• Title/Summary/Keyword: 표층해수

Search Result 394, Processing Time 0.027 seconds

위성 영상과 해양 실측 자료를 활용한 부유사 농도 추정식 유도

  • Lee, Min-Seon;Park, Gyeong-Ae;Jeong, Jong-Ryul;Seo, Gang-Seon;An, Yu-Hwan;Mun, Jeong-Eon
    • 한국지구과학회:학술대회논문집
    • /
    • 2010.04a
    • /
    • pp.136-136
    • /
    • 2010
  • 해색원격탐사에서 해수 type을 광학적 성질에 따라 Case-I water와 Case-II water로 구분한다. Case-I water는 기본적으로 조류 세포 및 그 쇄설물 그리고 미량의 용존 유기물을 포함하며, 맑은 해수인 대양이 이에 속한다. Case-II water는 부유 무기입자, 육상 기원입자 및 높은 용존 유기물 농도, 인간이 만든 유입물을 포함한 탁한 해수이며, 연안 해역의 해수가 이에 속한다(Gordon, 1983). Case-II water에 속하는 연안 해역의 부유사 농도는 해양 연안 환경 변화를 모니터링 할 수 있는 중요한 지표 중 하나이다. 부유사가 연안 환경, 연안 양식장, 어장 환경에 어떤 영향을 주는지 파악할 수 있다. 채수를 통하여 부유사 농도를 추정하는 것은 시간적 경제적 제약이 따른다. 하지만 위성자료와 실측 자료간의 상관관계가 잘 나타나는 계수를 유도하면, 실측없이 위성영상만 있으면 연속적인 부유사 농도 분포를 볼 수 있을 것으로 기대된다. 이런 목적으로 Landsat ETM+ 자료를 이용하여 광양만의 표층 부유사 농도를 추정하였다. 위성 통과시간에 맞춰 2009년 9월 22일과 11월 25일 2차례에 걸쳐 부유사 농도와 반사도를 광양만 16개 정점에서 측정하였다. 부유사 농도는 표층의 해수를 채수하여 GF/F 필터를 이용해 측정되었고, 반사도는 Spectroradiometer를 사용하여 350nm부터 1050nm까지 1nm 간격으로 측정되었다. Landsat ETM+ 자료와 실측 반사도는 원격반사도 $R_{rs}$로 변환되었고, 두 가지 $R_{rs}$를 실측 부유사 농도와 비교하여 부유사 농도 산출 계수를 유도하였다. 경험적으로 구한 계수를 사용하여 위성영상을 부유사 농도로 계산하였으며, 이는 같은 날의 실측 부유사 농도와 비슷한 공간분포를 나타내었다.

  • PDF

Long-Term Fluctuations of Water Temperatures in the Upper 200m off the Southeast Coast of Korea (한국 동해안 외해 표층 200m 수온의 장기변동)

  • KANG Yong-Q;KANG Hye-Eun
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.24 no.6
    • /
    • pp.450-458
    • /
    • 1991
  • The thermal structures and their spatio-temporal fluctuations in the upper 200m layer off the southeast coast of Korea are studied using the bimonthly temperature data for 17years(1967-1983) at 37 stations. We analyzed the fluctuations of the temperatures in the surface(0-100m) and in the subsurface(100-200m) layers. The fluctuations of temperatures in the surface water are dominated by the annual variation, whereas the subsurface layer temperatures contain considerable non-seasonal fluctuations. The distributions of water temperature anomalies in the subsurface layer are closely related with those in the surface layer. The predominant periods of temperature fluctuations in the subsurface layer, other than the annual variation, are 14 and 70 months. The period of 14 months coincides with that of the pole tide or Chandler wobble. The cluster analysis shows that our study area can be divided into the cold, the frontal and the warm regions.

