• 한국해안·해양공학회논문집
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• 제26권6호
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• pp.352-358
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• 2014

국내 서해안과 남해안의 조위자료로부터 조석-해일 비선형효과에 대한 발생실태를 조사한 결과 부산을 제외한 모든 해역에서 비선형성이 확인되고 있으며 특히 목포 및 완도를 중심으로 한 서남해안에서 두드러지게 나타나고 있다. 대규모 해일이 드물기 때문에 창조집중에 대한 사례는 흔치 않은 반면 저조시 조위편차가 커지는 조석변조해일은 빈번하게 발생하고 있다. 또한 낙조우세가 심한 목포해역의 경우 새로운 형태의 조석-해일 비선형성에 의해 낙조시 해일고가 크게 나타나는 현상을 확인하였다. 조위편차 산정과정에서 비선형성과 관련된 오류를 해소하는 방안으로 편기해일고 산정방법에 대해서도 검토하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.744-747
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• 2006

The sea level of the Java Sea is reproduced using HYbrid Coordinate Ocean Model (HYCOM) setting up in the horizontal grid from $100^{\circ}E$ to $125^{\circ}E$ and from $10^{\circ}S$ to $8^{\circ}N$. The model is initialized by ocean temperature and salinity profiles from Levitus 1998 and forced by the atmospheric field derived from NCEP reanalysis. In this research HYCOM is applied to explain the El $Ni{\tilde{n}}o$ Southern Oscillation (ENSO) impacts on the sea level of the Java Sea. The monthly tide gauge sea level data are produced based on hourly sea level data from 1993 to 1997. Altimeter sea level data are based on weekly merged products between TOPEX/Poseidon and ERS absolute dynamic topography (ADT). The simulated sea level both HYCOM and ADT agree well with the tide gauge sea level. The sea level of the Java Sea is high during the La $Ni{\tilde{n}}a$ period and low during the El $Ni{\tilde{n}}o$ period.

• 한국환경과학회지
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• 제11권11호
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• pp.1141-1147
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• 2002

Based on the tide gauge data from the Permanent Service for Meau Sea Level (PSMSL) collected at 23 locations in the Korean coast, the long-term sea-level trend was computed using a simple linear regression fit over the recorded length of the monthly mean sea-level data. The computed sea-level trend was also corrected for the vertical land movement due to post glacial rebound(PGR) using the ICE-4G(VM2) model output. It was found that the PGR-corrected sea-level trend near Korea was 2.310 $\pm$ 2.220 mm/yr, which is higher than the global average at 1.0∼2.0mm/yr, as assessed by the Intergovernmental Panel on Climate Change(IPCC). The regional distribution of the long-term sea-level trend near Korea revealed that the South Sea had the largest sea-level rise followed by the West Sea and East Sea, respectively, supporting the results of the previous study by Seo et al. However, due to the relatively short record period and large spatial variability, the sea-level trend from the tide gauge data for the Korean coast could be biased with a steric sea-level rise by the global warming during the 20th century.

• 한국GIS학회:학술대회논문집
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• 한국GIS학회 2003년도 공동 춘계학술대회 논문집
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• pp.108-111
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• 2003

Altimeter data from the Topex/Poseidon (T/P) were analyzed to study the sea surface circulation and its variability in the North East Asian Seas. Long term averaged T/P sea level time series data where compared with in situ sea level measurements from a float-operated type tide gauge around of south Korea and Japan. Tf data are a large contaminated by 60-day tidal aliasing effect, very near the alias periods of M2 and S2. When this 60-day effect is removed, the data agree well with the tide gauge data with 4.6 cm averaged RMS difference. The T/P derived sea level variability reveals clearly the well-known, strong current-topography such as Kuroshio. The T/P mean sea level of North Pacific (NP) was higher than Yellow Sea (YS) and East Sea (ES). The T/P sea level variability, with strong eddy and meandering, was the largest in eastern part of Japan and this variability was mainly due to the influence of bottom topography in Kuroshio Extension area.

• Ocean and Polar Research
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• 제36권3호
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• pp.225-234
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• 2014

The 2011 Tohoku earthquake triggered extremely destructive tsunami waves which propagated over the Pacific Ocean, Atlantic Ocean through Drake Passage and Indian Ocean respectively. A total of 10 tide-gauge records collected from the UNESCO/IOC site were analyzed through a band-pass digital filtering device to examine the observed tsunami characteristics. The ray tracing method and finite-difference model with GEBCO 30 arc second bathymetry were also applied to compare the travel times of the Tohoku-originated tsunami, particularly at Rodrigues in the Indian Ocean and King Edward Point in the Atlantic Ocean with observation-based estimates. At both locations the finite-difference model produced the shortest arrival times, while the ray method produced the longest arrival times. Values of the travel time difference however appear to be within tolerable ranges, considering the propagation distance of the tsunami waves. The observed tsunami at Rodrigues, Mauritius in the west of the Madagascar was found to take a clockwise travel path around Australia and New Zealand, while the observed tsunami at King Edward Point in the southern Atlantic Ocean was found to traverse the Pacific Ocean and then passed into the Atlantic Ocean through the Drake Strait. The formation of icebergs captured by satellite images in Sulzberger in the Antarctica also supports the long-range propagation of the Tohoku-originated tsunami.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 추계종합학술대회
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• pp.300-303
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• 2001

