• Title/Summary/Keyword: river basins

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Extraction of Snow Cover Area and Depth Using MODIS Image for 5 River Basins South Korea (MODIS 위성영상을 이용한 국내 5대강 유역 적설분포 및 적설심 추출)

  • Hong, U-Yong;Sin, Hyeong-Jin;Kim, Seong-Jun
    • KCID journal
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    • v.14 no.2
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    • pp.225-235
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    • 2007
  • The shape of streamflow hydrograph during the early period of spring is very much controlled by the area and depth of snow cover especially in mountainous area. When we simulate the streamfolw of a watershed snowmelt, we need some information for snow cover extent and depth distribution as parameters and input data in the hydrological models. The purpose of this study is to suggest an extraction method of snow cover area and snow depth distribution using Terra MODIS image. Snow cover extent for South Korea was extracted for the period of December 2000 and April 2006. For the snow cover area, the snow depth was interpolated using the snow depth data from 69 meteorological observation stations. With these data, it is necessary to run a hydrological model considering the snow-related data and compare the simulated streamflow with the observed data and check the applicability for the snowmelt simulation.

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Why the Mediterranean Sea Is Becoming Saltier

  • Bryden, Harry-L.;Boscolo, Roberta
    • Journal of the korean society of oceanography
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    • v.37 no.3
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    • pp.117-124
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    • 2002
  • Anthropogenic changes have been made to the water budget for the Mediterranean Sea as a result of river diversion projects. The decrease in freshwater inflow to the Mediterranean represents an effective increase in the overall net evaporation over the basin. Hydraulic control models for the exchange between the Mediterranean and Atlantic through the Strait of Gibraltar predict that the salinity of the Mediterranean should increase if the net evaporation over the Mediterranean increases. Increases in the salinity of the deep waters in both the western and eastern Mediterranean basins have been observed. The causes of such higher deep water salinity are attributed to increases in intermediate water salinity which are ultimately mixed down into the deep sea during wintertime buoyancy loss events. The pattern of the Mediterranean salinity increase is instructive for understanding how the water mass properties in a basin change over time as a result of anthropogenic changes.

Development of Integrated Water Quality Management Model for Rural Basins using Decision Support System. (의사결정지원기법을 이용한 농촌유역 통합 수질관리모형의 개발)

  • 양영민
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.5
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    • pp.103-113
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    • 2000
  • A decision support system DSS-WQMRA (Decision Support System-Water Quality Management in Rural Area) was developed to help regional planners for the water quality management in a rural basin. The integrated model DSS-WQMRA, written in JAVA, includes four subsystems such as a GIS, a database, water quality simulation models and a decision model. In the system, the GIS deals with landuse and the location of pollutant sources. The database manages each data and supplies input data for various water quality simulation models. the water quality simulation model is composed of the GWLF( Generalized Watershed Loading Function), PCLM(Pollutant Loading Calculation Module) and the WASP5 model. The decision model based on mixed integer programming is designed to determine optimal costs and thus allow the selection of managemental practices to meet the water quality criteria. The methodology was tested with an example application in the Bokha River Basin, Kyunggi Province in Korea. It was proved that the integrated model DSS-WQMRA could be very useful for water quality management including the non-point source pollution in rural areas.

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Flood Frequency Analysis at Indogyo Station in Han River Basins (한강 인도교지점에서의 홍수빈도해석에 대한 고찰)

  • Lee, Young Seok;Kim, Kyung Duk;Heo, Jun-Haeng
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.1098-1102
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    • 2004
  • 본 연구에서는 수도권을 포함하는 한강하류부에서 가장 중요한 측수지점중 하나인 인도교지점의 연 최대 홍수량 자료에 내해서 빈도해석을 시행하였다. 자료를 3개의 자료(자료 I : $1918\~1940$, 자료 II: $1952\~2002$, 자료 III: 결측치를 제외한 $1918\~2002$)로 구분하였으며, 수문자료에 일반적으로 많이 사용하는 13가지 확률 분포형을 적용하여 매개변수를 추정한 뒤 적합성여부를 판정하였으며, 적합도 검정방법 및 도시적인 방법을 통하여 적정 확률분포형을 선정하였고, 채택된 분포형(gamma-3, GEV, Gumbel, Weibull-2)에 내하여 확률홍수량을 산정하였다. 또한, 위치도시공식(plotting position formula)과 역사적 홍수정보(historic information)를 이용한 빈도해석 결과와도 비교${\cdot}$분석하였다. 그 결과 확률분포형 가운데에는 GEV와 Gumbel 분포형이 인도교지점의 홍수빈도해석에 적합한 것으로 판단된다.

