• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.2
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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.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• v.21 no.1
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• pp.47-54
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• 1993

The major positive sea surface temperature(SST) anomalies not only occur in the region with the most moisture increase, but also in the flank of the area with sinking motion in the Subtropics. As the large amount of water vapor has been increased by the SST anomaly, the increased of the SST is expected to destabilize the air and leads under moist adiabatic unstable conditions, to an enhanced development of moisture cluster. The 4.0 K change of SST causes the positive difference of Brightness Temperature(TB) of about 10.0k for water vapor channels of TOVS over the north eastern and central tropical Pacific Ocean, but the negative difference of TB of about 7.5 K is shifted southward and southeastward to Southern Pacific Ocean along the equator correspondingly. The difference of the TBs for IR water vapor channel $11(7.3{\mu}m)$ and $12(6.7{\mu}m)$ of TOVS indicative of the moisture distribution during two time periods(January 1983 and 1984), leads us to infer significant changes in the entire tropospheric circulations and the dynamic processes over the Pacific Ocean.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.17-17
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• 1995

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.55-62
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• 2006

Correlations between air-temperature variation and SST variation around Jeju Island have been studied with data JRMO($1924{\sim}2004$) and NFRDI($l971{\sim}2000$). Air-temperature has increased about $0.02^{circ}C/year$ for the period of $1924{\sim}2004$ but relatively high 0.035/year for the last 30 years. SST has increased about $0.024^{circ}C/year$ for the period of $1971{\sim}2000$ and relatively high $0.047^{circ}C/year$ in December. According to the analysis of time series of the two kind of variation, the SST and air-temperature are positively correlated. They are generally in phase, and SST anomaly is similar to air-temperature anomaly as well. Consequently, SST variation has high correlation with air-temperature variation around Jeju Island.

• 한국해양학회지
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• v.22 no.4
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• pp.228-235
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• 1987

Based on the hydrographic data for 19 years (1968-1984) at 65 stations in the West Sea of Korea, we investigate the relationships between the sea surface temperature (SST) in winter and the bottom water temperature (BWT) in summer. The spatially-averaged anomalies of BBT are highly correlated with those of SST during the preceding winter. However, due to advection of heat by ocean currents, the spatial pattern of BWT anomaly in summer does not closely resemble that of SST anomaly in the preceding winter.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.3
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• pp.233-241
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• 2020

We examined long-term variations in sea surface temperature (SST) and annual amplitudes of SST around the Korean Peninsula. Two SST data sets with data periods of approximately 51 years and longer than 100 years, respectively, were obtained from the National Institute of Fisheries Science and Japan Meteorological Agency. SST of Korean waters clearly increased during last 51 years (1968-2018), which was 2.5 times higher than the global trend. This significant increasing trend was caused by the dominant increasing SST trend during winter. However, a negative and positive SST anomaly frequently appeared during winter and summer, respectively, in a recent decade. These features of seasonal SST variation have changed the annual amplitude of SST, and resulted in a drastically increasing trend after 2009. Using the longer SST data set, it was revealed that the decreasing SST trend in winter began in the 2000s and the increasing SST trend in summer bagan in the 1990s. During a recent decade, there was a distinctive SST increase in summer, whereas a clear decrease in winter. In summary, the annual amplitude of SST around the Korean Peninsula significantly changed from a decreasing trend to an increasing trend during a recent decade.

• Journal of Environmental Science International
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• v.10 no.2
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• pp.167-171
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• 2001

The magnitudes of sea surface temperature (SST) anomalies at 13 coastal stations along the Korean peninsula in the summer and winter for the past 29years (1969-1997) are more larger than those in the spring and autumn. The periods of positive SST anomalies (negative SST anomalies) longer than 1$^{\circ}C$ were 75(74.5) months in the eastern coast of Korea, 47.8(51.6) months in the southern coast of Korea and 69.5(69.8) months in the western coast of Korea during the past 348 months (1969-1997). The predominant periods of the low-pass filtered monthly SST anomalies are 3 years or 13 months, even another predominant period is 24 months. The spatial variation of SST anomalies were confined by regional seas of the Korean peninsula, such as the East Sea, the South Sea and the West Sea itself.

• Ocean and Polar Research
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• v.30 no.3
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• pp.313-324
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• 2008

In order to understand the variation of ENSO-related oceanic environments in the tropical and North Pacific Ocean, spatio-temporal variations of sea surface temperature anomaly (SSTA) and sea surface height anomaly (SSHA) are analyzed from distributions of complex empirical orthogonal functions (CEOF). Correlations among warm pool variation, southern oscillation index, and ocean surface currents were also examined with respect to interannual variability of the warm pool in western tropical Pacific. Spatio-temporal distributions of the first CEOF modes for SSTA and SSHA indicate that their variabilities are associated with ENSO events, which have a variance over 30% in the North Pacific. The primary reasons for their variabilities are different; SST is predominantly influenced by the change of barrier layer thickness, while SSH fluctuates with the same phase as propagation of an ENSO episode in the zonal direction. Horizontal boundary of warm pool area, which normally centered around $149^{\circ}E$ in the tropics, seemed to be expanded to the middle and eastern tropical regions by strong zonal currents through the mature phase of an ENSO episode.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.403-411
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• 1995

The atmospheric responses to a Sea Surface Temperature Anomaly(SSTA) over the equatorial eastern Pacific Ocean have been investigated using the horizontally fine resolution model based on OSU 2-layer Atmospheric General Circulation Model(AGCM). The SSTAS daring the peak phase of 1982-83 El Nino have been applied to the model as the boundary conditions of the experiment. The model simulates the eastward movement of the rising branch of the Walker circulation. That is, the major features associated with the El Nino such as the increase of the precipitation rate over the center of the Pacific and decrease over the Indonesia, and the 500hPa geopotential height anomaly in the middle latitude are properly describes in the fine resolution model experiment. The model results indicate that this horizontally fine resolution UM can successfully simulate the ENSO anomalies and be more effectivelly used for the study of the climate and the climate changes.

• Journal of Korea Water Resources Association
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• v.38 no.12 s.161
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• pp.985-994
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• 2005

We examined problems of the principal component analysis(PCA), which is able to analyze at the low dimensionality as a methodologv to assess hydrologic time series, and introduced the theory and characteristics of independent component analysis(ICA) that can supplement problems of principal component analysis. We also applied the global sea surface temperature(SST) of the Nino region and assessed the correlation between El $\tilde{n}ino$-Southern Oscillation(ENSO) and SST. The results of examining separation-ability of principal components using mixed signals indicate that the independent component analysis is statistically superior compared to that of the principal component analysis. Finally, we assessed correlation between ENSO and global anomaly SST. The independent component analysis was applied to the $5^{\circ}{\times}5^{\circ}$(latitude and longitude) global anomaly SST in the Nino+3.4 region that is the El $\tilde{n}ino$ observation section. We assessed the correlation with the ENSO years. These results of the analysis show that only one independent component($86\%$) was able to represent the entire behavior and was consistent with the main ENSO years. Finally, we carried out independent component analysis for summer seasonal rainfalls at nine stations and could extract ICs to reflect geographical characteristics. The increasing trend has been shown at IC-1 and IC-2 since 1970s.