• Title/Summary/Keyword: Tidal

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Overview of Tidal Phase-lag References Used in Korea (우리나라 조석지각 기준 표기에 대한 고찰)

  • Byun, Do-Seong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.12 no.3
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    • pp.234-238
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    • 2007
  • Three different tidal phase-lag references have been used by the tidal research community of Korea: Greek kappa (k), Local standard time zone ($135^{\circ}E$) phase-lag (g) and Greenwich phase-lag (G). This ununified tidal information system may induce confusion in understanding tidal characteristics and their variability and impede the development of tidal knowledge in Korea. In this study we closely explore the three phase-lag reference definition with respect to their mutual conversion. We also identify an incorrect phase-lag reference definition used in previous works and discuss what has led to this misunderstanding.

Bathymetric and Topographic Changes of the Gomso-Bay Tidal Flat, West Coast of the Korean Peninsula (한반도 서해안 곰소만 갯벌의 수심 및 지형 변화)

  • Jin Ho Chang;Yong-Gil Kim;Myong Sun Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.6
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    • pp.552-561
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    • 2023
  • The seafloor topography of Gomso Bay on the west coast of Korea was investigated using subtidal bathymetry and tidal-flat altimetry. Gomso Bay consists of 80% tidal flats and 20% subtidal zone, and is divided into an outer bay and an inner bay by the Jujincheon esturary channel. The outer bay tidal flat, has few tidal channels, has a concave topographic profile, and is characterized by the development of chenier and intertidal sand bars, giving it the appearance of gently sloping, dissipative beaches. The inner bay tidal flat has wide upper and middle tidal flats with a well-developed tidal channel system without cheniers. Moreover, the topographical cross-section between these tidal channels is convex upward, and shows the characteristics of a depositional environment greatly influenced by tidal channels and tidal action. An analysis of the horizontal movement of the tidal flat environment over the past 37 years investigating changes in the iso-depth lines in the Gomso-Bay tidal flat between 1981 and 2018 revealed that the Gomso-Bay tidal flat retreated gradually landward. As a result of analyzing the erosion and sedimentation characteristics of Gomso Bay, assuming that most of the water depth changes were due to changes in the elevation of the sea floor and sea level, an average of 1 cm (0 mm/y) of sediment was eroded in the outer bay over the past 37 years (1981-2018), In the inner bay, an average of 50 cm (14 mm/y) was deposited. Notably, the high tidal flats of the outer bay were largely eroded. Monitoring photographs of the coast showed that most of the erosion of the high tidal flats in the outer bay occurred in a short period around 1999 (probably 1997-2002), and that the erosion resulted from the erosion of sand dunes and high-tide beaches caused by temporarily greatly raised high tide levels and storms.

Spatial Distribution of Tidal Flats in Korea (한국(韓國)의 간석지(干潟地) 분포(分布))

  • Jo, Myung-Hee;Jo, Wha-Ryong
    • Journal of the Korean association of regional geographers
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    • v.3 no.2
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    • pp.195-208
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    • 1997
  • On the basis of the topographic maps in the 1910's and 1990's and the classification map of Landsat TM satellite image photographed on Sept 1, 1996, the spatial distribution and the current situation concerning tidal flats in Korea were studied by measuring the area with GIS Arc/Info system and examining the regional condition required to develop the tidal flats. The results are as follow; The tidal flat resources in Korea cover an area of about 3800 square meters, including the reclaimed one since the 1910's. And they are widely distributed in the west coast of South Jeonla, Kyunggi bay, Asan bay, the south coast of South Jeonla, Kunsan bay, Chunsoo bay, and the coast of South Kyungsang and Pusan when put in the order from bigger area. Given the area under the construction at present, more than 50% of the tidal flats are reclaimed ones. The tidal flats are being developed especially in Kyunggi and Asan bays because they perfectly measure up to the conditions required. For Kunsan bay, a remarkably good supply system of the alluvial sedimentary materials and a favorable coastline requirement for the coast of the South Jeonla also contribute to the development of the tidal flats. In the case study of Kunsan bay, it was shown that the shape of the tidal flat is making a continuous change and the area is getting bigger in terms of the multi-temporal change of the tidal flat development. However, while in the first half of the 20th century, the increasing rate of the area was considered to be rather high, it is considerably lowered almost to a standstill in the latter half of the century.

