• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.696-700
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• 2004

In the Korean seas, Sea Surface Temperature (SST) and Thermal Fronts (TF) were analyzed temporally and spatially during 8 years from 1993 to 2000 using NOAA/AVHRR MCSST. As the result of harmonic analysis, distributions of the mean SST were $10~25^{\circ}C,$ and generally SST decreased as latitude increased. SST increased in the order as following; the South Sea $(20\~23^{\circ}C),$ the East Sea $(17\~19^{\circ}C)$, and the West $Sea(13\~16^{\circ}C).$ Annual amplitudes and phases were $4\~11^{\circ}C,\;210\~240^{\circ}$ and high values were shown as following; the West Sea $(A1,\;9\~11^{\circ}C),$ the Northern East Sea $(A5,\;8\~9^{\circ}C),$ the Southern East Sea $(A4,\;6\~8^{\circ}C),$ the South Sea $(A3,\;6\~7^{\circ}C),$ the East China Sea $(A2,\;4\~7^{\circ}C)$ and phases; $A3\;(238\~242^{\circ}),\;A4\;(235\~240^{\circ}),\;A5\;(225\~235^{\circ}),\;Al\;(220\~230^{\circ}),\;A2\;(210\~235^{\circ}),$ respectively, Both of them were related inversely except the area A2, therefore the rest areas were affected by seasonal variations. TF were detected by Soble Edge Detection Method using gradient of SST. Consequently, TF were divided into 4 fronts; the Subpolar Front (SPF) based on the Cold Water Mass (low SST and salinity Subartic Water), resulting from the North Korea Cold Current (NKCC) and the East Sea Proper Cold Water in the middle and low layer, and the Warm Water Mass (high SST and salinity Subtropical Water), resulting from the Tsushima Warm Current (TWC) in area A4 and 5, the Kuroshio Front (KF) based on the Kuroshio Current (KC) and shelf waters in the East China Sea (ESC) in A2, and the South Sea Coastal Front (SSCF) based on the South Sea Coastal Water (SSCW) and TWC in A3. Also, the Tidal Front was weakly appeared in AI. TF located in steep slope of submarine topography. Annual amplitudes and phases were bounded in the same place, and these results should be considered to influence of seasonal variations.

• Ocean and Polar Research
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• 제32권3호
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• pp.269-289
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• 2010

In Summer 2008, a multidisciplinary survey was conducted onboard R/V Haeyang 2000 to understand plankton response to the three distinct physico-chemical settings that developed in the Ulleung Basin of the East Sea. Baseline settings of hydrographic conditions included the presence of the thin (<20 m) Tsushima Surface Water (TSW) on top of the Tsushima Middle Water (TMW). It extends from the Korea Strait to $37^{\circ}N$ along the $130^{\circ}E$ and then turns offshore and encompasses the relatively saline (T>$26^{\circ}C$, S>33.7) Ulleung Warm Eddy surface water centered at $36.5^{\circ}N$ and $131^{\circ}E$. A relatively colder and saline water mass appeared off the southeastern coast of Korea. It was accompanied by higher nutrient and chlorophyll-a concentrations, suggesting a coastal upwelling. Most of the offshore surface waters support low phytoplankton biomass (0.3 mg chl-a $m^{-3}$). A much denser phytoplankton biomass (1-2.3 mg $m^{-3}$) accumulated at the subsurface layer between 20-50 m depth. The subsurface chlorophyll-a maximum (SCM) layer was closely related to the nutricline, suggesting an active growth of phytoplankton at depth. The SCM developed at shallow depth (20-30 m) near the coast and deepened offshore (50-60 m). A fucoxanthin/zeaxanthin ratio was high in coastal waters while it was low in offshore waters, which indicated that diatoms dominate coastal waters while cyanobacteria dominate offshore waters. The community structure and biomass of phytoplanktonare closely related to nitrogen availability. Zooplankton biomass was higher in the coastal region than in the offshore region while species richness showed an opposite trend. Zooplankton community structure retained a coastal/offshore contrast. These suggest that summer hydrography is a stable structure, lasting long enough to allow a hydrography-specific plankton community to evolve.

