• 한국해양학회지
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• v.20 no.2
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• pp.1-9
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• 1985

A simple analytic model of the sea surface temperature(SST) is developed in order to understand the effects of the Asian monsoon and the Kuroshio on the annual variations of SST by the Asian monsoon is almost in phase with the incoming radiation whereas that by the Kuroshio is out of phase with the incoming radiation. In the Yellow Sea, due to the heat advection by the Asian monsoon, the yearly mean SST is low and the annual range of SST exceeds 20$^{\circ}C$. The annual range of SST in the northwestern Japan Sea is large because of the combined effects of the Asian monsoon and the cold water advection. In the Kuroshio and in the Tsushima Current regions, the annual range of SST is small and the mean SST is high due to the heat advection by warm currents.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.1
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• pp.25-39
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• 1990

The distributions of the temperature and salinity in Kamak bay which has two channels and three sea bottom topographic parts were studied by taking the detailed hydrographic data at the ebb and flood during four seasons from May, 1988 to Feb., 1989. The general pattern of the distributions of characteristics which the temperature and salinity has in Kamak bay is basically formed by the topography and sea water movement of the bay. The changes of these distributions by seasons mainly come from the heating and cooling of the sea surface and the increase of the run-off. The bay has three remarkable water masses and the their general characteristics are follows: the inner bay water has a stagnation character influenced by the inland and the concave of the sea bottom in the north west, Yosu harbor water has an estuary character of the low salinity caused by the run-off of Somjin river and Yon Tung brooklet in the north east, and the outer bay water has an out-sea character, as it is located near by the big mouth in the south of the bay. The distributions of those water masses at the ebb and flood show some different features due to the flow patterns, and the daily changes of oceanic conditions at the vicinity of Hangdae-ri are so big that it may influence the habitation and production of the living things in the bay.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.232-233
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• 2011

이 연구에서는 최근 25년간(1986-2010년)의 우리나라 기상청 및 일본 기상청 자료를 사용하여 엘니뇨 라니냐 현상과 태풍과의 관계를 분석하였다. 여기서는 엘니뇨감시해역의 해면수온의 기준치와의 차의 5개월 이동평균치가 6개월 이상 계속하여 $+0.5^{\circ}C$ 이상 이 된 경우를 엘니뇨현상, $-0.5^{\circ}C$ 이하가 된 경우를 라니냐현상이라고 정의한다. 그리고 엘니뇨 발생년은 엘니뇨현상이 시작된 해부터 종료된 해까지를, 라니냐 발생년은 라니냐현상이 시작된 해부터 종료된 해까지로 정의한다. 주요 분석 결과는 다음과 같다. 전 기간에 대한 태풍의 연평균 발생 수는 25.4개이다. 이는 60년간(1951-2010년)의 연평균 태풍 발생 수 26.3개보다 약 1개 적은 결과로 최근 지구온난화와 관련하여 태풍의 발생 수가 감소 추세를 보이고 있다는 연구 결과를 뒷받침한다. 엘니뇨 발생년의 연평균 태풍 발생 수는 23.9개이고, 라니냐 발생년의 그것은 24.9개이다. 적도 부근 서부 태평양의 따뜻한 물이 동쪽으로 이동하여 동부 태평양의 해면수온이 평년 이상으로 높아지는 엘니뇨 발생년에 태풍의 발생 수가 감소한다는 사실을 알 수 있다. 태풍의 세기를 나타내는 평균 중심최저기압과 평균 최대풍속은 엘니뇨 발생년에 959.3hPa과 35.8m/s, 라니냐 발생년에 965.5hPa과 33.7m/s 그리고 25년 전 기간에 대하여는 962.3hPa과 35.0m/s이었다. 엘니뇨 발생년의 태풍의 세기가 라니냐 발생년의 태풍의 세기보다 강함을 알 수 있다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.508-520
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• 2016

In this study, variations in water temperature after the passage of typhoons in Korean waters from 2009-2015 were analyzed. Sea surface temperature (SST) images derived from satellite remote sensing data were used, and water temperature information came from real-time mooring buoys at Yangyang, Gangneung, Samcheok and Yeoungdeok, while wind data was supplied by the Korea Meteorological Administration. Differences in SST observed before and after the passage of a typhoon using the SST images were found to be affected by wind direction as well as hot and cool seasonal tendencies. Coastal water temperatures of the eastern part of the Korean peninsula, located to the right of a typhoon, as in the case of typhoons Muifa, Chanhom, Nakri and Tembin, were lowered by a coastal upwelling system from southerly winds across the water's surface at depths of 15m and 25m. In particular, typhoons Chanhom and Tembin decreased water temperatures by about $8-11^{\circ}C$ and $16^{\circ}C$, respectively. However, temperatures to the left of the typhoons were increased by a downwelling of offshore seawater with a high temperature through the mid and lower seawater layers. After the passage of the typhoons, further mixing of seawater at a higher or lower temperature due to southerly or northerly winds, according to the context, lasted for 1-2 or 4 days, respectively.

• 한국해양학회지
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• v.18 no.1
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• pp.43-48
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• 1983

Oceanic temperature inversions, with unstable stratifications, are frequently founed in the surface layer of a few tens meters in the Japan Sea and the Yellow Sea in Winter. Mechanisms responsible for the generation of temperature inversions include the followings: (1) The nat heat loss at the sea suface requires an upward transport of heat from the interior of the ocean y convection, and this convection leads to the temperature inversions. (2) The downward propagation of the annual variation of the sea surface timperature, with an exponential decrease of amplitude and a linear change of phase with depth, generates the surface inversion layer in winter. (3) The cold water cdvection by Ekman drift, of which magnitude decreases exponentially with depth, generates temperature inversions for the three possible mechanisms mentioned above.

