 0.44 cm rise per year.

• 한국해양학회지
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• 제12권2호
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• pp.67-74
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• 1977

With the serial observation data and the tidal records at Busan and Izuhara from 1966 to 1973, the geostrophic current velocity and its relation to the difference of mean sea level of both sides were studied in order to estimate indirectly the average current velocity from the tidal observations. The results shows that the current velocity is estimated by the relationship V=4.016(H-98.3) with the 95% confidence limits of V 4.2 cm/sec. Ther relationship between the observed current velocity and the simultaneous daily mean sea level difference shows a similar result, V=4.717(H-99.6). The two equations were applied to the evaluation of annual variations of current velocity from the average monthly mean sea level data of both stations.

• 한국환경과학회지
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• 제9권1호
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• pp.19-25
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• 2000

As the tideland reclamation is done on a large scale these days, construction work is active in the coastal areas. Facilities in the coastal areas must be built with the tide characteristics taken into consideration. Thus the tide characteristics affect the overall reclamation plan. The analysis of the tide data boils down to a harmonic analysis of the hourly changes of long-term tide data and extraction of unharmonic coefficients from the results. Since considerable amount of tide data of the West Coast are available, the existing data can be collected and can be used to obtain the temporal changes of the tide by being fitted into the tide prediction model. The goal of this thesis lies in assessing whether the mean sea level used in the field agrees with the analysis results from the long-term observation data obtained with their homogeneity guaranteed. To achieve this goal, the research was conducted as follows. First the present conditions of the observation stations, the land level standard, and the sea level standard were analyzed to set up a time series model formula for representing them. To secure the homogeneity of the time series, each component was separated. Lastly the mean sea level used in the field was assessed based on the results obtained form the analysis of the time series.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 추계종합학술대회
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• pp.300-303
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• 2001

The first 7 years of altimeter data from the TOPEX/POSEIDON (T/P) were analyzed to study the surface circulation and its variability in the East Asian Marginal Seas. Long term averaged T/P sea level time series data where compared with in situ sea level measurements from a float-operated type tide gauge around of south Korea and Japan. T/P data are a large contaminated by 60-day tidal aliasing effect, very near the alias periods of M2 and S2. When this 60-day effect is removed, the data agree well with the tide gauge data with 4.6 cm averaged RMS difference. The T/P derived sea level variability reveals clearly the well-known, strong current-topography such as Kuroshio. The T/P mean sea level of North Pacific (NP) was higher than Yellow Sea (YS) and East Sea (ES). The T/P sea level valibility, with strong eddy and meandaring, was the largest in eastern part of Japan and this variability was mainly due to the influence of bottom topography in Kuroshio Extention area.

• 한국해양학회지
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• 제14권2호
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• pp.45-53
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• 1979

The barometric factor is estimated at five stations in the Bay of Biscay from the linear regression between daily mean sea level and atmospheric pressure. The results show that the adjusted sea level change is important in amplitude in spite of the barometric response of the sea level to the atmospheric pressure. The cross-correlations between adjusted sea levels and the two components of wind stress suggest that the adjusted sea level is highly related to the longshore wind stress. The observed phase and the time lag between adjusted sea levels at adjacent stations aree consistent with the hypothesis of the northward travelling continental shelf waves.

• Ocean and Polar Research
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• 제24권2호
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• pp.147-152
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• 2002

Seasonal and interannual variation of volume transport through the La-Perouse Strait were estimated using the difference of sea level observed at Krillion of Sakhalin, Russia, and Wakkanai of Hokkaido, Japan, during the period of 1975-1988. Historical sea level measurements between Russian and Japanese tide gauge data were normalized using an independent direct volume transport measurement. Volume transport from the East Sea (Sea of Japan) to the Sea of Okhotsk varied from -0.01 to 1.18 Sv with an annual mean value of 0.61 Sv. Monthly water transport rates showed a unimodal distribution with its maximum occurring in summer (August) and minimum in winter (December-February). The annual mean volume transport varied from 0.2 to 0.8 Sv during the period of 1975-1988 with the maximum variance of 0.6 Sv.

• 한국해안·해양공학회논문집
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• 제26권3호
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• pp.120-130
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• 2014

서해 연안해역과 제주에서 국립해양조사원이 관측한 기왕의 조위자료를 분석하여 평균해수면을 산출하고, 그 변화추세와 원인을 고찰하였다. 서해안에서 그 동안 진행된 대규모 해안개발사업이 평균해수면을 변화시켰다는 것을 확인할 수 있었으며, 그 영향을 추정하였다. 해안개발로 인한 평균해수면 변화는 지역에 따라 큰 차이를 보였으며, 인천항 1단계 개발로 6.8 cm가 하락한 것을 제외하고는 해안개발로 인해서 평균해수면이 대체로 상승하였으며, 금강하구둑 개발로 인해서 인접한 군산내항에서는 평균해수면이 38 cm가 상승하였다. 또한 해안개발로 인한 해수면 변화량을 보정한 평균해수면 자료를 회귀분석하여 해안개발 이외의 요인 즉 자연적 요인으로 인한 해수면 상승률을 추정하였다. 서해안에서 평균해수면은 지구온난화 등의 자연적인 요인으로 인하여 연평균 1.1~4.4 mm/year가 상승하였으며, 지역적으로 편차가 커서 남부해역에서는 크고, 북부해역에서는 작았다. 제주에서는 해수온도의 상승과 평균해수면 상승과 서로 밀접한 관계가 있어서 수온이 $1^{\circ}C$ 상승하면, 평균해수면은 약 6 mm가 상승하였다. 서해안에서 평균해수면은 대체로 1980년대 중반이전에 비해서 1980년대 중반이후에 급격하게 상승하는 경향을 보였다.

