• Korean Journal of Remote Sensing
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• v.12 no.2
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• pp.126-138
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• 1996

The characteristics of rapid development of the low pressure system over the East Sea from 06 to 08 Nov., 1995 has been analyzed in detail by the synoptic numerical products and satellite observations. The Low system was initially triggered the development of the baroclinic leaf cloud over the border of the northern part of Korea and China and moved eastward and then developed explosively com-ma or lambda type cloud system over the East Sea. To forecast well the general development and movement of the coastal winter cyclone over the East Sea popularly in a numerical simulation by several scientists, the large baroclinicity, continuous support of water vapor, and sequential cold outbreak over the warm sea surface have been more commonly concerned about. The cyclone which the central surface pressure was dropped 40hPa within 24 hours has often accompanied strong wind and heavy snow- or rain-fall in the winter season. In all successive observations with 12-hourly satellite imagery and analyzed meteorological variables in this period, the centers of the sea-level pressure and 500hPa geopotential height associated with this cyclone were typically illustrated by moving farther eastward using GMS combined enhanced IR images. The maxi-mum wind sustained by this system with the intensity and central pressure of tropical storm was about 60 knots with the center pressure drop of 44hPa/day similar to the North American cyclonic bomb and Atlantic storm.

• 한국해양학회지
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• v.2 no.1_2
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• pp.24-33
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• 1967

The variations of monthly mean sea levels along the coast of Korea anre studied graphic and harmonic methods with the data from 9 tides stations and compared with the variations of atmospheric pressure and the changes in density of sea water measured near some of the stations. The monthly mean sea level generally rises in Summer to Autumn, and falls in Winter to Spring and its range is from 20 cm to 50 cm. The variation of monthly mean sea level is of annual type, having one maximum and one minimum. The semi-range of annual components is 10.5 cm at Pusan and increases to the north in the west coast, to 20.8 cm at Inchon. It's phase is, on the whole, similar for the entire coast with about 210 (middle of August), except at Inchon, 200 . The variation of monthly mean sea level is mainly isostatic, or caused by those of sea water density and atmospheric pressure. Especially, the steric effect is predominant on the south- east coast around Pusan. However, in shallow long bays and estuaries on the west coast, the river runoff effect as well as local wind effect is also considerable. Magnitudes of annual variations at each stations are not constant, but widely variable from year to year. On the east and south coast, especially at Ulneungdo and Pusan the variations are large, which seem to be connected with the shifting of main current axes or current patterns in the offing.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.561-569
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• 2013

EOF analysis of tidal residual derived from 2003~2009 tide data was used to identify the spatio-temporal variability. The effect of sea surface air pressures and winds on the tidal residual was also investigated by the correlation analysis. The first mode accounting for 68 % of the total variance represented concurrent sea level rise or fall, and the second mode accounting for 21 % of the total variance explained alternative sea level rise and fall between West Sea coast and both South Sea and East Sea coasts. While northerly and southerly winds dominated the tidal residual in the eastern coast of Yellow Sea, the effect of sea surface air pressures on the tidal residual increased along the coastal regions from South Sea to East Sea.

• Journal of the Korean Child Neurology Society
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• v.26 no.4
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• pp.227-232
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• 2018

Purpose: Febrile seizure (FS) is the most common type of seizure in children between 6 months to 5 years of age. A family history of febrile seizures can increase the risk a child will have a FS. Yet, prevalence of FS regarding external environment has not been clearly proved. This study attempts to determine the association between prevalence of FS and weather. Methods: This study included medical records from the Korea National Health Insurance Review and Assessment Service. Data were collected from 29,240 children, born after 2004, diagnosed with FS who were admitted to one of the hospitals in Seoul, Korea, between January 2009 and December 2013. During the corresponding time period, data from the Korea Meteorological Administration on daily monitoring of four meteorological factors (sea-level pressure, amount of precipitation, humidity and temperature) were collected. The relationships of FS prevalence and each meteorological factor will be designed using Poisson generalized additive model (GAM). Also, the contributory effect of viral infections on FS prevalence and weather will be discussed. Results: The amount of precipitation was divided into two groups for comparison: one with less than 5 mm and the other with equal to or more than 5 mm. As a result of Poisson GAM, higher prevalence of FS showed a correlation with smaller amount of precipitation. Smoothing function was used to classify the relationships between three variables (sea-level pressure, humidity, and temperature) and prevalence of FS. FS prevalence was correlated with lower sea-level pressure and lower humidity. FS prevalence was high in two temperature ranges (-7 to $-1^{\circ}C$ and $18-21^{\circ}C$). Conclusion: Low sea-level pressure, small amount of precipitation, and low relative air humidity may increase FS prevalence risk.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.12 no.1
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• pp.25-30
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• 1976

In the area of the Far East Asia, cyclones are observed 157ea in winter season during the years(1966-1974). Some of them are most difficult to be forecasted due to the extreme irregulalities, have carried out synoptic analysis. The rapid development of cyclones can be attributed to the descending of cold air mass surrounding the axis of the Jet Stream due to the cyclonic rotation, and the lowering of the Jet axis. The Relationships between upper trough line and max. (or min) axis of upper air temperature on the 700mb contributes to the development of the cyclones.

