• 제목/요약/키워드: Tide land

검색결과 125건 처리시간 0.024초

경기만 갯벌의 지표면 토지피복 변화가 국지기상에 미치는 영향 평가 (Impacts of Land Cover Change of Tidal Flats on Local Meteorology in Gyeonggi Bay, West Sea of Korea)

  • 안혜연;김유근;정주희
    • 대기
    • /
    • 제27권4호
    • /
    • pp.399-409
    • /
    • 2017
  • The impact of land cover changed by tidal flats on local meteorology in Gyeonggi Bay was quantitatively evaluated based on a numerical modeling approach during 18 days (21 June to 9 July 2013). The analysis was carried out using three sets of simulation scenarios and the land cover of tidal flats for each simulation was applied as follows: (1) the herbaceous wetland representing coastal wetlands (i.e., EXP-BASE case), (2) the barren or sparsely vegetated representing low tide (i.e., EXP-LOW case), (3) the water bodies representing high tide (i.e., EXP-HIGH case). The area of tidal flats was calculated as about $552km^2$ (the ratio of 4.7% for analysis domain). During the daytime, the change (e.g. wetlands to water) of land cover flooded by high tide indicated the decrease of temperature (average $3.3^{\circ}C$) and the increase of humidity (average 13%) and wind speed (maximum $2.9m\;s^{-1}$). The changes (e.g. wetlands to barren or sparsely vegetated) of land cover induced by low tide were smaller than those by high tide. On the other hands, the effects of changed land cover at night were not apparent both high tide and low tide. Also, during the high tide, the meteorological change in tidal flats affected the metropolitan area (about 40 km from the tidal flat).

Monitoring Activities of Permanent GPS Stations at Tide Gauge in South Korea

  • Won, Ji-Hye;Park, Kwan-Dong;Kim, Sang-Ho
    • 한국항해항만학회:학술대회논문집
    • /
    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
    • /
    • pp.525-528
    • /
    • 2006
  • South Korea has about 80 permanent GPS stations, being used for a variety of applications such as DGPS, RTK, survey and geodesy. Some of them are installed in or near the coastal area for the purpose of maritime navigation. But, until recently, none of them are used for tide gauge benchmark monitoring. In order to monitor the absolute sea level changes, it is necessary to monitor the land uplift or subsidence occurring at tide gauge sites. It is a common practice to use GPS stations installed at tide gauges to determine absolute sea level. This collaborative efforts coordinated by IGS are called TIGA Pilot Project. Many countries including U.S., Canada, European Union nations, Australia and Japan are participating in TIGA, but South Korea is not a member yet. Recently, we established continuously operating GPS stations at tide gauges located in Incheon and Jeju to monitor the movement of tide gauges sites. This paper will introduce goals and progress of the efforts.

  • PDF

Estimation of Sea Surface Temperature Change by Tide Embankment Construction

  • Shin Dong-hoon;Lee Kyoo-seock
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
    • /
    • pp.146-148
    • /
    • 2005
  • This study investigates to detect sea surface temperature (SST) and land cover change after tide embankment construction using Landsat Thematic Mapper (TM) thermal infrared (TIR) band data at Shihwa Lake and surrounding area. SST measurement is important for studies of both the structure of the ocean and as the thermal boundary between the ocean and the atmosphere. The TIR band of TM images can be used to detect SST change whose shoreline is complicated and narrow like the study site. The purpose of this study is to estimate SST and land cover change at Shihwa Lake and surrounding area.

  • PDF

간척사업(干拓事業)의 다기능적(多機能的) 편익(便益)-비용분석(費用分析)과 발전방향(發展方向) (Multi-functional Benefits & Costs Analysis of Tide Land Reclamation Project and Development Guidelines in the Future)

