• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• 제4권1호
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• pp.10-21
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• 2001

A new method of laser remote sensing is proposed, based on sensing the sea surface by a narrow laser beam (2-3cm) and analyzing statistically specular reflections. Construction of the angular dependency of the average density of specks versus the aircraft flight horizontal azimuth allows calculation of both intensity and azimuthal properties of the sea surface spectrum. The paper contains the experimental setup and technique, the field measurement data taken onboard an aircraft and the examples of calculated main statistical parameters of sea waves. Their energy-carrying component velocity is found by the mean velocity of an ensemble of specular points at the random sea surface. The surface wave nonlinearity is shown to affect substantially the statistical characteristics measured: mean numbers of specular areas with th given elevation and given slope, arranged along the line of crossing the sea surface by the scanning laser beam. Experimental measurement of a variance in the number of these areas yields a principal possibility to calculate the correlation function of the sea surface without its preliminary modeling.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.165-170
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• 2003

A significant surface net heat loss appears around the Kuroshio and the Tsushima Warm Current regions. The area where the surface heat loss occurs should require heat to be supplied by the current to maintain the long-term annual heat balance. Oceanic heat advection in these regions plays an important role in the heat budget. The spatial distribution of the heat supply by the Tsushima Warm Current near the surface was examined by calculating the horizontal heat supply in the surface layer of the East/Japan Sea, directly from historical sea surface temperature and current data. We have also found a simple estimation of the effective vertical scale of heat supply by the current to compensate net heat loss using the heat supplied by the current in the surface 10m layer. The heat supplied by the current for the annual heat balance was large in the Korea/Tsushima Strait and along the Japanese Coast, and was small in the northwestern part of the East/Japan Sea. The amount of heat supplied by the current was large in the northwestern part and small in the southeastern part of the East/Japan Sea. These features suggest that the heat supplied by the Tsushima Warm Current is restricted to near the surface around the northeastern part and extends to a deeper layer around the southeastern part of the East/Japan Sea.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.518-521
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• 2007

To retrieve Sea Surface Temperature(SST) from NOAA-AVHRR imagery the spilt window atmospheric correction algorithm is generally used. Recently, there have been various new algorithms developed to process these data, namely the variable-coefficient split-window, the R54 transmittance-ratio method, fixed-coefficient nonlinear algorithm, dynamic water vapour (DWV) correction method, Dynamic Water Vapour and Temperature algorithm (DWVT). We used MCSST (Multi-Channel Sea surface temperature) and NLSST(Non linear sea surface temperature) algorithms in this study. The study area is around the Korea sea area (Yellow Sea). We compared and analyzed with various methods by applying each Ocean in-situ data and satellite data. The primary aim of study is to verify and optimize algorithms. Finally, this study proposes an optimized algorithm for SST retrieval.

• Wind and Structures
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• 제36권3호
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• pp.201-213
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• 2023

In this study, the effect of sea surface temperature (SST) on the distribution of vertical wind speed in the atmospheric boundary layer of coastal areas was analyzed. In general, coastal areas are known to be more susceptible to various meteorological factors than inland areas due to interannual changes in sea surface temperature. Therefore, the purpose of this study is to analyze the relationship between sea surface temperature (ERA5) and wind resource data based on the meteorological mast of Høvsøre, the test bed area of the onshore wind farm in the coastal area of Denmark. In addition, the possibility of coastal disasters caused by abnormal vertical wind shear due to changes in sea surface temperature was also analyzed. According to the analysis of the correlation between the wind resource data at met mast and the sea surface temperature by ERA5, the wind speed from the sea and the vertical wind shear are stronger than from the inland, and are vulnerable to seasonal sea surface temperature fluctuations. In particular, the abnormal vertical wind shear, in which only the lower wind speed was strengthened and appeared in the form of a nose, mainly appeared in winter when the atmosphere was near-neutral or stable, and all occurred when the wind blows from the sea. This phenomenon usually occurred when there was a sudden change in sea surface temperature within a short period of time.