• Journal of the korean society of oceanography
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• 제32권4호
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• pp.171-180
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• 1997

Daily mean sea level variability and its response to atmospheric pressure along the coasts of the northwestern Pacific Ocean are investigated. Daily values of sea level and atmospheric pressure covering the period 1976-1986 from 72 stations are analyzed. The sea level and the air pressure in all the data set have a definite seasonal signal, and higher frequency oscillations at time scales of several days to several weeks are also observed. Among the short-period oscillations of sea level with periods shorter than six months, the period of around 3 or 4 months is dominant in most study stations. According to the statistical analysis of sea level and air pressure, the length scale of sea level variability is smaller than that of air pressure for the present study area. The overall variability of sea level is found to be the smallest around Hokkaido, Japan and the largest in the China coasts. Large short-period (< 6 months) sea level variability is found in the southern coasts of China and Hokkaido, and large long-period (> 6 months) variability in the southern coasts of Japan and Korea along Tsushima Current and Kuroshio. The patterns of air pressure are very similar to those of sea level. The air pressure field is found to account for 31% of the overall sea level variability in the study area. Conside.ins the fact that the results (40%) of Pang and Oh (1995) were obtained through monthly sea level, the present result implies that the short-period sea level variability is less affected by air pressure. Generally the sea level response to air pressure are found to be isostatic, but significantly nonisostatic for the periods around 4 months and for those of 2 to 4 days. In particular, nonisostatic response for higher frequencies seem to be due to the restrictions to water transport necessary for barometric responsein the Korea Strait.

• 한국식품조리과학회지
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• 제14권1호
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• pp.25-32
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• 1998

To measure the contents of several heavy metal elements (Cr, Mn, Ni, Cu, Zn, Cd, Hg, Pb) in Korean seaweeds which are closely related to food resources, various seaweed samples were collected from thirteen to seventeen seaweed-producing districts. The results obtained from the experiment are summarized as follows: 1. The content of heavy metal elements in seaweeds of individual sample ranged from 0.0005 to 25.0373 ppm. Their mean levels were as follows: laver, 0.0024∼3.9297 ppm; sea lettuce, 0.0011∼25.0373 ppm; sea mustard, 0.0005∼23.5071 ppm; sea tangle, 0.0006∼4.8550 ppm. The mean levels of Cd and Pb were specially low in the samples collected from the area II in Kangwon and area Ⅸ in Kyungbook. 2. The mean levels of heavy metal elements of collected samples ranged from 0.0117 to 4.4944 ppm. Laver showed the lowest level of Hg and sea lettuce showed the highest level of Mn. Their mean levels of elements were as follows: laver, 0.0117∼2.3339 ppm; sea lettuce,0.0232∼4.4944 ppm; sea mustard, 0.0129∼1.5139 ppm and sea tangle, 0.0182∼1.7410 ppm. 3. The mean levels of heavy metal elements from several locations ranged from 0.0085 ppm to 8.4148 ppm. The mean levels of heavy metal elements in sea mustard from area V of Kyungbook were the lowest, but the mean levels of heavy metal elements in sea lettuce from area Ⅷ of Kyungnam were the highest. The mean level of heavy metal elements were as follows: laver, 0.3613∼1.1124 ppm; sea lettuce, 0.1415∼8.4148 ppm; sea mustard, 0.0729-3.1182 ppm; sea tangle, 0.0085∼0.7587 ppm. 4. Generally the heavy metal elements were detected in the seaweed samples from all locations. The mean levels of heavy metal elements varied with locations and kinds of samples. The levels of heavy metals of the samples taken from all locations from the East Sea, the South Sea, and the West Sea areas showed 99% safety range.

• 한국해양학회지:바다
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• 제4권2호
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• pp.93-100
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• 1999

금강 하구역의 해수면 변화에 미치는 하구언 수문 작동의 영향을 알아보기 위하여 군산 내항과 외항의 조석자료를 분석하여 비조석 해수면, 평균해수면 및 주요분조의 조화상수를 구하였다. 비조석 및 평균해수면은 하구언 수문 작동이후 내항과 외항에서 낮아졌고 특히 내항에서 급격한 비조석 해수면의 하강을 보였다. 이러한 비조석 해수면의 감소로 내항과 외항사이의 평균해수면 구배가 변화되었으며 이는 주로 하구언으로부터 담수유출량이 감소하여 발생한 것으로 해석되었다. $M_2$와 $S_2$ 분조의 진폭은 내항에서 수분작용 후 급격히 증가하였고, 위상은 다소 감소하였다. $O_1$과 $K_1$ 분조의 위상과 진폭은 변화가 미약하였다 이러한 반일주조 진폭의 큰 변화는 입사파와 하구언에서 반사된 파의 중첩에 의한 것으로 해석된다.