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Extraction of Snowmelt Parameters using NOAA AVHRR and GIS Technique for 5 River Basins in South Korea (NOAA AVHRR 영상 및 GIS 기법을 이용한 국내 5대강 유역의 융설 매개변수 추출)

  • Shin, Hyung-Jin;Park, Geun-Ae;Kim, Seong-Joon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.194-198
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    • 2007
  • 융설 모형의 중요 매개변수인 적설분포면적은 실제 우리나라에서 적설과 관련한 관측 자료의 부족으로 인해 매개변수 추정이 어렵다. 이러한 문제점 해결을 위해 원격탐사기법을 활용하여 적설분포면적을 추출하였다. 본 연구에서는 1997년부터 2006년까지의 겨울철 NOAA (National Oceanic and Atmospheric Administration)의 AVHRR(Advanced Very High Resolution Radiometer) 위성영상의 8 sets의 총 108개 영상을 이용하여 적설분포면적을 추출하였고, 기상청의 지상기상관측소의 최심적설심 자료를 이용하여 GIS 자료를 구축함으로써 적설심의 공간적 분포를 추출하였다. 이를 국내 5대유역인 한강, 낙동강, 금강, 영산강, 섬진강 유역에 대하여 융설모형의 주요 매개변수인 적설분포면적, 유역 평균, 최대 적설심과 적설분포감소비곡선을 구축하였다. 그 중 적설분포면적감소곡선 (SDC : Snow cover Depletion Curve)는 적설분포면적의 감소형태를 나타내주는 지표로써 융설의 가장 민감한 매개변수이다. 이를 국내 5대강 유역에 대해 구축하여 정량화하였다.

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A Comparative Study of Linear-Nonlinear Flood Runoff Models. (선형-비선형 홍수유출모델의 비교연구)

  • 이순택;이영화
    • Water for future
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    • v.19 no.3
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    • pp.267-276
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    • 1986
  • This study aims at the development of flood runoff model by comparing and analyzing nonlinear models with linear models in rier basins. The models which are used at the analysis are Nash model and Runoff function method as linear models, and Tank model and Storage function method as nonlinear models. The results, which are obtained from the analysis of these models by using hydrologic data of a representative basin in Nakdong river, Wi-chun basin, show that the peak time, peak flow and flood hydrogrphs by nonlinear models are better than those by linear models in comparison with observed ones, and that nonlinear models are suittable as flood runoff model.

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A Basic Study on the Flood-Flow Forecasting System Model with Integrated Optimal Operation of Multipurpose Dams (댐저수지군의 최적연계운영을 고려한 유출예측시스템모형 구축을 위한 기초적 연구)

  • 안승섭
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.37 no.3_4
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    • pp.48-60
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    • 1995
  • A flood - flow forecasting system model of river basins has been developed in this study. The system model consists of the data management system(the observation and telemetering system, the rainfall forecasting and data-bank system), the flood runoff simulation system, the reservoir operation simulation system, the flood forecasting simulation system, the flood warning system and the user's menu system. The Multivariate Rainfall Forecasting model, Meteorological factor regression model and Zone expected rainfall model for rainfall forecasting and the Streamflow synthesis and reservoir regulation(SSARR) model for flood runoff simulation have been adopted for the development of a new system model for flood - flow forecasting. These models are calibrated to determine the optimal parameters on the basis of observed rainfall, 7 streamfiow and other hydrological data during the past flood periods.

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Areal Distribution of Runoff Volume by Seasonal Watershed Model (계절유역 모형을 사용한 유량의 공간적분포 결정)

  • 선우중
    • Water for future
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    • v.17 no.2
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    • pp.125-131
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    • 1984
  • watershed Model by mathematical formulation is one of the powerful tool to analyze the hydrologic process in a watershed. The seasonal watershed model is one of the mathematial model from which the monthly streamflow can be simulated and forcasted for given precipitaion data. This model also enables us to compute the monthly runoff at each subbgasin when the basin is subdivided into several small subbasins. The computation of runoff volume makes a Prediction of the areal distirbution of runoff volume for a given precipitation data. Several basins in Han River basin were chosen to simulate the monthly runoff and compute the runoff at each subbasin. A simple logarithmic regression were conducted between runoff ratio and area ratio. The correlation was very high and the equation can be used for prediciting flood volume when flood at downstream gaging station is know.

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Hypersensitive Reaction to Praziquantel in a Clonorchiasis Patient

  • Lee, Jung-Min;Lim, Hyun-Sul;Hong, Sung-Tae
    • Parasites, Hosts and Diseases
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    • v.49 no.3
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    • pp.273-275
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    • 2011
  • Praziquantel is the drug of choice for clonorchiasis. Since clonorchiasis is endemic in most river basins, praziquantel has been widely used for 30 years in Korea. A 54-year-old Korean woman suffered from hypersensitive reactions, such as nausea, dyspnea, rash, and urticaria after taking the first dose of praziquantel to treat clonorchiasis. She ingested one dose again and the same symptoms appeared, and she was treated at a clinic with anti-histamines. She tried one more dose with anti-histamines but found the same symptoms. Later, she was found to pass eggs of Clonorchis sinensis and medicated with flubendazole. The hypersensitive reaction to praziquantel is rare but occurs. This is the 5th case report in the world.

Sensitivity of Flow Metrics to Climate Variability and Extremes in Korea

  • Kim, Jong-Suk;Jain, Shaleen;Yuk, Ji Moon;Moon, Young-Il
    • Proceedings of the Korea Water Resources Association Conference
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    • 2016.05a
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    • pp.117-117
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    • 2016
  • The natural hydrologic regime is intimately tied to the structure and function of stream and riparian ecosystems. Consequently, understanding the nature and extent of perturbations to the hydrologic regime, stemming from episodic-to-seasonal and longer-term climatic variations, as well as anthropogenic influences is an important starting point for developing an improved understanding of the coupled human-environmental systems. Herein, we pursued to explicate sensitivity of ecologically relevant flow metrics to climate variability and extremes in the five major river basins, Korea.

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