• 한국해양학회지
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• v.19 no.1
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• pp.24-30
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• 1984

A numerical experiment was carried out on thee wind-induced coastal upwelling along the east coast of Korea. Only the variability in coastline geometry is considered and an attempt is made to correlate it with the observation previously performed. In order to approximate the coastline geometry as closely as possible, the finite element method with linear triangular grid is employed. Among several fixed locations of upwelling center found in the model, the one in the southeastern coastal area seems to be just what has been observed most frequently.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.1 s.24
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• pp.1-8
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• 2006

To investigate the variation of marine environments due to set up of artificial structure, we carried out field observations. High temperature and salinity waters near the south frontal area were distributed clearly in the southeastern part of study area during summer season The variation of current structure was also occurred around study area where artificial structure set up. In 2005 after set up of artificial structure, the nutrient concentration increased greater than that in 2002 before set up artificial structures. To illustrate the characteristics of marine environment due to set up of artificial structure, quantitative analyses on the effect of artificial structure are important.

• Proceedings of KOSOMES biannual meeting
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• 2008.05a
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• pp.147-151
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• 2008

In Southern Sea of Korea, there are upwelling area where artificial seamount were built and the environment variations (temperature, salinity, nutrient and current) of before and after built seamount were observed between 2002 and 2007. In 2002, before the seamount was built, there had stratification at 20-30m. And in 2007, seamount was built, stratification of the seamount at the front and back of it were changed by 10-40 m and 20-30 m, respectively. To know the reason of this results, we used temperature and salinity using Brunt-Vaisala Frequency and horizontal current using vertical shear and relative vorticity. They showed upwelling was mainly reason that changed the ocean environment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.4
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• pp.309-314
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• 2013

Temporal and spatial variations and species composition of ichthyoplanktons were investigated by Bongo net in a sea area with the construction of artificial upwelling structure at 13, June, 21 September, and 23 September in 2012. A total of fish eggs was 4,849 ind./$1,000m^3$, and fish larvaes was 641 ind./$1,000m^3$ in the study area. The common fish eggs was Engraulis japonicus which was composed of 57.5%, and unidentified I, II, III and IV were occurred with decreased number of individuals order. For fish larvaes, Pictiblennius yatabei, Repomucenus sp.A, sp.B and Scomber japonicus were dominated, however, other species were Engraulis japonicus, Konosirus puntatus, and unidentified I, II. Temporal variations of fish eggs and larvae were remarkable differed. Higher numbers of fish eggs and larvaes were July 2012, whereas those were lower at August 2012. Spatial variations of those were also significantly differed with higher numbers were at station 2 and 3 during study periods. The total number of fish eggs and larvae was about 4 fold against numbers of those in the compared area far from study area. These results indicated that higher numbers of fish eggs and larvaes were due to influx much more nutrients and food organisms with artificial upwelling.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.3
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• pp.281-287
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• 2022

The distributions of common minke whales observed in the East Sea in ten surveys in May of 2003, 2005, 2006, 2007, 2009, 2010, 2012, 2015, 2016 and 2020 were investigated using satellite sea surface temperature (SST) derived from the Moderate Resolution Imaging Spectrometer (MODIS). Most of the minke whales were observed in the waters off the Korean Peninsula at 36-38.5° N, which is expected as the highly productive coastal upwelling area. Yet, no minke whale was observed in 2006 when a relatively larger scale coastal upwelling occurred with SST at 11℃. In 2016 and 2020, the warm water higher than 17℃ extended widely in the area, and the minke whales were observed in the offshore waters, deeper than 1,000 m. 87.5% of minke whales observed in May appeared in the SST from 13 to 16℃, and they seemed to avoid relatively high temperatures. This suggests that optimum habitat water temperature of minke whales in May is 13-16℃. The SST in the area had risen 1.67℃ from 2003 to 2021, and it was remarkably higher than in other parts of the surrounding areas. The future temperature rising may change the route and timing of the migration of minke whales in the study area.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.4
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• pp.206-211
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• 2011

Low water temperature during the summer associated with the occurrence of cold water zone off Haeundae was studied using the data from CTD observations and a monitoring buoy deployed in Suyeong Bay. Shortterm variability of current was dominant and was not related to the wind. The NE-SW components of wind parallel to the coast contained more than 96% of total variance and could account for major fluctuations of water temperature. Upwelling-response of water temperature was very sensitive so that the temperature began to decrease immediately after the onset of the southwesterly wind. In particular, there were three cases in which SW winds for only two days caused considerable temperature drops. In 2009, four upwelling events shorter than 5 days took place while seven events with periods of 2~18 days were recorded in 2010. During a very intense upwelling for seven days in mid-August 2010, temperature decreased by more than $10^{\circ}C$ in spite of the variable winds. Temperature variability at Gampo, Ulsan, Gijang and Haeundae had similar patterns. CTD observation and satellite imagery showed that the upwelling zone could be extended to the Haeundae-Busan area. According to the wavelet analysis, coherent periods were 2~8 days during the frequent upwelling/downwelling events.

• Proceedings of KOSOMES biannual meeting
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• 2007.11a
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• pp.1-7
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• 2007

To illustrate the variation of oceanic condition around artificial upwelling structure which is located in the South Sea of Korea, cm observations were carried out on December, 2005, April, August and October, 2006. Temperature, salinity and density(sigma-t) was nearly homogeneous through the whole depth by mixing of the seawater in winter. Stratification was not clear in spring, and it was only formed weakly in the surface layer shallower than 10m. Stratification was formed about $10{\sim}20$ m depth in summer and about $30{\sim}40$ m depth in autumn. Vertical gradient of temperature was larger than that in the part of western area along the artificial seamount in summer and autumn. The variation of stratification was also occurred around near the artificial structure area after set up structure.

• 한국해양학회지
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• v.28 no.1
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• pp.52-68
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• 1993

Effects of iron and/or chelator addition on primary production in the equatorial Upwelling system were studied during the TOGA(Tropical oceans and Global Atmosphere) and EPOCS (Equatorial Pacific ocean Climate Studies) cruises in June and November-December of 1989. Changes in the phytoplankton biomass and the degree of iron stress were estimated using the changes in vivo fluorescence before and after the addition of DCMU, which is an inhibitor of photosynthetic electron transposer system. Nitrate uptake was measured using /SUP 45/N labeled KNO$_3$ to estimate the new production. When samples were taken from the Upwelling area where nitrate concentration was higher than 5 uM, there were significant differences between the control and cheated iron treatments in vivo fluorescence and in nitrate uptake capacity. However, CFC (Cellular fluorescence capacity) did not show any significant difference between the control and treatments until nutrient limitation becomes severse and cells become shifted-down. Outside of the Upwelling area where surface nitrate concentration was low (below 0.5 uM), there was no significant difference between the control and treatments in vivo fluorescence and CFC. It is evident that primary and new production in the equatorial Pacific Upwelling region are limited by the availability of iron. However, the physiology of phytoplankton indigenous to this region does not appear to be iron stressed judging from CFC values.

• Proceedings of the KSRS Conference
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• v.1
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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.

• Proceedings of the KSRS Conference
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• v.1
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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.