• 한국해양생명과학회지
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• 제4권1호
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• pp.14-21
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• 2019

본 리뷰는 한국의 중요한 수산자원인 살오징어(Todarodes pacificus)의 동해와 서해 어획량 변동 원인을 살오징어 난/자치어 수송부터 회유경로 및 어장 분포에 관점으로 논의하였다. 우리나라 살오징어 어획량은 1980년 이후 기후체제전환에 따라 변화가 있어 왔으며 이는 동해와 서해의 어획량 변동 경향이 달랐다. PDO (Pacific Decadal Oscillation)는 동해로 유입되는 난류 수송량과 음의 상관관계가 있는데 PDO가 양의 위상이었던 1980s에는 서해에서는 어획량이 많았고 동해에서는 어획량이 적었다. 반면, PDO가 음의 위상이었던 1990s년대에는 동해 어획량이 많고 서해에서는 적었다. 이는 살오징어가 난류를 따라 북상하거나 난류를 거슬러 남하회유를 하는 생활사에 기인된다. 동해의 경우, 난류가 강(약)할 때, 난류경로가 한국의 동해 연안 쪽(동해 중부 해역 및 일본 연안 쪽)으로 치우치게 되는데 이는 PDO가 양의 위상이었던 1980년대에 어장이 울릉도 동편에 위치하였던 반면 PDO가 음의 위상이었던 1990년대에 어장이 동해 연안에 위치한 것과 관련있다. 서해 살오징어 어획량이 증가한 1980년대에는 동해로 유입되는 난류수 수송량이 감소한 반면 서해로 유입되는 난류수는 증가하였으며 이는 서해로 수송되는 유생의 양을 증가시키는 주요 원인이 된다.

• 한국해양학회지:바다
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• 제16권4호
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• pp.155-168
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• 2011

여름철 황해 동부 연안 저층에 형성되는 수온전선을 따라 북쪽으로 흐르는 연안 경계류의 크기와 위치에 영향을 주는 요소들을 3차원 수치모형인 ROMS를 이용하여 살펴보았다. 여름에 수심이 깊은 외해에서는 태양 가열로 강한 성층에 존재하지만 수심이 얕은 연안에서는 조류가 일으키는 저층 혼합으로 해수물성이 연직으로 잘 혼합된다. 이 과정에서 성층화된 외해와 연직 혼합이 잘되고 수온이 높은 연안 사이에서 수온전선이 형성되며, 수온전선을 가로 지르는 방향의 밀도 구배에 의해 수온전선을 따라 북쪽으로 흐르는 연안 경계류가 발생함을 확인하였다. 해류계를 이용한 현장 관측에서도 약 10 cm/s로 북상하는 연안 경계류가 관측되었다. 이러한 수온전선을 따라 북쪽으로 흐르는 연안 경계류는 주로 조류와 바람의 영향을 크게 받는다. 조류에 의한 저층 혼합과 바람에 의한 표층 혼합이 여름철 황해 동부 경계류에 가장 큰 영향을 주는 요소다. 바람에 의한 표층 혼합은 북쪽으로 흐르는 황해 동부 연안 경계류의 폭을 더 넓게 하여 수송량을 증가시킨다. 강물의 유입과 일사량의 변화는 연안 경계류의 세기와 위치 변화에 큰 영향을 주지 않는다. 성층이 강하게 이루어지는 여름철 황해 동부 연안 $36^{\circ}N$에서는 대조기(소조기) 동안 강한(약한) 조류가 북쪽으로 흐르는 해류의 수송량을 증가(감소)시키지만, 동안 경계류의 위치를 크게 변화시키지는 않는다. 연안 경계류의 평균적인 위치는 바람의 세기 변화에 따라 변화하였다.

• Journal of the korean society of oceanography
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• 제33권4호
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• pp.212-218
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• 1998

Three different outflow boundary conditions are considered in modeling the East Sea circulation. The first one is that of the conventional constant volume transport (CT). The second one is the Orlanski radiation boundary condition (OR). The third one is that of the constant sea level just outside the outflow boundary (SL). In the third condition, the outflow current is set to be driven by the sea level differences across the outflow open-boundary lines, based on the recent knowledge that the Tsushima Current is driven by the sea level differences across the inflow and outflow boundaries. In case of OR it takes too much time to reach the steady state, resulting in a large increase of Tsushima Current Water in the basin and low level of kinetic energy. Both CT and SL reach the steady state in a relatively short time. However, SL is more recommendable, because it is based on physical background and generates less numerical noises than CT.

