• Title/Summary/Keyword: Sea surface

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Variations of Sea Level and Sea Surface Temperature in Korean Seas by Topex/Poseidon and NOAA

  • Yoon, Hong-Joo;Kang, Heung-Soon;Lee, Bong-Sic;Jeong, Young-Deok
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.880-883
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    • 2006
  • Altimeter(Topex/Poseidon) and AVHRR(NOAA) data were used to study the variations and correlations of Sea Level(SL) and Sea Surface Temperature (SST) in the North East Asian Seas from November 1993 to May 1998. This region is influenced simultaneously to continental and oceanic climate as the border of the East Sea(Japan Sea). SL and SST have increased gradually every year because the global warming, and presented usually a strong annual variations in Kuroshio extension region with the influence of bottom topography.

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Variations of Sea Level and Sea Surface Temperature in Korean Seas by Topex/Poseidon and NOAA

  • Yoon, Hong-Joo;Kang, Heung-Soon;Cho, Han-Keun
    • Korean Journal of Remote Sensing
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    • v.23 no.1
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    • pp.59-63
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    • 2007
  • Altimeter (Topex/Poseidon) and AVHRR (NOAA) data were used to study the variations and correlations of Sea Level (SL) and Sea Surface Temperature (SST) in the North East Asian Seas from November 1993 to May 1998. This region is influenced simultaneously to continental and oceanic climate as the border of the East Sea (Japan Sea). SL and SST have increased gradually every year because the global warming, and presented usually a strong annual variations in Kuroshio extension region with the influence of bottom topography.

Heat Budget in Incheon Coastal Area in 1994 (1994년 인천 연안역의 열수지)

  • 최용규;윤홍주
    • Journal of Environmental Science International
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    • v.8 no.3
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    • pp.293-297
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    • 1999
  • Based on the monthly weather report of Korea Meteorological Administration (KMA) and daily sea surface temperature (SST) in Incheon harbor of National Fisheries Research and Development Institute, heat budget in Incheon coastal area was estimated. The temperature differences between the sea surface and near bottom were nearly within 1$^{\circ}C$. This indicate the mixing from the sea surface and the bottom. The net heat flux through the sea surface and the advection through the inner and outer bay was affected uniformly to the water body in Incheon coastal area. The net heat flux was about 110W/$m^2$ in maximum value on May, about -80W/$m^2$ in minimum on January. The net heat flux through the sea surface from the solar radiation was about 2.35$\times$${10}^5$W during the year. This heat flux flew out the bay through the advection by the same flux.

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A Study on Anti-Submarine Surveillance Systems using Submarine's Turbulent Wake (비음향신호(난류항적)를 이용한 대잠 탐색 및 감시체계 적용방안 연구)

  • Lee, Yong-Chol;Lim, Se-Han;Park, Jong-Jin;Jin, Jong-Han;Knag, Woong;Lee, Mon-Jin;Kim, Yun-Bae
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.2
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    • pp.138-146
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    • 2012
  • Using Shear-free Ship wake theory it was predicted the detectable submarine's turbulent wake on the sea surface was about 12km long when there was no breaking waves on the sea surface. It means that there are sufficient detectable turbulent kinetic energies on the sea surface as well as in the water. In this paper, we have proposed some concepts of non acoustic anti-submarine surveillance systems; SAR for sea surface surveillance, LIDAR for sub-surface surveillance and propelled gliders for under -water surveillance.

Impact of a New Formula on the Fresnel Reflectance on Microwave Remote Sensing

  • Qing, Xu;Yuguang, Liu
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1340-1342
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    • 2003
  • In microwave remote sensing, the Fresnel reflectance formula is widely used in the sea surface emissivity modeling. As an essential contribution to microwave remote sensing, a new formula on the Fresnel reflectance has been derived based on our understanding of the complex index of refraction and continuity condition of E-M waves at the interface between two mediums. The proposed formula can be used to obtain the emissivity of sea surface, which is useful to retrieve sea surface temperature, sea surface salinity and the brightness temperature. Considering Bragg-resonant scatter, it is useful for the calculation of the normalized radar cross-section, and the retrieval of sea surface wind either.

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Comparative Analysis of Surface Heat Fluxes in the East Asian Marginal Seas and Its Acquired Combination Data

  • Sim, Jung-Eun;Shin, Hong-Ryeol;Hirose, Naoki
    • Journal of the Korean earth science society
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    • v.39 no.1
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    • pp.1-22
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    • 2018
  • Eight different data sets are examined in order to gain insight into the surface heat flux traits of the East Asian marginal seas. In the case of solar radiation of the East Sea (Japan Sea), Coordinated Ocean-ice Reference Experiments ver. 2 (CORE2) and the Objectively Analyzed Air-Sea Fluxes (OAFlux) are similar to the observed data at meteorological stations. A combination is sought by averaging these as well as the Climate Forecast System Reanalysis (CFSR) and the National Centers for Environmental Prediction (NCEP)-1 data to acquire more accurate surface heat flux for the East Asian marginal seas. According to the Combination Data, the annual averages of net heat flux of the East Sea, Yellow Sea, and East China Sea are -61.84, -22.42, and $-97.54Wm^{-2}$, respectively. The Kuroshio area to the south of Japan and the southern East Sea were found to have the largest upward annual mean net heat flux during winter, at -460- -300 and at $-370--300Wm^{-2}$, respectively. The long-term fluctuation (1984-2004) of the net heat flux shows a trend of increasing transport of heat from the ocean into the atmosphere throughout the study area.

