• 제목/요약/키워드: tide gauge sea levels

검색결과 12건 처리시간 0.032초

Comparison of Topex/Poseidon sea surface heights and Tide Gauge sea levels in the South Indian Ocean

  • Yoon, Hong-Joo
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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    • pp.70-75
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    • 1998
  • The comparison of Topex/Poseidon sea surface heights and Tide Gauge sea levels was studied in the South Indian Ocean after Topex/Poseidon mission of about 3 years (11- 121 cycles) from January 1993 through December 1995. The user's handbook (AVISO) for sea surface height data process was used in this study Topex/Poseidon sea suface heights ($\zeta$$^{T/P}$), satellite data at the point which is very closed to Tide Gauge station, were chosen in the same latitude of Tide Gauge station. These data were re-sampled by a linear interpolation with the interval of about 10 days, and were filtered by the gaussian filter with a 60 day-window. Tide Gauge sea levels ($\zeta$$^{Argos}$, $\zeta$$^{In-situ}$ and $\zeta$$^{Model}$), were also treated with the same method as satellite data. The main conclusions obtained from the root-mean-square and correlation coefficient were as follows: 1) to Produce Tide Gauge sea levels from bottom pressure, in-situ data of METEO-FRANCE showed very good values against to the model data of ECMWF and 2) to compare Topex/Poseidon sea surface heights of Tide Gauge sea levels, the results of the open sea areas were better than those of the coast and island areas.

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남인도양에서의 Topex/Poseidon sea surface heights와 tide gauge sea levels간의 비교 (Comparison of Topex/poseidon Sea Surface Heights with Tide Gauge Sea Levels in the South Indian Ocean)

  • 윤흥주
    • 한국수산과학회지
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    • 제32권3호
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    • pp.368-373
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    • 1999
  • Topex/Poseidon sea surface heights are compared to tide gauge sea levels in the South Indian Ocean in the period of January 1993 to December 1995. A user's handbook (AVISO) for processing sea surface height data was used in this study. Topex/Poseidon sea surface heights were obtained from satellite data at the proximity of tide gauge stations. These data were reproduced by a linear interpolation with the interval of 10 days and were processed by the Gaussian filter with a 60-day window. The tide gauge sea levels were obtained in the same manner as the satellite data. The main results on RMS (Root-Mean-Square) and CORR (CORRelation coefficient) in our study were shown as follows: 1) on the characteristics between two data (in-situ and model data), the results (RMS=2.96 cm & CORR=$92\%$ in the Amsterdam plateau, and RMS=3.45 cm & CORR=$59\%$ in the Crozet plateau) of the comparison of Topex/Poseidon sea surface heights with tide gauge sea levels, which was calculated by in-situ data of obsewed station showed generally low values in RMS and high values in CORR against to the results (RMS=4.69 cm & CORR=$79\%$ in the Amsterdam plateau, and RMS= 6.29 cm & CORR= $49\%$ in the Crozet plateau) of the comparison of Topex/Poseidon sea surface heights with tide gauge sea levels, which was calculated by model data of ECMWF (European Center for Medium-range Weather Forecasting), and 2) on the characteristics between two areas (Kerguelen plateau and island), the results (RMS=3.28 cm & CORR= $54\%$ in the Kerguelen plateau) of open sea area showed low values in RMS and high values in CORR against to the results (RMS= 5.71 cm & CORR=$38\%$ in the Kerguelen island) of coast area, respectively.

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남인도양에서의 해수면에 대한 위성자료(Topex/Poseidon 고도계)와 현장자료(Tide Gauge 해면계)간의 비교 (Comparison of Topex/Poseidon sea levels data and Tide Gause sea levels data from the South Indian Ocean)

  • 윤홍주;김상우;이문옥;박일흠
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2001년도 추계종합학술대회
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    • pp.281-285
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    • 2001
  • According to standard procedures as defined in the users handbook for sea level data processes, I was compared to Topex/poseidon sea level data from the first 350days of mission and Tide Gauge sea level data from the Amsterdam- Crozet- Kerguelen region in the South Indian Ocean. The comparison improves significantly when many factors for the corrections were removed, then only the aliased oceanic tidal energy is removed by oceanic tide model in this period. Making the corrections and smoothing the sea level data over 60km along-track segments and the Tide Gauge sea level data for the time series results in the digital correlation and RMS difference between the two data of c=-0.12 and rms=11.4cm, c=0.55 and rms=5.38cm, and c=0.83 and rms=2.83cm for the Amsterdam, Crozet and Kerguelen plateau, respectively. It was also found that the Kerguelen plateau has a comparisons due to propagating signals(the baroclinic Rossby wave with velocity of -3.9~-4.2cm/sec, period of 167days and amplitude of 10cm) that introduce temporal lags($\tau$=10~30days) between the altimeter and tide gauge time series. The conclusion is that on timescales longer than about 10days the RMS sea level errors are less than or of the order of several centimeters and are mainly due to the effects of currents rather than the effects of sterics(water temperature, density) and winds.