  • PDF

Origin and Spatial Distribution of Organic Matter at Gwangyang Bay in the Fall (추계 광양만의 유기물 기원과 분포 특성)

  • Lee, Young-Sik;Kang, Chang-Keun;Choi, Yong-Kyu;Lee, Sang-Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.12 no.1
    • /
    • pp.1-8
    • /
    • 2007
  • Environment factors related to the distribution of organic matter in surface seawater and sediments were investigated to estimate main pollution sources and range of their influence in Gwangyang Bay. The main pollution sources for the factors that affect organic matter distribution could be divided into three main sources: fresh water runoffs from Seomjin and Dong River, Gwangyang-si domestic sewage, and Yosu Industrial Complex. Considering the characteristics in horizontal distributions of the environmental factors in water column, sediment, and water current regime, the influencing range of these main sources was likely to be divided into three areas within the bay as follows: Area I receiving lots of fresh water from Seomjin River, Area II receiving lots of domestic sewage from Gwangyang-si and fresh water of Dong River, Area III receiving lots of materials from Yosu Industrial Complex. Area I seems to be characterized as low salinity, high concentration of $NO_3-N,\;and\;SiO_2-Si$, Area II as low salinity, high concentration of $NO_3-N,\;NH_4-N,\;and\;SiO_2-Si$, and Area III as high water temperature, high concentration of $NH_4-N,\;and\;PO_4-P$ in water column, high concentration of $NH_4-N,\;PO_4-P,\;and\;SiO_2-Si$ in surface sediments.

Satellite-altimeter-derived East Sea Surface Currents: Estimation, Description and Variability Pattern (인공위성 고도계 자료로 추정한 동해 표층해류와 공간분포 변동성)

  • Choi, Byoung-Ju;Byun, Do-Seong;Lee, Kang-Ho
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.17 no.4
    • /
    • pp.225-242
    • /
    • 2012
  • This is the first attempt to produce simultaneous surface current field from satellite altimeter data for the entire East Sea and to provide surface current information to users with formal description. It is possible to estimate surface geostrophic current field in near real-time because satellite altimeters and coastal tide gauges supply sea level data for the whole East Sea. Strength and location of the major currents and meso-scale eddies can be identified from the estimated surface geostrophic current field. The mean locations of major surface currents were explicated relative to topographic, ocean-surface and undersea features with schematic representation of surface circulation. In order to demonstrate the practical use of this surface current information, exemplary descriptions of annual, seasonal and monthly mean surface geostrophic current distributions were presented. In order to objectively classify surface circulation patterns in the East Sea, empirical orthogonal function (EOF) analysis was performed on the estimated 16-year (1993-2008) surface current data. The first mode was associated with intensification or weakening of the East Korea Warm Current (EKWC) flowing northward along the east coast of Korea and of the anti-cyclonic circulation southwest of Yamato Basin. The second mode was associated with meandering paths of the EKWC in the southern East Sea with wavelength of 300 km. The first and second modes had inter-annual variations. The East Sea surface circulation was classified as inertial boundary current pattern, Tsushima Warm Current pattern, meandering pattern, and Offshore Branch pattern by the time coefficient of the first two EOF modes.

득량만 표층퇴적물내 미량금속원소의 지리적 분포특성

  • 김성수;이재성;김귀영;정래홍;고태승
    • Proceedings of the Korean Society of Fisheries Technology Conference
    • /
    • 2002.10a
    • /
    • pp.152-153
    • /
    • 2002
  • 남해안의 서쪽에 위치한 득량만은 면적이 374$\textrm{km}^2$로 비교적 넓으며, 평균 수심이 약 7.5m(최고수심 40m)로서 남북방향 장축의 길이가 약 50km, 동서방향 폭이 4.6~11.0km이다. 만 남쪽에는 금당도, 거금도, 소록도 등의 섬들 사이의 3개 수로에 의해 해수교환이 이루어지고 있어 남해안의 다른 만에 비해 외해와의 해수교환이 비교적 원활한 편이다. (중략)