Simulation and Evaluation of Sea Surface Observations Using a Microwave Doppler Radar (시뮬레이션을 이용한 마이크로웨이브 도플러 레이더 해면관측법의 평가)

  • Yoshida, Takero;Rheem, Chang-Kyu
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.2
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    • pp.116-122
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    • 2015
  • A simulation is applied to evaluate sea surface observations such as wave heights and surface currents by using a microwave Doppler radar. It is reported that the microwave irradiation width on the sea surface and Fourier transform time taken to sample data for frequency analysis affect Doppler spectra. To investigate the influences by these parameters, Doppler spectra are simulated with various numerical sea surface waves with currents. From the results, in the case of the microwave irradiation width is five times smaller than the wavelength of the sea surface wave, and the Fourier transform time is also five times shorter than the period of the sea surface wave, there is a possibility to measure wave heights accurately with a Doppler radar. In addition, relative surface currents can be estimated by analysis of long Fourier transform time. The simulation results showed the appropriate observing conditions with a microwave Doppler radar.

An Analysis of Changes in Catch Amount of Offshore and Coastal Fisheries by Climate Change in Korea (기후변화에 따른 한국 연근해 어업생산량 변화 분석)

  • Eom, Ki-Hyuk;Kim, Hong-Sik;Han, In-Seong;Kim, Do-Hoon
    • The Journal of Fisheries Business Administration
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    • v.46 no.2
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    • pp.31-41
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    • 2015
  • This study aimed to analyze the relationship between sea surface temperature as a climatic element and catch amount of offshore and coastal fisheries in Korea using annual time series data from 1970 to 2013. It also tried to predict the future changes in catch amount of fisheries by climate change. Time series data on variables were estimated to be non-stationary from unit root tests, but one long-term equilibrium relation between variables was found from a cointegration test. The result of Granger causality test indicated that the sea surface temperature would cause directly changes in catch amount of offshore and coastal fisheries. The result of regression analysis on sea surface temperature and catch amount showed that the sea surface temperature would have negative impacts on the catch amount of offshore and coastal fisheries. Therefore, if the sea surface temperature would increase, all other things including the current level of fishing effort being equal, the catch amount of offshore and coastal fisheries was predicted to decrease.

Measurements of Bistatic Sea Surface Scattering Signals (양상태 해수면 음파산란 측정)

  • 최지웅;나정열;나영남
    • The Journal of the Acoustical Society of Korea
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    • v.20 no.4
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    • pp.81-86
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    • 2001
  • 126-kHz bistatic sea surface scattering measurements were conducted in the shallow waters off the east coasts of Korea. The range from source to receiver was altered to change the scattering angle at the grazing angles of 38% and 52% . Unlike bottom scattering signal, the arrival time and the amplitude of sea surface scattering signals were varied due to the fluctuation of sea surface. The measured forward scattering strengths were compared to model predictions of Kirchhoff approximation and small slope approximation. In overall, the tendency of the scattering strengths showed reasonable agreement among the experimental data, Kirchhoff approximation, and small slope approximation.

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Interannual Variabilities of Sea Surface Temperature and Sea Level Anomaly related to ENSO in the Tropical and North Pacific Ocean System (열대 및 북태평양에서 ENSO와 관련된 표층수온과 해면고도의 경년 변동성)

  • Kim, Eung;Jeon, Dong-Chull
    • Ocean and Polar Research
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    • v.30 no.3
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    • pp.313-324
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    • 2008
  • In order to understand the variation of ENSO-related oceanic environments in the tropical and North Pacific Ocean, spatio-temporal variations of sea surface temperature anomaly (SSTA) and sea surface height anomaly (SSHA) are analyzed from distributions of complex empirical orthogonal functions (CEOF). Correlations among warm pool variation, southern oscillation index, and ocean surface currents were also examined with respect to interannual variability of the warm pool in western tropical Pacific. Spatio-temporal distributions of the first CEOF modes for SSTA and SSHA indicate that their variabilities are associated with ENSO events, which have a variance over 30% in the North Pacific. The primary reasons for their variabilities are different; SST is predominantly influenced by the change of barrier layer thickness, while SSH fluctuates with the same phase as propagation of an ENSO episode in the zonal direction. Horizontal boundary of warm pool area, which normally centered around $149^{\circ}E$ in the tropics, seemed to be expanded to the middle and eastern tropical regions by strong zonal currents through the mature phase of an ENSO episode.