• Strategy21
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• 통권41호
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• pp.52-84
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• 2017

After finishing Cold War, the U.S. Navy's ability to Sea control has been gradually eroded last 15-20 years. The global security environment demands that the surface Navy rededicate itself to sea control, as a new group of potential adversaries is working to deny U.S. navy command of the sea. China has been increasing their sea denial capability, such as extended anti-surface cruise missile and anti-surface ballistic missile. To cope with this situation, the U.S. Naval Surface Forces Command has announced Surface Forces Strategy: Return to Sea Control. It is a new operating and organizing concept for the U.S. surface fleet called 'distributed lethality'. Under distributed lethality, offensive weapons such as new ASCMs are to be distributed more widely across all types of Navy surface ships, and new operational concept for Navy surface fleet's capability for attacking enemy ships and make it less possible for an enemy to cripple the U.S. fleet by concentrating its attack on a few very high-value Navy surface ships. By increasing the lethality of the surface ships and distributing them across wide areas, the Navy forces potential adversaries to not only consider the threat from our carrier-based aircraft and submarines, but they now consider the threat form all of those surface ships. This idea of using the distributed lethality template to generate surface action groups and adaptive force package and to start thinking about to increase the lethal efficacy of these ships. The U.S. Navy believes distributed lethality increases the Navy's sea control capability and expands U.S. conventional deterrence. Funding new weapons and renovated operating concept to field a more lethal and distributed force will enable us to establish sea control, even in contested area. The U.S. Navy's Surface Forces Strategy provides some useful implications for The ROK Navy. First the ROK Navy need to reconsider sea control mission. securing sea control and exploiting sea control are in a close connection. However, recently the ROK Navy only focuses on exploiting sea control, for instance land attack mission. the ROK Navy is required to reinvigorate sea control mission, such as anti-surface warfare and anti-air warfare. Second, the ROK Navy must seek the way to improve its warfighting capability. It can be achieved by developing high-edge weapons and designing renewed operating concept and embraced new weapon's extended capabilities.

• 한국전자통신학회논문지
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• 제16권3호
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• pp.525-532
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• 2021

해양에서는 여러 원인들이 복합적으로 작용하여 하나의 원인에 의한 효과를 분리하기 쉽지 않은데, 자기 조직화 지도는 군집 결과에 다른 인자를 추가하여 분석이 가능하다. 따라서 본 연구에서는 해수면 높이 자료로 군집된 결과를 해수면 온도에 적용시켜 분석해보았다. 해수면 높이 자료는 총 6개의 노드로 군집되었다. 해수면 온도와 해수면 높이의 차이에는 1개월 시간 지연이 있어 군집된 결과에 1개월 전 해수면 온도 자료를 적용시켰다. 해수면 온도가 다양하게 분포하였던 140 ~ 150°E의 평균 해수면 온도를 비교해본 결과 노드 1, 3, 5의 경우 해수면 높이 자료에서 뚜렷하게 구분되는 사행하는 모양의 해수면 온도 분포를 찾을 수 있었으나, 노드 2, 4, 6의 경우 해수면 온도 분포는 완만하게 나타났다. 본 연구에서는 해수면 높이 자료로 군집된 결과에 해수면 온도 자료를 적용해보았지만, 추후 바람이나 지형류 자료를 적용시켜 비교해볼 필요가 있다고 판단된다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.621-626
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• 2002

A satellite scatterometer is a microwave radar sensor used to measure the backscattering at a sea surface. This instrument transmits radar pulses to the sea surface and measure the radar energy reflected back towards the source. Changes in wind velocity make sea surface roughness change and then affect on backscattered power. This gives us information of sea surface wind speed. Directions of wind vectors are acquired by multiple, collocated, and nearly simultaneous measurements. It should be noted that the scatterometer observes not the wind directly but the wind stress vector relative to the surface current. This suggests the possibility that the satellite scatterometer winds can include the effect of the surface current. This study shows the evidence that scatterometer measure surface wind stress, not surface winds and presents the velocity structure of oceanic warm and cold eddies.