The first 7 years of altimeter data from the TOPEX/POSEIDON (T/P) were analyzed to study the surface circulation and its variability in the East Asian Marginal Seas. Long term averaged T/P sea level time series data where compared with in situ sea level measurements from a float-operated type tide gauge around of south Korea and Japan. T/P data are a large contaminated by 60-day tidal aliasing effect, very near the alias periods of M2 and S2. When this 60-day effect is removed, the data agree well with the tide gauge data with 4.6 cm averaged RMS difference. The T/P derived sea level variability reveals clearly the well-known, strong current-topography such as Kuroshio. The T/P mean sea level of North Pacific (NP) was higher than Yellow Sea (YS) and East Sea (ES). The T/P sea level valibility, with strong eddy and meandaring, was the largest in eastern part of Japan and this variability was mainly due to the influence of bottom topography in Kuroshio Extention area.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 추계학술발표회
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• pp.219-225
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• 2003

The present study intends to assess the long-term steric sea-level change and its prediction, and potential impacts to the sea-level rise due to the 21st global warming in the coastal zone of the Korea in which much socioeconomic activities have been occurred. The analysis of the 23 tide-gauge data near Korea reveals the overall mean sea-level trend of 2.31 mm/yr.In the satellite altimeter data (Topex/Poseidon and ERS), the sea-level trend in the East Sea is 4.6mm/yr. Both are larger than those of the global average value. However, it is quite questionable that the sea-level trends with the tide-gauge data on the neighboring seas of Korea relate to global warming because of the relatively short observation period and large spatial variability. It is also not clear whether the high trend of altimeter data in the East Sea is related to the acceleration of sea level rise in the Sea, short response time of the Sea, natural variability such as decadal variability, short duration of the altimeter. The coastal zone of Korea appears to be quite vulnerable to the 21st sea level rise such that for the I-m sea level rise with high tide and storm surge, the inundation area is 2,643 km2, which is about $1.2\%$ of total area and the population in the risk areas of inundation is 1.255 million, about $2.6\%$ of total population. The coastal zone west of Korea is appeared to be the most vulnerable area compared to the east and south. In the west of the Korea, the North Korea appears to be more vulnerable than South Korea. In order to cope with the future possible impact of sea-level rise to the coastal zone of Korea effectively, it is essential to improve scientific information in the sea-level rise trend, regional prediction, and vulnerability assessment near Korean coast.

• Ocean and Polar Research
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• 제24권3호
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• pp.249-253
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• 2002

There is a great deal evidence concerning crustal uplift, after deglaciation, in the vicinity of Syowa Station $(69^{\circ}S,\;39^{\circ}E)$ from tide gauge data, seismic evidence, raised beaches, marine terraces, etc. The geomorphological and tide gauge data show that the crustal uplift is going on around Syowa Station. Seismic observations at Syowa Station started in 1959. Phase readings of the earthquakes have been published by National Institute of Polar Research once a year since 1968, as one of the Data Report Series. Eighteen local earthquakes were detected on short period seismograms at Syowa Station in 1990-2000. The seismicity during the period from 1990 to 2000 was lower than that from 1987 to 1989 when epicenters of local earthquakes were determined by tripartite seismic array. Local earthquake activity corroborates the crustal uplif4 which is an intermittent phenomenon. Sea level falling of 4.5 mm/y was found using data in 1975-1992. This felling rate is consistent with the geomorphological data. A route for repeat leveling survey was established in East Ongul Island. No appreciable change of sea level was observed for the last 14 years. A dynamics of the crustal uplift around Syowa Station has been discussed using geomorphological data, ocean tide, and seismic and leveling data, which is estimated to be an intermittent phenomenon. When local seismic activity is high, the crustal uplift is estimated to be going on. On the contrary, the crustal uplift is in dormancy when the local seismicity is low. Repeated leveling measurements suggest no significant changes, which further supports the idea that the crustal uplift in offshore is not a tilt trend movement but a block movement.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 춘계종합학술대회
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• pp.645-647
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• 2003

쓰시마섬의 Izuhara에서 1년간 조사된 조위자료를 가지고 에너지 스펙트럼을 구하였다. 이때 에너지 스펙트럼은 관성주기와 100시간주기 사이에서 높게 나타났다. 본 연구에서 나타낸 간단한 해석적 모델에서도 높은 에너지 스펙트럼이 쓰시마섬 주변 대륙사면을 따라서 전파되는 파와 관계한다는 것을 보여준다. 즉, 이러한 높은 에너지 스펙트럼으로부터 대륙붕파의 존재를 명확히 파악할 수 있다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.312-316
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• 2002

Satellite radar interferometry data shows a strong coherent signal on oyster sea farms where artificial structures installed on the bottom. We obtained 21 highly coherent interferograms from eleven JERS-1 SAR data sets despite of large orbital baseline (~2 km) or large temporal baseline (~l year). The phases observed in sea farms are probably induced by double bouncing on sea surface, and consequently reveal a tide height variation. To restore the absolute sea level changes we counted the number of wrapping by exploiting the intensity of backscattering. Backscattering intensity is closely correlated with the change in water surface height, while interferometry gives the detailed variation within the limit of 2$\pi$ (or 15.3 cm). Comparing the radar measurements with the tide gauge records yielded a correlation coefficient of 0.96 and an ms error of 6.0 cm. The results demostrate that radar interferometry is promising to measure sea level.