• Ocean and Polar Research
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• 제23권2호
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• pp.133-139
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• 2001

Ocean currents estimated from sea height anomalies derived from inter-calibrated TP/ERS are compared with daily mean currents measured with satellite-tracked drifters. The correlation coefficient between the geostrophic current from TP/ERS and surface current at 15 m depth from drifter tracks was found to be about 0.5. Due to the limitation of satellite ground tracks, small scale eddies less than 80 km are poorly resolved from TP/ERS. One of the interesting results of this study is that coastal currents along the eastern coast of Korea were well reproduced from sea height anomalies when the coastal currents were developed in association with eddies near the South Korean coast. The eddy kinetic energy (EKE) estimated from drifters, TP/ERS, and a numerical model are also compared. The EKE estimated from drifters was about 22 % higher than EKE calculated from TP/ERS. The pattern of low EKE level in the northern basin and high EKE level in the southern East Sea is shown in the EKE estimates derived from both the drifters and TP/ERS.

• 한국항해항만학회지
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• 제36권7호
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• pp.577-583
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• 2012

The transport of radioactive material by sea is strictly governed by the international regulatory regime which is established by both IAEA and IMO. Nonetheless, although the current regime is well established, due to catastrophic results of potential accident, it is essential to keep identifying areas where further enhancement is necessary. This paper reviews the current regulatory regime governing sea transport, such as IAEA Regulations, IMDG Code and INF Code. Then, specific requirements of the INF Code are analyzed for the purpose of identifying areas where improvement is necessary from the perspective of ships. Through this analysis, this paper identifies areas to be improved and proposes to improve the INF Code which can supplement the current regulatory regime for sea transport of radioactive material.

• 한국수산과학회지
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• 제28권5호
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• pp.677-697
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• 1995

우리나라, 일본, 러시아 해역에서 관측된 조위관측 자료에서 얻은 해수면의 장주기변화를 기상과의 관계로 분석해 본 결과, 기상의 효과는 해역에 따라 다르지만 전반적으로 해수면변화의 절반 정도를 설명해주는 것으로 나타났다 해수운동에 의하여 발생하는 해수면변화는 대마해류역에서 가장 크며 대마해류의 영향을 적게 받는 곳일수록 작아져 해수면변화가 대마해류와 관계 있음을 보여준다. 순압해수면 변화가 허용된 수치모델을 사용하여 해수면변화가 해수순환에 미치는 영향을 알아보았다. 그 결과 기본적인 해류형태는 Pang et al. (1993)에 의해 수행된 GCM (Semtner)모델의 결과와 같이 대만 주변 해역에서 지균형조정을 거친 후 등수심선을 따라 대한해협으로 흐르지만, 순압해수면 변화의 허용에 의해 일부 해수가 황해의 중앙을 따라 황해로 유입된 후 서해안을 따라 남하하여 유출되는 황해의 기본순환형태가 나타났다. 이와 함께 쿠로시오해류에 변화를 가할 때 순압해수면 변화에 의해 대륙붕에 장주기파동이 뚜렷해지며 이 파동으로 황해의 기본순환형태가 교란되어 해수가 서해안을 따라 북상하는 순환형태도 나타났다. 황해순환은 겨울철에는 기본순환형태가 북서 계절풍에 의해 강화되고 여름철에는 파동에 의해 교란된 순환구조에 남동계절풍이 합세하는 것으로 보인다. 장주기파동에 의해 나타나는 다른 특징은 대마해류 기원해역의 변화 가능성이다. 지금까지 대마해류의 기원해역은 크게 큐슈섬 남서해역과 대만 주변해역으로 대립되어 왔다. 그러나 이 연구결과는 이들은 서로 위배되는 것이라기 보다는 대마해류 기원의 중요한 두 해역이며 장주기파동에 의해 한쪽이 강화되어 나타나는 것을 보인다. 쿠로시오해류의 변화에 의해 대만 주변해역에 가해진 파동은 강제파로 대한해협으로 전파되며 대한해협에 이르러 일본연안의 파동은 동해로 계속 전파되는 반면, 우리나라 연안의 파동은 해저지형에 의해 반사하게 된다. 반사된 파동은 자유파로 동중국해 대륙붕을 따라 남서방향으로 진행하며 북동방향으로 진행하는 강제파와 더불어 동중국해의 해수면변화를 결정하게 된다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2014년도 춘계학술대회
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• pp.215-220
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• 2014

The report analyze the current situation of shipping industry in Viet Nam, including information about Viet Nam seaborne trade, shipping companies, sea-going fleets, seafarers, major seaports. Afterward it will be disclosed the policy of sea transport in Viet Nam. And finally, the author will give summary and conclusion about shipping industry in Viet Nam.