  • 임재환
    • 농업과학연구
    • /
    • 제32권2호
    • /
    • pp.107-126
    • /
    • 2005
  • The most limited production resource in Korea is land. During the period from 1995 to 2002, annual farm land area of 17,600ha have been converted to urban and industrial land. The self-sufficiency rate of rice, Korean staple food, is expected to be decreased from 97.5% in 2003 to 60-70% in 2020. Under such conditions, this study is aimed at first identifying multi-functional benefits of the reclamation projects such as agricultural production, industrial water supply, urban land supply, transportation effects, sightseeing effects and environmental values with and without the projects. To carry out the objectives, three existing tideland reclamation projects such as Daeho, Kumgang and Yongsangang irrigation project stage II were evaluated and Saemangeum tideland reclamation project which was jointly revaluated by environmental NGO and Govn't appointed specialists in 2000 was reviewed. According to this study results, tide land reclamation projects were showed financially and economically feasible and environmentally sustainable. The joint cost like estuary dam should be allocated based on the multi-functional benefits of the projects. To allocate the joint cost, legal and institutional improvement should adapt the joint cost allocation method as the specific cost-remaining benefit method. Korea has more than 402,000 ha of tidal flat of which 76,396ha have been reclaimed in 2003. To meet food security and to cope with shortage of land, phil-environmental reclamation projects should be continuously implemented and necessary tidal flats for protecting environmental ecosystem should be remained according to the detail survey results of reclaimable resources.

  • PDF

2단계 필터링 기반 적조 탐지 알고리즘에 관한 연구 - MODIS 클로로필 정보에 적용 - (A Study on Red Tide Detection Algorithm Based on Two Stage filtering - Application to MODIS Chlorophyll Information -)

  • 김용민;김형태
    • 대한원격탐사학회지
    • /
    • 제24권4호
    • /
    • pp.325-331
    • /
    • 2008
  • 본 연구는 MODIS에서 제공하는 클로로필 정보를 기반으로 하여 2단계 필터링을 통해 우리나라 동해, 남해 연안에 대규모로 발생했던 Cochlodinium polykrikoides 적조를 탐지하는 알고리즘을 제시한다. 일반적으로 적조 탐지 연구들은 클로로필과 적조 발생의 상관성을 이용하여 클로로필의 농도가 높은 해역을 적조 발생 해역으로 탐지한다. 하지만 이 방법의 문제점은 적조가 발생하지 않은 해역을 적조 발생 해역으로 탐지함으로써 포함오차(Commission error)를 발생시킨다는 것이다. 따라서 본 연구에서는 이러한 문제점을 극복하기 위해 MODIS에서 제공하는 클로로필 정보를 바탕으로 적조 발생 해역을 추출하고, 2단계 필터 링 과정을 적용함으로써 진해, 여수, 남해도 부근 해역에서 발생한 포함오차를 제거하였으며, 그 결과를 국립수산과학원의 적조속보자료와 함께 시각적 정량적으로 평가하여 본 연구에서 제안한 알고리즘의 효용성을 검증하였다.

Satellite monitoring and prediction for the occurrence of the red tide in the coastal areas in the South Sea of Korea - I. The relationship between the occurrence of red tide and the meteorological factors

  • Yoon, Hong-Joo;Kim, Young-Seup;Kim, Sang-Woo
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
    • /
    • pp.656-656
    • /
    • 2002
  • It is studied on the relationship between the occurrence of red tide(Chlorophyll-a concentration by the in-situ and satellite data) and the meteorological factors (precipitation, air temperature, sunshine and winds) in the coastal areas in the South Sea of Korea. In summer and early-fall which frequently occurred the red tide, the precipitation above 213mm had directly influence on the occurrence of red tide because it carried the nutritive substance which originated from the land into the coastal areas. Then air temperature kept up generally high values as 23~26$^{\circ}C$, and sunshine with 187~198hours and wind velocity with 3.1~7.9m/s showed not directly the relationship on the occurrence of red tide.

  • PDF

확산모형에 의한 하구에서의 오염물질이동 예측(수공) (Prediction of Pollutant Transport by Dispersion Model on Estuary)

  • 박영욱;박상현;천만복;이봉훈;권순국
    • 한국농공학회:학술대회논문집
    • /
    • 한국농공학회 2000년도 학술발표회 발표논문집
    • /
    • pp.371-377
    • /
    • 2000
  • Environmental impact on a land reclamation project, Hwaong tidal barrier was studied using the dispersion and advection model to predict the influence of polluted water discharged from freshwater reservior. The simulation results show that the distribution of concentration by influence of polluted water discharged during a tidal cycle appeared to be extinguished at atmost all points after two tidal cycle. Peak concentration near the sluice gate is found out to be higher during the spring tide than neap tide. Equi-concentration contour line appeared to distributed a longer according to line of sea dike in spring tide than neap tide. The reasons is because influence by currents of northwest direction is a stronger, compared to spring tide and neap tide in the flood tide.