• 환경영향평가
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• 제20권2호
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• pp.199-205
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• 2011

The Saemangeum embankment construction have changed the flowing on the topography of the coastal marine environment. However, the variety of ecological factors are changing from outside of Saemangeum embankment area. The ecosystem of various marine organisms have led to changes by sea surface temperature. The aim of this study is to monitoring of sea surface temperature(SST) changes were measured by using thermal infrared satellite imagery, MODIS and Landsat. The MODIS data have the high temporal resolution and Landsat satellite data with high spatial resolution was used for time series monitoring. The extracted informations from sea surface temperature changes were compared with the dyke to allow them inside and outside of Saemangeum embankment. The spatial extent of the spread of sea water were analyzed by SST using MODIS and Landsat thermal channel data. The difference of sea surface temperature between inland and offshore waters of Saemangeum embankment have changed by seasonal flow and residence time of sea water in dyke.

• Ocean and Polar Research
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• 제30권3호
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• pp.277-287
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• 2008

We collected information on seasonal and interannual variability of surface chlorophyll a concentration between 1997-2007 from the Northwest Pacific Ocean. Satellite data were used to acquire chlorophyll a and sea surface temperature from six regions: East Sea/Ulleung Basin, East China Sea, Philippin Sea, Warm Pool region, Warm Pool North region, and Warm Pool East region. Mixed layer depth (MLD) was calculated from temperature profiles of ARGO floats data in four of the six regions during 2002-2007. In the East Sea/Ulleung Basin, seasonal variability of chlorophyll a concentration was attributed to seasonal change of MLD, while there was no significant relationship between chlorophyll a concentration and MLD in the Warm Pool region. Interannual anomaly in sea surface temperature were similar among the East Sea, East China Sea, Philippin Sea, and Warm Pool North region. The anomaly pattern was reversed in the Warm Pool East region. However, the anomaly pattern in the Warm Pool region was intermediate of the two patterns. In relation to chlorophyll a, there was a reversed interannual anomaly pattern between Warm Pool North and Warm Pool East, while the anomaly pattern in the Warm Pool region was similar to that of Warm Pool North except for the El $Ni\tilde{n}o$ years (1997/1998, 2002/2003, 2006/2007). However, there was no distinct relationship among other seas. Interestingly, in the Warm Pool and Warm Pool East regions, sea surface temperature showed a pronounced inverse pattern with chlorophyll a. This indicates a strong interrelationship among sea surface temperature-MLD-chlorophyll a in the regions. In the Warm Pool and Warm Pool East, zonal distribution of chlorophyll a concentration within the past 10 years has shown a good relationship with sea surface temperature which reflects ENSO variability.

• 한국측량학회지
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• 제24권2호
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• pp.159-165
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• 2006

본 논문에서는 위성고도계자료를 이용하여 개발된 평균해면모델인 CLS_SHOM과 지구중력장 모델인 EGM96으로부터 평균해면고와 지오이드고를 계산하여 해면지형을 계산하고, 이를 이용하여 지형류의 흐름을 추정하였다 지형류의 추정을 통하여 해양의 물리학적인 특성을 연구할 수 있기 때문에 외국에서는 많은 연구가 수행되어 왔으나 우리나라의 경우에는 연구가 이루어지지 않은 상태이다. 본 연구에서는 지형류에 대한 기초연구로서 동해에서의 지형류 흐름특성을 분석하여 제시하였다. 연구결과 동해지역에 대한 해면지형의 평균은 약 37cm로 계산되었고, 지형류 속도는 평균 -0.028m/sec로 계산되었다. 지형류의 흐름은 태평양 해수가 대한해협을 통과하면서 속도가 증가한 후에 일본열도의 외측단을 따라서 동북동 방향으로 거의 일정한 속도로 흐르다가 좁은 Tsugaru 해협과 Soya 해협을 통하여 유출되며, 한반도의 동해안을 따라서 북쪽으로 흐르다가 Soya해협과 북동북으로 향하여 Okhotsk해로 유출되는 것으로 나타났다.