• 한국해양학회지
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• v.18 no.2
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• pp.149-160
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• 1983

Extensive wind, sea level and sea surface temperature (SST) data collected along the east coast of Korea in 1973-1979 were used to ascribe the variations of sea level and SST associated with wind forcing during summer. Alongshore components of wind were dominant but the offshore components were little significance in the southeast coast in summer. The variations in SST and sea level adjusted barometricallyagreed with the upwelling-downwelling processes and showed a rapid response to wind.Appearance of cold water to the surface in the upwelling region concurred well with te periods of positive y-component wind when the tangential line at Ulgi was takem as the y-axis. In general, SST at Ulgi and Gampo as well as the adjusted sea level at Pohang, Ulsan and Busan decreased significantly when strong winds favorable for upwelling persisted for more then three days whereas they increased during the relaxation or unfavorable periods. The period of an upwelling event, on the average, was about 10 days and the mean speed of alongshore sind was 4.0m/sec.

• Journal of the korean society of oceanography
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• v.38 no.3
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• pp.122-134
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• 2003

Low-pass filtered time series of wind, coastal temperature, sea level and current were analyzed to understand the coastal upwelling processes in the southeast coast of Korea. Southerly winds favorable for coastal upwelling were dominant in summer of 1997. Total period of four major wind events amounts to 58 days during one hundred days from June to early September. Coastal temperature is most sensitive to variations of wind. The time lag between the onset of southerly (northerly) winds and decrease (increase) of temperature is 3-18 hours. In the frequency domain the coherent bands have periods of 2.4 and 4.0-5.4 days with respective phase lags of 17 and 27-37 hours. Despite the sensitive response, the magnitude of temperature change is not quantitatively proportional to the intensity or duration of the wind, because it depends on the degree of baroclinic tilting of isotherms built dynamically by the strong Tsushima Warm Current (TWC). Current is particularly strong near the coast and has a large vertical shear during the upwelling periods, which is associated with the baroclinic tilting. Both of current and sea level are poorly coherent with wind or temperature except for the period of 4 days.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.1
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• pp.1-7
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• 2008

To investigate the appearance of cold water by upwelling effect near Ulsan-Gampo of the southeastern coast in Korea on June, 1999, we carried out a numerical experiment by 3-dimensional diagnostic numerical model. Appearance of cold water by the result of numerical experiment was due to upwelling by wind effect at 50-100m depth near Ulsan-Gampo coast. This result was mused by using a model to 2 times of existing wind magnitude near Busan, Ulsan and Gampo that is 5.0m/sec wind. Therefore, to illustrate the phenomenon of extraordinary marine environment like upwelling event and so forth, appropriate wind data at sea should be used instead of those on land.

• Journal of Environmental Science International
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• v.19 no.4
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• pp.399-406
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• 2010

Based on the Results of Annual Monitoring Report of Korean Marine Environment in 2006, it was shown that the coastal area of the East Sea around Korean peninsula could be clearly divided into two parts: the area of upwelling and the North Korean Cold Current. In the upwelling area, the chlorophyll-a and nutrients were increased by the influence of the decrease of temperature and the increase of salinity. These mean that the appearance of cold water due to the upwelling causes nutrient rich water and also resulted in the high productivity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.187-192
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• 2003

To evaluate the oceanographic conditions for the artificial upwelling we measured vertical stratification coefficients, current speed distribution and grain size distribution of bottom sediment in the vicinity of Gukdo and Somaemuldo near Geojedo. There were a strong stratification between surface and bottom layers in summer, the stratification was weak from autumn to winter, and the water was well mixed during winter. In summer nutrient concentration of the bottom layer was 4 times higher than that of the surface layer. Underwater currents were strong in the bottom layer. We conclude that the oceanographic conditions in the area will meet the basic requirement for the construction of artificial upwelling.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.723-734
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• 2003

A three-dimensional numerical model (POM) is implemented to examine coastal upwelling in the northern Japanese coastal region with the passage of Typhoon Oliwa in September 1997. Observed sea surface temperature (SST) decreased suddenly ranging from $-6\;to\;-7^{\circ}C$ in the coastal regions, and such a SST decrease state lasted for more than ten days after the typhoon passed. The model successfully reproduces the observation and gives a clear explanation, the sudden decrease of SST occurred in the process of coastal upwelling with Ekman dynamics. The model also describes the sea surface cooling in the open ocean with vertical velocity.

• Proceedings of KOSOMES biannual meeting
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• 2007.11a
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• pp.9-14
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• 2007

To illusσ'ate the variation of current around artificial upwelling structure which is located in the South sea of Korea, current measurements using ADCP (Acoustic Doppler Current Profiler) during neap and spring tides were carried out on 27th July(summer)， 14th October and 30th November(Autumn), 2006. Current after the set up of artificial upwelling structure were shown different in the upper and lower layer, the boundary between the upper and lower layer was at $27{\sim}30m$ depth in summer. And the boundary layer was formed structure of three layer in Autumn. Upwelling and downwelling flow were occurred around the seamount， and these vertical flows were connected from surface to bottom The distribution of vertical shear and relative vorticity support the vertical flow around the seamount. The strength of vertical shear was higher and the direction of relative vorticity was anticlockwise (+) around the upwelling area.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.347-353
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• 2017

In this study, numerical experiments were conducted to identify distribution of rising flow and flux in the East Sea of Korea, where the coastal upwelling occurs. Temperature and salinity data from CTD observations and NIFS during summer 2013 were applied to the model. Numerical experiments were carried out with different wind speed (3, 6 m/s and 9 m/s) and direction (southerly and southwesterly), which represent the most frequent in summer conditions. As a result of calculation, upwelling flow rate was found to be highest in Pohang between five coasts(Hupo, Youngduk, Pohang, Ulsan and Busan). Comparing with southerly wind conditions, the rising flow rate is about 1.5 times greater when southwesterly wind was applied. Horizontal diffusion of the upwelling area is expected to have a speed of 17~22 km/day when a 9 m/s southwesterly wind is applied. If this wind continues over one week, a cold pool will be generated by upwelling that may reach to the Ulleung 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 the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.323-328
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• 2003

A basic design on a flexible riser in a floating type development system for upwelling deep ocean water is presented. In the numerical study, an implicit finite difference algorithm is employed for three-dimensional riser equations. Fluid and geometric non-linearity and bending stiffness are considered and solved by Newton-Raphson iteration. To keep the depth of end point of a flexible and light riser is very important for upwelling deep ocean water in a floating type development system. Weight attached at the end point of the riser in order to keep its intake depth is designed under the strong surface current and the configuration of the riser is predicted. The results of this study can be contributed to the design of the development system in floating type for upwelling deep ocean water.