• 한국환경과학회지
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• 제10권6호
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• pp.423-429
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• 2001

Satellite data, with sea surface temperature(557) by NOAA and sea level(SL) by Topex/poseidon, are used to estimate characteristics on the variations and correlations of 557 and SL in the East Asian Seas from January 1993 through May 1998. We found that there are two climatic characteristics in the East Asian seas the oceanic climate, the eastern sea of Japan, and the continental climate, the eastern sea of China, respectively. In the oceanic climate, the variations of SL have the high values in the main current of Kuroshio and the variations of 557 have not the remarkable seasonal variations because of the continuos compensation of warm current by Kuroshio. In the continental climate, SL has high variations in the estuaries(the Yellow River, the Yangtze River) with the mixing the fresh water and the saline water in the coasts of continent and 557 has highly the seasonal variations due to the climatic effect of continents. In the steric variations of summer, the eastern sea of Japan, the East China Sea and the western sod of Korea is increased the sea level about 10~20cm. But the Bohai bay in China have relatively the high values about 20~30cm due to the continental climate. generally the trends of SST and SL increased during all periods. That is say, the slopes of 557 and SL Is presented 0.29$^{\circ}C$/year and 0.84cm/year, respectively. The annual and semi-annual amplitudes have a remarkable variations in the western sea of Korea and the eastern sea of Japan. In the case of the annual peaks, there appeared mainly In the western sea of Korea and the eastern sea of .Japan because of the remarkable variations of SL associated with Kuroshio. But in the case of the semi-annual peaks, there appeared in the eastern sea of Japan by the influence of current, and in the western sea of Korea by the influence of seasonal temperature, respectively. From our results, it should be believed that 557 and SL gradually Increase in the East Asian seas concerning to the global warming. So that, it should be requested In the international co-operation against In the change of the abnormal climate.

• Fisheries and Aquatic Sciences
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• 제5권3호
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• pp.219-228
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• 2002

Based on the five-year (October 1992 through September 1997) Topex/Poseidon altimeter measurements, we describe the statistical characteristics of the eddy variability in the East Sea in terms of sea surface height anomaly, slope variability, and eddy kinetic energy (EKE). The sea surface height anomalies in the East Sea are produced with standard corrections from Topex/Poseidon measurements. In order to eliminate the high frequency noise in the sea surface height anomaly data, the alongtrack height anomaly data was filtered by about 40 km low-pass Lanczos filter based on Strub et al. (1997) and Kelly et a1. (1998). We find that there exists a distinct spatial contrast of high eddy variability in the south and low eddy energy in the north, bordering the Polar Front. In the northwestern area $(north\;of\;39^{\circ}N\;and\;west\;of\;133^{\circ}E)$ from the Polar Front where the eddies frequently appear, the EKE is also considerabel. The high kinetic energy in the southern East Sea reveals a close connection with the paths of the Tsushima Warm Current, suggesting that the high variability in the south is mainly generated by the baroclinic instability process of the Tsushima Warm Current. This finding is supported by other studies (Fu and Zlontnicki, 1989; Stammer, 1997) wh.ch have shown the strong eddy energy coupled in the major current system. The monthly variation of the EKE in both areas of high and low eddy variability shows a strong seasonality of a high eddy kinetic energy from October to February and a relatively low one from March to September. The sequential pattern of wind stress curl shows resemblance with those of monthly and seasonal EKE and the two sequences have a correlation of 0.82 and 0.67, respectively, providing an evidence that wind stress curl can be the possible forcing for the monthly and seasonal variation of the EKE in the East Sea. The seasonality of the EKE also seems to correlate with the seasonality of the Tsushima Warm Current. There also exists the large spatial and interannual variabilities in the EKE.

• Ocean Science Journal
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• 제40권1호
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• pp.25-44
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• 2005

Long-term, continuous, and real-time ocean monitoring has been undertaken in order to evaluate various oceanographic phenomena and processes in the East/Japan Sea. Recent technical advances combined with our concerted efforts have allowed us to establish a real-time monitoring system and to accumulate considerable knowledge on what has been taking place in water properties, current systems, and circulation in the East Sea. We have obtained information on volume transport across the Korea Strait through cable voltage measurements and continuous temperature and salinity profile data from ARGO floats placed throughout entire East Sea since 1997. These ARGO float data have been utilized to estimate deep current, inertial kinetic energy, and changes in water mass, especially in the northern East Sea. We have also developed the East Sea Real-time Ocean Buoy (ESROB) in coastal regions and made continual improvements till it has evolved into the most up-to-date and effective monitoring system as a result of remarkable technical progress in data communication systems. Atmospheric and oceanic measurements by ESROB have contributed to the recognition of coastal wind variability, current fluctuations, and internal waves near and off the eastern coast of Korea. Long-tenn current meter moorings have been in operation since 1996 between Ulleungdo and Dokdo to monitor the interbasin deep water exchanges between the Japanese and Ulleung Basins. In addition, remotely sensed satellite data could facilitate the investigation of atmospheric and oceanic surface conditions such as sea surface temperature (SST), sea surface height, near-surface winds, oceanic color, surface roughness, and so on. These satellite data revealed surface frontal structures with a fairly good spatial resolution, seasonal cycle of SST, atmospheric wind forcing, geostrophic current anomalies, and biogeochemical processes associated with physical forcing and processes. Since the East Sea has been recognized as a natural laboratory for global oceanic changes and a clue to abrupt climate change, we aim at constructing a 4-D continuous real-time monitoring system, over a decade at least, using the most advanced techniques to understand a variety of oceanic processes in the East Sea.