  • PDF

Distribution Chara Cteristics of Polychlorinated Biphenyls in the Southern Korea (동해남부 대마난류계에서의 염소화 Biphenyls의 분포특성)

  • LEE Dong-In;Ok Gon;YANG Han-Soeb;CHANG Yoon-Seok
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.30 no.4
    • /
    • pp.679-686
    • /
    • 1997
  • In order to investigate the distribution characteristics of polychlorinated Biphenyls (PCBs) at the southern of Korean East Sea, vertical measurements of temperature, salinity, DO and PCBs were performed by each depth of 5 stations during August - October 1996. Thermocline and salinocline were generally existed at depth of 30 m and water mass current of midwater in the southern of Korean East Sea was distributed below 30 m depth. The distribution of surface water mass in this area was extended to Tsusima area from the southern offshore of the Korean last Sea. In August 1996, concentration range of PCBs had $0.22\~0.36\;ng/\ell$ at surface layer and their concentrations at near Tsusima offshore were relatively decreased. Total mean concentration of PCBs was $0.29\;ng/\ell$ in the sea surface and $0.31\;ng/\ell$ in the middle layer. PCBs seemed to correlate well with suspended particles. And vortical and horizontal distribution of their concentrations showed comparatively uniform pattern. Relatively high compositional ratio of Di- and Tri-PCBs could be found at the sea surface, while compositional ratio of Penta-PCBs dominates over other congener at deep layer.

  • PDF

Estimation of the Surface Currents using Mean Dynamic Topography and Satellite Altimeter Data in the East Sea (평균역학고도장과 인공위성고도계 자료를 이용한 동해 표층해류 추산)

  • Lee, Sang-Hyun;Byun, Do-Seong;Choi, Byoung-Ju;Lee, Eun-Il
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.14 no.4
    • /
    • pp.195-204
    • /
    • 2009
  • In order to estimate sea surface current fields in the East Sea, we examined characteristics of mean dynamic topography (MDT) fields (or mean surface current field, MSC) generated from three different methods. This preliminary investigation evaluates the accuracy of surface currents estimated from satellite-derived sea level anomaly (SLA) data and three MDT fields in the East Sea. AVISO (Archiving, Validation and Interpretation of Satellite Oceanographic data) provides a MDT field derived from satellite observation and numerical models with $0.25^{\circ}$ horizontal resolution. Steric height field relative to 500 dbar from temperature and salinity profiles in the East Sea supplies another MDT field. Trajectory data of surface drifters (ARGOS) in the East Sea for 14 years provide another MSC field. Absolute dynamic topography (ADT) field is calculated by adding SLA to each MDT. Application of geostrophic equation to three different ADT fields yields three surface geostrophic current fields. Comparisons were made between the estimated surface currents from the three different methods and in-situ current measurements from a ship-mounted ADCP (Acoustic Doppler Current Profiler) in the southwestern East Sea in 2005. For offshore areas more than 50 km away from the land, the correlation coefficients (R) between the estimated versus the measured currents range from 0.58 to 0.73, with 17.1 to $21.7\;cm\;s^{-1}$ root mean square deviation (RMSD). For coastal ocean within 50 km from the land, however, R ranges from 0.06 to 0.46 and RMSD ranges from 15.5 to $28.0\;cm\;s^{-1}$. Results from this study reveal that a new approach in producing MDT and SLA is required to improve the accuracy of surface current estimations for the shallow costal zones of the East Sea.