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The Development of 10 kW Class Tidal Power Generator System - Focusing on Field Experiments with Pipelines (10 kW급 조력발전장치 개발 - 관수로 현장실험을 중심으로)

  • HyukJin Choi;Nam-Sun Oh;Dong-Hui Ko;Shin Taek Jeong
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.35 no.1
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    • pp.1-12
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    • 2023
  • Along with the growing interest in renewable energy development, Korea's west coast is one of the favorable regions for tidal power. Tidal power using tidal barrages that work like hydroelectric dams is a representative method of tidal power through long-term operation, but the promotion of tidal power projects is being delayed or stopped due to impacts on ecological changes, reproduction, water column processes and hydrology. In order to reduce the high construction cost and environmental cost problems caused by tidal power using tidal barrages, in this study, field experiments were conducted to develop and verify the performance of tidal power generation devices applicable to sea areas where dykes are already installed. As a result of conducting five cases of experiments using two water tanks, pipe lines, open channels, and water turbine and generator, the possibility of developing a power generation system capable of generating more than 10 kW output and more than 60% efficiency were confirmed. The results of this study can be used for small-scale tidal power by utilizing the existing dykes of the west coast.

A Study on Power System Characteristics by Installing SIHWA Tidal Power Plant (시화호 조력발전소 운전에 따른 전력계통 특성 분석에 관한 연구)

  • Kim, Kyu-Ho;Song, Kyung-Bin;Kim, Sang-Min;Choi, Hong-Seok
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.254-255
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    • 2011
  • This paper presents a method to analysis the effect for integrating Sihwa tidal power into power systems. Especially, power flow, fault current, voltage and contingency of sihwa tidal power plant area are calculated and the generation characteristics of tidal machine are analyzed.

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A Study on Assessment of Tidal Stream Resources (조류자원의 평가에 관한 연구)

  • Yang, Chang-Jo;Choi, M.S.;Lee, Y.H.
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2011.06a
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    • pp.309-309
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    • 2011
  • This paper outlines extraction potential of tidal stream resources from the simplified channel in which flow is driven by a head difference between inlet and outlet. Energy extraction alters the flow within a simple channel, and extraction of 10% energy flux in a natural channel would give rise to a flow speed reduction of about 5.7%.

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A study on the tidal phenomena of Nagdong River-mouth - Tidal fluctuations of Nagdong River - (낙동강 하구 호석에 관한 조사연구(I)- 낙동강의 조위변동 -)

  • 양윤모;김탁부
    • Proceedings of the Korea Water Resources Association Conference
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    • 1982.07a
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    • pp.3-24
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    • 1982
  • The relations between tidal fluctuation and freshwater discharge are stuied dy use of observed data in the estuarine region of the Nagdong Rivre. Damping modulus which represents the resistance to propagation of tidal wave is estimated, and it is verified that when the fresh water discharge is lower than 300 m/sec., the elevation of mean-water-level at Gupo is the same as mean sea-water-level.

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Tidal Computations For Inchon Bay

  • Choi, Byung Ho
    • 한국해양학회지
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    • v.15 no.2
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    • pp.112-122
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    • 1980
  • A two-dimensional non-linear tidal model has been established to calculate the M$\_$2/ tide of Inchon Bay in the west coast of Korea. Cartesian coordinates are used for the derivation of the governing equations and account is taken of extensive drying boundaries (tidal flats) which are exposed at low tides. The tidal amplitudes and phases computed from the model agree well with those known from observation lying within bounds 5cm in amplitude and 5 in phase relative to the observed results. The work represents a further stage in the development including extensive sea measurements capable of application in various coastal engineering problems encountered in Inchon Bay area.

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Refinement of the Global Ocean Tidal Charts (전구해양 조석도의 개선)

  • Park, Byung-Ho;Kexiu Liu;Ji Wang
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2000.09a
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    • pp.176-181
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    • 2000
  • This paper briefly outline the approach we are now setting for improving the existing global ocean tidal charts in next few years. There has been notable progress in predicting global ocean tide in mid 90s to improve correction procedures for tidal signals in altimetry with more accurate tidal models (http://podaac.jpl.nasa.gov/) than existing ones. (omitted)

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The comparison of tidal power generation methods at Sukmodo (강화도 석모도 지역에서의 효율적인 조력발전방식 비교)

  • Lee, Tae-Hoon;Sim, Ju-Yeol;Cho, Yong-Sik
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.435-438
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    • 2008
  • The huge economical damage and environmental pollution have been occurred for decades because of using of fossil fuel. So the development of alternative energy is urgent. In the west sea of Korea, a proper area for tidal power plant, development and investigation for economical efficient of tidal power plant are preceeding. The water turbine generator with the capacity of 25.4MW was used to compare single-basin flood tide generation with ebb tide generation while considering the water depth and tide in the vicinity of Sukmodo.

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