• 한국수산과학회지
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• 제31권6호
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• pp.859-868
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• 1998

제주도 서부 연안역인 한림 정치망어장의 해황특성 (수온 및 염분분포)을 규명하기 위해 1995년과 1996년에 실시한 정선조사의 수온 및 염분자료를 검토$\cdot$분석한 결과를 요약하면 다음과 같다. 1. 제주도 서부연안역중 해안에서 2$\~$3mile 떨어진 외측 (Sta. 1, 2)은 11월부터 익년 5월까지는 제주도 서쪽해역에 출현하는 대마난류수의 주류부가 통과하여 $14^{\circ}C$ 이상의 고수온과 $34.40\%_{\circ}\~34.60\%_{\circ}$의 고염분이 표층부터 저층까지 균질하게 분포하지만 6월부터 10월까지는 제주해역에 저염분수인 중국대륙연안수가 출현하여 표층은 고수은, 저염분수가 되고 중$\cdot$저층은 $11^{\circ}C\~14^{\circ}C$의 저수온, $33.50\%_{\circ}$ 이상의 고염분이 유지되므로 심한 수온 및 염분약층이 나타는데 반해 이 해역은 해쳐 중앙역보다 표층은 수온이 낮고 염분은 높으며 저층은 수온이 높고 염분이 낮은 조석전선역의 수온 및 염분분포가 나타난다. 그러므로 년중 표층수온은 $14^{\circ}C\~23^{\circ}C$ 염분은 $36.60\%_{\circ}\~34.60\%_{\circ}$로 수온의 년교차는 $9^{\circ}C$, 염분의 년교차는 $4.00\%_{\circ}$ 정도로 연안역임에도 불구하고 제주해협 중앙부의 년교차($14^{\circ}C\~20^{\circ}C$, $4.00\%_{\circ}\~10.40\%_{\circ}$)보다 매우 작다. 저층수온은 년중 $14^{\circ}C\~20^{\circ}C$의 범위로 수온 변화폭이 작고 제주해협 서쪽입구에 출현하는 $11^{\circ}C\~13^{\circ}C$의 저온수도 나타나지 않는다. 그러나 저층 염분은 1995년에 $33.60\%_{\circ}\~34.40\%_{\circ}$이지만 1996년의 경우는 6월부터 표$\cdot$저층 모두 현저하게 염분이 저하하여 전층이 $32.00\%_{\circ}$ 이하의 저염분수가 출현하고 있어 이 해역의 동계의 해황은 년별 변화가 적지만 하계에는 중국대륙연안수의 영향, 즉 양자강수의 년별 유출량 변화에 따라 해황의 년별 변화가 심한 해역이 다. 2. 해안에서 2mile 이내의 제주도 서부 연안역은 하계의 경우 조류에 의한 연직혼합으로 표층 저온수, 국지적인 와, 수온, 염분전선 등이 나타나 비교적 복잡한 해황이 출현하며, 특히 비양도 주변 해역의 저층수는 수심변화와 더불어 수온$\cdot$염분이 변해 10m미만의 천소에서 50m의 심소 사이에는 심한 수온$\cdot$염분전선이 형성되고, 월령리와 금릉리 사이에는 고온$\cdot$저염분수인 외측의 표층수가 연안 가까이까지 침입하므로 이 연안에서 비양도를 잇는 선을 중심으로 수온$\cdot$염분전선이 형성된다. 또, 수심 l0m이하의 연안 천소라 할지 라도 저층수는 표층수보다 수온은 $2^{\circ}C\~4^{\circ}C$ 낮고 염분은 $0.02\%_{\circ}\~0.08\%_{\circ}$정도 높다.