• 한국해양학회지:바다
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• 제24권1호
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• pp.79-91
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• 2019

동해 남서부 해역의 해양생태계에 큰 영향을 미치는 연안용승의 변화를 파악하기 위해 1948년 1월부터 2018년 9월까지의 NCEP/NCAR 재분석자료를 이용하여 용승지수를 계산하였다. 평균 용승지수는 4월부터 8월까지 용승이 발생하는 양의 값이 보이며 7월에 최대 값이 나타났다. 용승지수의 장기 변화는 6월과 7월에 통계적으로 유의미한 감소추세가 나타났으며, 5, 6, 7월 용승지수의 합도 통계적으로 유의미한 감소 경향을 보였다. 한반도 주변의 대기압 분석을 통하여 용승지수의 변화 추세는 동해남부해역을 기준으로 북서쪽 영역($35-50^{\circ}N$, $114-129^{\circ}E$)의 기압 변화 추세의 영향이라는 것을 밝혔다. 최근 7년간(2012년-2018년)의 용승지수 분석결과 2017년 7월에 용승지수가 표준편차의 3배 이상 높은 것을 발견하였다. 이것은 중국 북동쪽 지방에 평년과 다르게 저기압이 발달하였고 북태평양고기압이 일본과 대만 사이까지 영향을 주어 동해 남부에 큰 기압 차이가 발생했기 때문이었다. 반면에 평년에 비하여 북쪽의 저기압과 남쪽의 고기압의 영향이 적었던 2018년 7월은 용승지수가 음의 값이었다. 동해남부 연안용승지수는 기후변화에 따라 감소하는 경향을 보이고 경년변동이 커서 생태환경에 대한 영향을 파악하기 위해서는 지속적인 모니터링이 필요하다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2018년도 공동국제학술발표회
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• pp.142-142
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• 2018

• 한국환경과학회지
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• 제19권12호
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• pp.1385-1395
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• 2010

Harmful dinoflagellate Cochlodinium polykrikoides blooms have been frequently occurred in coastal areas of the East Sea since 1995. We compared the oceanic conditions in years 1995, 2001 and 2003 when the C. polykrikoides bloom was strong, and in years 1998 and 2004 when the C. polykrikoides bloom was not appeared. We studied temporal and spatial variation of upwelling and geostrophic currents on the western channel of Korean Strait, an entrance of the East Sea. The period and occurrence area of C. polykrikoides bloom was depended on variation of upwelling in summer. In the distributions of geostrophic current, southward current was dominant near the coast in August, 1998 and 2000. Whereas northward current was dominant near and off the coast in August, 1995 and 2003 which the C. polykrikoides bloom was strong. When compared dominant phytoplankton of the coastal areas in each year, Kuroshio indicator species Proboscia alata and Chaetoceros affine were dominant, respectively, in 2001 and 2003 at every stations. However, the dominant species was variable at each coastal area in 1998 and 2000. In 2003, the abundance of Sagitta elegans which is known as the cold water indicator was low, but the abundance of S. enflata, warm water indicator, was very high in Gangneung compared to Sokcho. It seemed that the distribution of S. elegans is restricted by strong warm water current. In conclusion, it was estimated that the distribution of C. polykrikoides bloom in the coastal area of the East Sea was closely related with the strength of East Korea Warm Current and upwelling.

• 수산해양기술연구
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• 제51권2호
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• pp.212-220
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• 2015

We examined the appearance of cold water in the southwest region of the East Sea, based on the sea surface temperature (SST) at the east coast of Korea and buoy data in Donghae ($37^{\circ}31$'N, $130^{\circ}00$'E, 80 km east away from Donghae port) and Pohang ($36^{\circ}21$'N, $129^{\circ}46$'E, 35 km east away from Ganggu port) from June to August in 2013. Also, the serial oceanographic data of National Fisheries Research and Development Institute (NFRDI) were used to see the oceanographic conditions for June and August in 2013. The SST anomaly at the east coast showed negative values in $3{\sim}6^{\circ}C$ from 2 July. At Janggigab, the SST anomaly showed negative value amount to $10^{\circ}C$ in 8 July. The negative values of SST anomaly continued to the middle of August at Janggigab. The wind speed was 6~11 m/s and the direction was south-southwestly in 1 July. The wind speed amounts to 6~16 m/s in 2 July. It means that the strong wind induced the upwelling effect by a day. The temperature was lower than normal at the depth in 20 m of the East Sea in June and August. The air pressure was 996~998 hPa in the beginning of July. It was the lowest air pressure during the studied period. The correlation was 0.3 between the SST anomaly and air pressure. It was suggested that the appearance of cold water in the East Sea was influenced by a stirring due to wind and low air pressure as well as coastal upwelling.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2008년도 춘계학술발표회
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• pp.147-151
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• 2008