  • PDF

서해 조석현상에 따른 국지기상 변화가 수도권 오존농도에 미치는 영향 (Impacts of Local Meteorology caused by Tidal Change in the West Sea on Ozone Distributions in the Seoul Metropolitan Area)

  • 김성민;김유근;안혜연;강윤희;정주희
    • 한국환경과학회지
    • /
    • 제28권3호
    • /
    • pp.341-356
    • /
    • 2019
  • In this study, the impacts of local meteorology caused by tidal changes in the West Sea on ozone distributions in the Seoul Metropolitan Area (SMA) were analyzed using a meteorological model (WRF) and an air quality (CMAQ) model. This study was carried out during the day (1200-1800 LST) between August 3 and 9, 2016. The total area of tidal flats along with the tidal changes was calculated to be approximately $912km^2$, based on data provided by the Environmental Geographic Information Service (EGIS) and the Ministry of Oceans and Fisheries (MOF). Modeling was carried out based on three experiments, and the land cover of the tidal flats for each experiment was designed using the coastal wetlands, water bodies (i.e., high tide), and the barren or sparsely vegetated areas (i.e., low tide). The land cover parameters of the coastal wetlands used in this study were improved in the herbaceous wetland of the WRF using updated albedo, roughness length, and soil heat capacity. The results showed that the land cover variation during high tide caused a decrease in temperature (maximum $4.5^{\circ}C$) and planetary boundary layer (PBL) height (maximum 1200 m), and an increase in humidity (maximum 25%) and wind speed (maximum $1.5ms^{-1}$). These meteorological changes increased the ozone concentration (about 5.0 ppb) in the coastal areas including the tidal flats. The increase in the ozone concentration during high tide may be caused by a weak diffusion to the upper layer due to a decrease in the PBL height. The changes in the meteorological variables and ozone concentration during low tide were lesser than those occurring during high tide. This study suggests that the meteorological variations caused by tidal changes have a meaningful effect on the ozone concentration in the SMA.

회귀모형에 의한 서해안 평균해면의 연시계열자료의 평가 (The Evaluation of the Annual Time Series Data for the Mean Sea Level of the West Coast by Regression Model)

  • 조기태;박영기;이장춘
    • 한국환경과학회지
    • /
    • 제9권1호
    • /
    • pp.19-25
    • /
    • 2000
  • As the tideland reclamation is done on a large scale these days, construction work is active in the coastal areas. Facilities in the coastal areas must be built with the tide characteristics taken into consideration. Thus the tide characteristics affect the overall reclamation plan. The analysis of the tide data boils down to a harmonic analysis of the hourly changes of long-term tide data and extraction of unharmonic coefficients from the results. Since considerable amount of tide data of the West Coast are available, the existing data can be collected and can be used to obtain the temporal changes of the tide by being fitted into the tide prediction model. The goal of this thesis lies in assessing whether the mean sea level used in the field agrees with the analysis results from the long-term observation data obtained with their homogeneity guaranteed. To achieve this goal, the research was conducted as follows. First the present conditions of the observation stations, the land level standard, and the sea level standard were analyzed to set up a time series model formula for representing them. To secure the homogeneity of the time series, each component was separated. Lastly the mean sea level used in the field was assessed based on the results obtained form the analysis of the time series.

  • PDF

원격탐사를 이용한 한국 남해 중부해역에서의 적조 예찰 연구1. 적조발생과 기상인자간의 상관성 연구 (Study on monitoring and prediction for the occurrence of red tide in the middle coastal area in the South Sea of Korea 1. The relationship between the occurrence of red tide and the meteorological factors)

  • 윤흥주;김영섭;윤양호;김상우
    • 한국정보통신학회논문지
    • /
    • 제6권6호
    • /
    • pp.843-848
    • /
    • 2002
  • 남해 중부해역에서 적조발생과 관련해서 기상인자와의 상관성을 요약하면 다음과 같다. 적조 다발원 비교에서 강수량이 적조 발생과 밀접한 상관을 보였다. 즉, 강수량은 육지 및 연안지역의 영양염류를 해역으로 유입시킴으로서 적조발생의 영양 공급원으로 중요한 역할을 한다. 이때의 기온은 대체로 적조 다발철인 여름과 초가을에 높은 값을 유지했다. 그러나 일조시수나 바람은 적조발생에 직접적인 연관성을 가지지는 않은 것으로 사료된다.