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Relative Sea-level Change Around the Korean Peninsula

  • Jeon, Dong-Chull
    • Ocean and Polar Research
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    • 제30권4호
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    • pp.373-378
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    • 2008
  • Long-term tide-gauge data from around the Korean Peninsula were reanalyzed. Both the coastal water and the open sea surrounding the Korean Peninsula appeared to have been influenced by global warming. The long-term change in relative sea levels obtained from tidal stations showed a general rising trend, especially near Jeju Island. It is proposed that global warming may have caused shifting of the path of the Kuroshio branch (Tsushima Warm Current) toward Jeju Island, causing a persistent increase in the water levels along the coast of the island over the last few decades.

남인도양의 해수면 변화 특성 (Characteristics on sea level variations in the South Indian Ocean)

  • 윤홍주
    • 한국정보통신학회논문지
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    • 제5권6호
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    • pp.1094-1103
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    • 2001
  • 남인도양의 암스테르담- 크호제트- 케르겔른 지역에서의 Topex/Poseidon의 고도계 자료와 Tide Gauge의 해면계 자료를 상호 비교 및 검정하였다. 8개 주요 조석성분들의 진폭의 변통성과 관련하여 해양조석모델의 결과와 조화분해해석의 결과간의 미소한 차이는 궁극적으로 수온, 밀도 및 바람보다는 주로 남극순환해류의 흐름에 영향을 받다. 두 자료간의 상관관계(correlation coefficient)와 편차(rms)를 보면, 암스테르담 대지지역에서는 c=-0.12 및 rms=11.40cm, 크호제트 대지지역에서는 c=0.05 및 rms=5.38cm, 케르겔른 대지지역에서는 c=0.83 및 rms=2.83cm로 그리고 케르겔른 해안지역에서는 c=0.24 및 rms=6.72cm로 각각 나타났다. 이 중 케르겔른 대지지역이의 높은 상관성은 해안지역으로부터 멀어질수록 정도 높은 고도계의 자료를 획득할 수 있다는 것을 의미한다. 케르겔른 해안지역과 케르겔른 대지지역의 해수면의 변화의 특성은 2일 상의 장주기에 대해서는 상호 높은 상관성과 함께 유사한 해수면의 변화를 가진다. 케르겔른 대지지역 내에서는 유속이 -3.9~-4.2cm/sec이고 주기가 167days 그리고 진폭이 10cm인 바로크리닉 로쓰비파가 서쪽으로 전파한다.

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황해 동부 연안의 홀로세 해수면 변화: 대리기록과 관측자료를 통한 재검토 (Holocene Sea Level Changes in the Eastern Yellow Sea: A Brief Review using Proxy Records and Measurement Data)

  • 이은일;장태수
    • 한국지구과학회지
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    • 제36권6호
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    • pp.520-532
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    • 2015
  • 황해 동부 해안의 홀로세 해수면 변동 특성을 이해하고 시기 별 상승추세를 비교하기 위하여 지질학적 대리기록과 기기관측 자료를 통합하여 분석하였다. 홀로세 동안 황해의 해수면은 초기에 약 10 mm/yr의 속도로 빠르게 상승하고 중기를 거쳐 후기로 갈수록 해수면 상승률은 1 mm/yr 정도로 둔화되며, 20세기 해수면은 홀로세 후기보다 다소 빠르게 상승하였다. 빠른 상승으로 알려진 현재 해수면 상승률은 홀로세 초기와 중기의 상승추세와 비교할 때 사실 훨씬 낮거나 비슷하게 나타난다. 최근 조위계 자료는 황해 해수면이 21세기로 갈수록 상승률이 높아지고 있음을 나타낸다. 이러한 상승 추세는 전 지구적 해수면 변화와 일치한다. 추가적으로, 연구지역에서 현재의 해수면 상승 추세는 이산화탄소 농도와 해수표층온도의 증가율과 대비되며, 이는 인간활동에 수반된 지구온난화의 신호이다. 그러므로 황해 동부와 전세계의 해양에서 관찰되는 현 지구온난화에 의해 야기된 해수면 변화를 '인류세' 해수면 변화라고 제안한다. 이 해수면변화는 조위계와 인공위성 고도계 같은 기기관측을 기반으로 하며, 계측시대를 의미한다. 이와 같이, 황해의 홀로세 해수면 변동은 대리기록으로, '인류세' 해수면은 기기관측을 기반으로 한다.