한국 남해안의 인공 용승 해역에서 발생하는 해양 환경 변화를 파악하기 위하여 2002년 및 2007년 하계의 수온, 염분, 영양염 및 유동을 관측하였다. 해중산 설치 전인 2002년의 수온, 염분은 수심 약 $30\sim40m$에서 약층이 형성되었고, 영양염은 표층에서 저층으로 농도가 증가하였다. 해중산 설치 후인 2007년의 수온, 염분은 흐름에 따른 해중산 전면부에서는 수심 약 $10\sim40m$에 약층이 나타났으나, 후면부에서는 수심 약 $20\sim30m$에서 수온 및 염분 약층이 상승하여 나타났다. 영양염은 해중산 상층부 수심 약 $30\sim40m$ 집적되었다. 이와 같이 수온, 염둔 및 영양염의 변화를 일으키는 원인을 파악하기 위하여 수온 및 염분을 이용하여 부력 주파수를 나타내었고 수평유동성분을 이용하여 연직전단 및 상대와도를 계산하였다. 수온, 염분 및 영양염 분포가 변화하는 지역은 수주의 혼합이 잘 이루어지는 해역으로 나타났다. 또한 이러한 해역은 상승류가 해양 환경 변화를 일으키는 주요인으로 밝혀졌다.

• 한국수산과학회지
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• 제43권4호
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• pp.373-379
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• 2010

The artificial upwelling of deep seawater increases primary production. This study conducted a lab-scale experiment to investigate the growth of phytoplankton with the mixing ratio of deep and surface seawater. The chlorophyll content in the sample of pure deep seawater was highest, regardless of the phytoplankton groups. Nutrients contained in the deep seawater positively influenced the growth of phytoplankton. The optimum mixture to apply in an artificial upwelling system was a 1:1 ratio of deep and surface seawater. An experiment considering other environmental conditions, such as luminance and specific gravity, should be performed.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2005년도 추계학술대회지
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• pp.133-137
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• 2005

인공용승구조물 설치해역에서 구조물 설치에 따른 해양환경변화를 조사하였다. 남해안의 전선역에 인접한 연구해역의 남동역에서 고온$\cdot$고염의 분포가 하계에 뚜렷하게 나타났다. 또한 구조물 설치 해역에서는 구조물 설치에 따른 유동의 변화 양상을 볼 수 있었다. 하계 영양염은 표층과 중층에서 구조물 투하 전인 2002년보다 구조물 투하 후인 2005년에 크게 증가하였다. 인공용승구조물설치에 따른 해역의 해양환경특성을 파악하기 위해서는 구조물 효과에 의한 구조물 투하 전$\cdot$후의 보다 장기적인 해양환경조사를 통한 환경변화를 정량적으로 파악할 필요가 있다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.352-355
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• 2006

In this study, the seasonal and inter-annual variation of sea surface current in the Gulf of Thailand were revealed through the use of WOD temperature and salinity data and monthly sea surface dynamic heights (SSDH) from TOPEX/Poseidon and ERS-2 altimetry data during 1995-2001. The mean dynamic height and mean geostrohic current were derived from the climatological data while SSDH data gave monthly dynamic heights and their geopstrophic currents. The mean geostrophic current showed strong southward and westward flow of South China Sea water along the gulf entrance. Counterclockwise eddy in the inner gulf and the western side of the gulf entrance associated with upwelling in the area. Seasonal geostrophic currents show basin-wide counterclockwise circulation during the southwest monsoon season and clockwise circulation during the northeast monsoon season. Upwelling was enhanced during the southwest monsoon season. The circulation patterns varied seasonally and inter-annually probably due to the variation in wind regime. And finally we found that congregation, spawning, and migration routes of short-bodied mackerel conform well with coastal upwelling and surface circulation in the gulf.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.491-494
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• 2006

The west coast of Northern Borneo is strongly influenced by Asian monsoon. Present research using the satellite ocean color (OC) remote sensing has identified some interesting oceanographic phenomena in this area that could be related to the harmful algal blooms (HAB). Occurrence of seasonal upwelling event was noticed off the northern tip of Borneo Island that could be related to the northeast monsoon wind. Harmful algal blooms by Pyrodinium bahamense var. compressum occurred since 1976. Subsequently, during December 2003, there was a report of new HAB by Cochlodinium polykrikoides in Northern Borneo. Analysis of OC images revealed that the Cochlodinium bloom had very high chlorophyll a signal and strong absorption characteristics. Results showed that the Baram River plume and upwelling at Northern Borneo were the source of nutrient for the Cochlodinium bloom in the offshore region. Ocean color images of 2004 showed that the bloom from Northern Borneo had crossed the Balabac Straits, reaching Palawan Island in Philippine. Due to the possibility of transboundary HAB problem, we propose a regional HAB monitoring network for an effective HAB management.

• 한국수산과학회지
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• 제36권5호
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• pp.549-561
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• 2003

Behavior of the Nakdong River plume was studied by the analysis of the observed CTD data and numerical simulations using three-dimensional Princeton Ocean model (POM) in which the river discharge, tides and winds were considered. During the flood season of summer the 30 psu isohaline expands northward to Daebyeon and southwestward to Samcheonpo. The model results show that the isohalines are approximately parallel to the bottom slope, which suggests the possibility of upwelling induced by the topographic effects. Northwesterly wind expands the river plume to the offshore direction so that the inflow of fresh plume water into Jinhae Bay through the Gaduk Channel is constrained, then the coastal upwelling seems to be caused by the wind-driven current at the southern edge of Gaduk Island. Southwesterly wind expands the river plume toward Daebyeon, and the inflow of fresh water into Jinhae Bay is also constrained.