Impact of Seawater Inflow on the Temperature and Salinity in Shihwa Lake, Korea (배수갑문 운용에 따른 시화호의 수온과 염분 변화)

  • Choi, Jung-Hoon;Kim, Kye-Young;Hong, Dae-Byuk
    • Journal of the Korean earth science society
    • /
    • v.21 no.5
    • /
    • pp.541-552
    • /
    • 2000
  • The variations of physical properties due to inflow of seawater by sluice gates operation were observed in Shihwa Lake. The distributions of salinity and temperature were investigated at 11 stations during February, 1997 to July, 1998. The salinity of water mass in Shihwa Lake before gate operation was ranged below 15psu and strong stratification due to inflow of seawater was observed at the depth of 11 m. In July 1997, temperature difference of 10^{\circ}C$ was occurred between the surface and bottom water due to strong solar radiation. During October 1997 to February 1998, inversion of temperature distribution, which the temperature of bottom water was higher than that of surface water, was observed. In July 1997, temperature, salinity, current speed and current direction were investigated by RCM-7 at St.3 for 56 days. When sea water was intruded in Shihwa Lake, the symmetric distribution of temperature and salinity was observed and it seems to be resulted from inflow of seawater with low temperature and high salinity. After January 1998, salinity of Shihwa Lake was increased over 30psu due to continuous gate operation and the stratification was weakened.

  • PDF

Phylogenetic diversity of marine bacteria dependent on the port environment around the Ulleng Island (울릉도 항구의 해양환경에 따른 해양미생물의 분포 변화)

  • Khang, Yongho;Ahn, Minkyung
    • Korean Journal of Microbiology
    • /
    • v.51 no.3
    • /
    • pp.312-317
    • /
    • 2015
  • Pyrosequencing of 16S rDNA tags was used to obtain the bacterial diversity and community structure in the uncultured seawaters as well as in the cultured seawaters, which were collected from the 7 ports (Cheonbu, Hyunpo, Taeha, Namyang, Sadong, Dodong, and Jeodong) and 1 seashore (Guam) around the Ulleng island, Korea. Alphaproteobacteria were the most abundant group in the clean seawaters such as seawaters of Taeha and Sadong ports. Gammaproteobacteria proportion increased depending upon the wastewater amounts mixed with the seawaters such as seawaters of Namyang, Dodong, and Jeodong ports. The genuses of Alteromonas (from samples of Cheonbu, Taeha, Guam, Namyang, Sadong), Shewanella (from sample of Jeodong), and Vibrio (from samples of Hyunpo and Dodong) were dominant group in each of the cultured seawaters incubated in marine broth (Difoco). The results suggest that the incoming wastewaters to the port seawaters contribute to the dynamic change of the marine bacterial community around the Ulleng island.

Analysis of Tide and Tidal Current in Namhae Coastal Waters (남해 주변해역의 조석과 조류분포 해석)

  • Kim, Cha Kyum
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2019.05a
    • /
    • pp.425-428
    • /
    • 2019
  • 본 연구에서는 남해 주변해역의 조석과 조류의 구조특성을 해석하기 위해 현장관측결과와 수치실험결과를 이용하였다. 남해 주변해역의 해수유동은 2003년~2008년 사이 노량수로, 대방수로, 여수수로, 창선수로, 강진만, 앵강만에서 ADCP 및 RCM 9 유속계를 사용하여 각 정점에서 1개월 정도 연속측류를 하였다. 노량수로와 대방수로에서는 ADCP를 사용하여 표층에서 저층까지 3m 간격으로 측류하였고, 여수수로, 창선수로, 강진만과 앵강만에서는 RCM-9 유속계를 사용하여 표층에서 연속 측류하였다. 노량수로 상층에서 동-서 방향의 최대 유속은 약 165~175 cm/sec, 대방수로에서는 창 낙조류 최대유속은 약 200~270 cm/sec, 여수수로에서는 약 85~96 cm/sec 정도 나타났다. 강진만의 표층에서 최대유속의 크기는 창 낙조류 비슷하게 35~46 cm/sec, 앵강만 입구 부근에서 낙 창조류 최대유속은 20~22 cm/sec으로 발생하였다. 또한, 조류수치모형실험을 수행하여 남해 주변해역의 조류분포 특성을 전반적으로 해석하였다.

  • PDF