• Journal of the Korean earth science society
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• v.34 no.4
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• pp.303-312
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• 2013

Typhoon Sanba was selected for describing the Korea Meteorological Administration (KMA) Global Data Assimilation Prediction System (GDAPS) model bias tendency in forecast for the interaction between mid-latitude trough and movement speed of typhoon. We used the KMA GDAPS analyses and forecasts initiated 00 UTC 15 September 2012 from the historical typhoon record using Typhoon Analysis and Prediction System (TAPS) and Combined Meteorological Information System-3 (COMIS-3). Sea level pressure fields illustrated a development of the low level mid-latitude cyclogenesis in relation to Jet Maximum at 500 hPa. The study found that after Sanba entered the mid-latitude domain, its movement speed was forecast to be accelerated. Typically, Snaba interacted with mid-latitude westerlies at the front of mid-latitude trough. This event occurred when the Sanba was nearing recurvature at 00 and 06 UTC 17 September. The KMA GDAPS sea level pressure forecasts provided the low level mid-latitude cyclone that was weaker than what it actually analyzed in field. As a result, the mid-latitude circulations affecting on Sanba's movement speed was slower than what the KMA GDAPS actually analyzed in field. It was found that these circulations occurred due to the weak mid-tropospheric jet maximum at the 500 hPa. In conclusion, the KMA GDAPS forecast tends to slow a bias of slow movement speed when Sanba interacted with the mid-latitude trough.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.27 no.4
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• pp.293-302
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• 1991

The anomalous sea level deviation or storm surge caused by the typhoon Thelma in 1987 are studied analysing tidal observation data at 7 stations in the south coast of Korean peninsula. The surges are calculated by subtracting the predicted tidal height from the observed tidal record. The tidal deviation at these stations along the coast are discussed in association with meteorological data. The sea level anomalies are studied by means of the empirical orthogonal function (EOF) analysis and the fast fourier transform (FFT) method. The results of analysis suggest that the peak value of surges are higher at the tidal stations in semi-enclosed bay and in long narrow channel than at the ones facing with the open sea. From the result of EOF analysis, the temporal and spatial fluctuations of storm surge can be described by the first EOF mode, which explains 63% of the total variances during the passage of typhoon Thelma. The deviation of storm surge in the studied areas indicates bi-modal peak during the passage of typhoon Thelma. From the results of FFT spectrum analysis, the peak of energy of autospectrum for surge, atmospheric pressure, and wind stress appeared at low frequency fluctuations band of 0.008-0.076 cph over the 4 stations. Auto-correlation function of surge showed periodicity, while that of atmospheric pressure and wind stress indicates no periodicity. The result of FFT analysis shows that the typhoon surges are related chiefly with the change of atmospheric pressure in an open bay (Cheju Harbor), but with the wind stress in a semi-enclosed bay (Yeosu Harbor).

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.4
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• pp.344-353
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• 2016

The cause of abnormal tidal residuals was examined by analyzing sea levels, sea surface atmospheric pressures, winds at ten tide stations, and current, measured at the coast of the Yellow Sea from the night of November $24^{th}$ to the morning of the $25^{th}$ in 2013, along with weather chart. Additionally, the cross-correlations among the measured data were also examined. The 'abnormal tidal residuals' mentioned in this study refer to differences between maximum and minium tidal residuals. The largest abnormal tidal residual was identified to be a difference of 176 cm occurring over 4 hours and 1 minute at YeongJongDo (YJD) with a maximum tidal residual of 111 cm and minimum of -65 cm. The smallest abnormal tidal residual was 68 cm at MoSeulPo (MSP) during 8 hours 52 minutes. The cause of these abnormal tidal residuals was not a meteo-tsunami generated by an atmospheric pressure jump but wind generated by the pressure patterns. The flow speed due to these abnormal tidal residuals as measured at ten tide stations was not negligible, representing 16 ~ 41 % of the annual average ebb current speed. From the cross correlation among the tidal residuals, winds, and tidal residual currents, we learned the northern flow, due to southerly winds, raised the sea level at Incheon when a low pressure center located on the left side of the Korean Peninsula. After passing the Korean Peninsula, a southern flow due to northerly winds decreased the sea level.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.4 no.1
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• pp.1-12
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• 1986

An attempt to obtain equipotential surface over the East China Sea along the three SEASAT ground tracks are described. Total correction of sea surface heights above the reference ellipsoid provided by SEASAT GDR Altimeter data consists of ocean tides and surges, body tides, sea level pressure inverse barometer effect corrections for the present study. It was shown that three equipotential surface derived from the corrections were qualitatively in agreement with GEM l0B Model and SS3 Mean Sea Surface Model.

• Journal of the Korean Association of Geographic Information Studies
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• v.2 no.1
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• pp.12-31
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• 1999

Topex/Poseidon satellite altimetric data are used to estimate characteristics on the oceanic and atmospheric correction factors, and the mean sea level and its variations in the Yellow Sea, the East China Sea and the East Sea from September 1992 through August 1994(70cycles). For the atmospheric correction factors, the variations of dry troposphere, humid troposphere, ionosphere and inverted barometer were very small as a few centimeters, but the variations of electromagnetic bias were higher than other factors. For the oceanic correction factors, the variations of ocean tide(35cm in track 127 and 60cm in track 214) showed high ranges compared to elastic tide(5cm in track 127 and 1cm in track 214) and loading tide(1.8cm in track 127 and 1cm in track 214). It should be understood that the variations of ocean free surface is mainly under the influence of, firstly, ocean tide and, secondly, electromagnetic bias. Mean sea level in the Yellow Sea are higher than in the rest of Seas. Then its range generally comprised between -60cm and 210cm with mean value of about 100cm. Also its variations showed high values in the Yellow Sea and East China Sea, especially 5.689cm in Youngampo. This result is mainly due to the effects of local topography and tidal current.