• Journal of the Korean earth science society
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• v.39 no.5
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• pp.436-457
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• 2018

In this study, we apply a three-dimensional circulation model, MOHID (MOdelo $HIDrodin{\hat{a}}mico$), and reproduce oceanic variation around the East Asian seas including Korea in 2016. Simulation results are verified by using objective analysis fields (EN4, ARMOR3D, AVISO, and SIO products) and in-situ observation data (serial oceanographic and buoy data). Verification results show that general characteristics of the water temperature, sea level anomaly, surface velocity, and mixed layer depths simulated by MOHID are similar with those of the objective analysis fields in the East Asian seas. Especially, when buoy data in the coastal areas are compared, correlation coefficients of sea surface temperature and sea level anomaly are both over 0.8 and normalized standard deviations are between 0.85 and 1.15, respectively. However, it is analyzed that additional improvement would be necessary in the representation of thermocline structure in the East Sea and strong stratification phenomena in the Yellow and South Sea in summer.

• 한국해양학회지
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• v.27 no.1
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• pp.35-45
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• 1992

This paper is concerned with the development and application of a stochastic model for predicting E1 nino phenomenon. For this, first a general criterion for determining E1 nino phenomenon, including period and strength, which is based on partial sum of monthly sea surface temperatures (SST) anomalies, is proposed, Secondly, the annual fluctuations, periodicity and dependence of monthly mean of equatorial Pacific SST during the period 1951-1990 are analyzed. Based on these, time series nonlinear regression model for the prediction of SST have been derived. A statistical procedure for using the model to predict the SST have been derived. A statistical procedure for using the model to predict the SST level is also proposed.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.322-323
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• 2000

점농어, Lateolabrax maculatus는 옛부터 우리나라의 횟감으로 이용되던 어종으로 대 크기가 100cm를 넘는 대형종이다. 그리고, 성장이 빠르고 담수적응력이 강할 뿐만 아니라 수온변화에도 강해 해상가두리 및 축제식 양식대상어종으로 선호하고 있는 실정이다. 이러한 점농어의 양식활성화를 위해서는 전용 배합사료의 개발이 시급하다. 그러나 배합사료개발에 관한 연구는 거의 없어 효율적인 해면양식이 이루어지고 있지 않다. 본 연구에서는 점농어의 생산량 증대를 위한 일련의 연구로 점농어 배합사료 개발에 필요한 기초자료를 제공하기 위하여 단백질 수준을 달리한 사료를 제작, 공급하여 점농어의 사료내 단백질 요구량 수준을 알아보고자 실시하였다. (중략)

• Journal of Fisheries and Marine Sciences Education
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• v.10 no.1
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• pp.15-30
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• 1998

The variation of the catches of Skipjack(Euthynnus pelamis) and the relationships between the SST and the fishing ground is examined using the catches data of skipjack obtained by Iwawada Fisheries Cooperative of Chiba Prefecture in Japan from 1982 to 1988. The annual mean catch for Skipjack was 151,375.1kg. the annual fluctuation of catch was that the catch in 1984 was increasing, but it was decreased less than 50% in 1985, and was repeated after being a little recovered in 1986, and it was recovered with the level of 1984 in 1988. The fluctuation of catch for Skipjack in every fishing term is that daily mean catch of the primary fishing term (January, February and March) is 894.6kg, but the middle fishing term(April and May) more than four times of the primary fishing term is 3,666.0kg, the last fishing term(June and July) was decreasing at 767.9kg and the fishing ground gradually becomes extinct. The annual mean SST in fishing ground was an extent of from $19.0^{\circ}C$ to $20.2^{\circ}C$, the mean SST of every year except 1983 was from $19.0^{\circ}C$ to $19.9^{\circ}C$. It is said that the optimum SST of Skipjack in Sotobo sea area is the degree of $19.0^{\circ}C$. Therfore, the thing which will guess the time and the location appeared the optimum SST is the very important factor to operate efficiently. About the extent of SST in fishing ground, it was from $17.0^{\circ}C$ to $19.0^{\circ}C$ on March, from $17.5^{\circ}C$ to $20.5^{\circ}C$ on April and from $17.5^{\circ}C$ to $23.5^{\circ}C$ on May, which the extent of SST was gradually larger and larger, on June from $21.0^{\circ}C$ to $23.5^{\circ}C$, fishing ground was formed only the degree of SST more than $21.0^{\circ}C$.

• 한국해양학회지
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• v.24 no.3
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• pp.121-131
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• 1989

Cold water observed at sea surface near the southeastern coast of Korea in summers 1982 and 1983 was studied by using data of hydrography, sea level, wind and satellite image. In summer season when water column shows 3-layered structure a "full" upwelling occurs by southwesterly transient wind continuing for several days. During upwelling event, surface water of high temperature moved offshore, middle water of low temperature outcropped to the sea surface, and sea level was lowered, however, equilibrium depth of surface layer was not changed. It may be concluded that cold water at the surface originates from middle layer and strong surface front is a result of surfacing of seasonal thermocline. In order to see the relationship between position of surface front and wind input, a model of Csanady (1982) was applied in a rigid lid approximation. The results show that frontal position can be determined by wind input and water structure near the southeastern coast of Korea. Cold water in summer can appear at the sea surface only when there is wind larger than a minimum wind impulse of order $10m^2/sec$.