Status of Observation Data at Ieodo Ocean Research Station for Sea Level Study

  • Han, MyeongHee
    • 한국지구과학회지
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    • 제41권4호
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    • pp.323-343
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    • 2020
  • Observation data measured at Ieodo Ocean Research Station (IORS) have been utilized in oceanographic and atmospheric studies since 2003. Sea level data observed at the IORS have not been paid attention as compared with many other variables such as aerosol, radiation, turbulent flux, wind, wave, fog, temperature, and salinity. Total sea level rises at the IORS (5.6 mm yr-1) from both satellite and tide-gauge observations were higher than those in the northeast Asian marginal seas (5.4 mm yr-1) and the world (4.6 mm yr-1) from satellite observation from 2009 to 2018. The rates of thermosteric, halosteric, and steric sea level rises were 2.7-4.8, -0.7-2.6, 2.3-7.4 mm yr-1 from four different calculating methods using observations. The rising rate of the steric sea level was higher than that of the total sea level in the case with additional data quality control. Calculating the non-steric sea level was not found to yield meaningful results, despite the ability to calculate non-steric sea level by simply subtracting the steric sea level from total sea level. This uncertainty did not arise from the data analysis but from a lack of good data, even though tide, temperature, and salinity data were quality controlled two times by Korea Hydrographic and Oceanography Agency. The status of the IORS data suggests that the maintenance management of observation systems, equipment, and data quality control should be improved to facilitate data use from the IORS.

해수면 변화와 해안 침식 (Sea-level Change and Coastal Erosion)

  • Jeon, Dong-Chull
    • 한국해안해양공학회지
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    • 제7권4호
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    • pp.289-304
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    • 1995
  • 북태평양에서 선택한 조석 정점에서 상대 해수면의 시계열 자료와 하와이 제도에서 해안선 변화의 항공 사진을 분석하였다. 대부분의 정점에서 해면의 장기적 상승 추이는 +1 내지 +5 mm/yr의 범위를 보이는데, 주로 지구 온난화 및 지질학적 판(plate)의 이동에 의해 나타나고 있다. 해면의 연변화 및 수년 주기의 변화는 각각 태양 복사의 연변화에 의한 표층수의 팽창 및 수축과, ENSO 주기와 관계된 대기-해양의 상호작용으로부터 기인한다. 이러한 세 가지의 다른 시간 규모로 발생하는 해면변화(장기적 해면상승 추이, 연변화, 수년주기 변화)가 장기적으로 이안 퇴적물 수송의 결과로서 나타나는 해안선 변화에 어떻게 정량적으로 기여하는지 추정하는 가설이 제시된다.

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베이지안 다중 비교차 분위회귀 분석 기법을 이용한 비정상성 빈도해석 모형 개발 (A Development of Nonstationary Frequency Analysis Model using a Bayesian Multiple Non-crossing Quantile Regression Approach)

  • 오랑치맥 솜야;김용탁;권영준;권현한
    • 한국연안방재학회지
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    • 제4권3호
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    • pp.119-131
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    • 2017
  • Global warming under the influence of climate change and its direct impact on glacial and sea level are known issue. However, there is a lack of research on an indirect impact of climate change such as coastal structure design which is mainly based on a frequency analysis of water level under the stationary assumption, meaning that maximum sea level will not vary significantly over time. In general, stationary assumption does not hold and may not be valid under a changing climate. Therefore, this study aims to develop a novel approach to explore possible distributional changes in annual maximum sea levels (AMSLs) and provide the estimate of design water level for coastal structures using a multiple non-crossing quantile regression based nonstationary frequency analysis within a Bayesian framework. In this study, 20 tide gauge stations, where more than 30 years of hourly records are available, are considered. First, the possible distributional changes in the AMSLs are explored, focusing on the change in the scale and location parameter of the probability distributions. The most of the AMSLs are found to be upward-convergent/divergent pattern in the distribution, and the significance test on distributional changes is then performed. In this study, we confirm that a stationary assumption under the current climate characteristic may lead to underestimation of the design sea level, which results in increase in the failure risk in coastal structures. A detailed discussion on the role of the distribution changes for design water level is provided.