• 한국수자원학회논문집
• /
• 제42권1호
• /
• pp.33-50
• /
• 2009

본 연구에서는 SLURP 장기 수문모형을 이용하여 미래기후와 예측된 토지이용자료 및 식생의 활력도를 고려한 상태에서 하천유역의 수문요소에 미치는 영향을 분석하였다. 경안천 상류유역($260.4\;km^2$)을 대상유역으로 선정하여 4개년(1999-2002) 동안의 일별 유출량 자료를 바탕으로 모형의 보정(1999-2000)과 검증(2001-2002)을 실시하였다. 모형의 보정 및 검정 결과 Nash-Sutcliffe 모형효율은 0.79에서 0.60의 범위로 $R^2$는 0.77에서 0.60의 범위로 나타났다. 미래 기후자료는 IPCC(Intergovernmental Panel on Climate Change)에서 제공하는 A2, A1B, B1 기후변화시나리오 의 MIROC3.2 hires, ECHAM5-OM 모델의 결과 값을 이용하였다. 먼저 과거 30년 기후자료(1977-2006, baseline)를 바탕으로 각 모델별 20C3M(20th Century Climate Coupled Model)의 모의 결과 값을 이용하여 강수와 온도를 보정 한 뒤 Change Factor Method로 downscaling 하였다. 미래 기후자료는 2020s(2010-2039), 2050s(2040-2069), 2080s(2070-2099)의 세 기간으로 나누어 분석하였다. 불확실성을 줄이고자 개선된 CA-Markov기법으로 미래 토지이용을 예측하였으며, 월별 NDVI와 월평균기온간의 선형 회귀식을 도출하여 미래의 식생지수 정보를 추정하였다. 모형의 적용결과, 미래 유출량은 MIROC3.2 hires는 A1B(2080s) 시나리오에서 연 유출량이 21.4% 증가, ECHAM5-OM은 A1B(2050s) 시나리오에서 8.9% 증가하였다. 증발산량은 MIROC3.2 hires가 3%, ECHAM5-OM은 16% 증가하였다. 미래 토양수분량은 현재에 비해 약 1% 정도 증가하였다.

• 한국수자원학회논문집
• /
• 제39권10호
• /
• pp.823-832
• /
• 2006

강우는 물과 에너지 순환에서 가장 중요한 역할을 한다. 이 연구에서는 두개의 다른 원격탐사 센서를 이용하여 추출한 강우자료의 불확실성 (uncertainty)에 대하여 검토해 보았으며, 이에 의한 오차가 비선형 수치수문모형에서 수문인자(유출)를 모의할 때 어떻게 영향을 미치는가를 살펴보았다. 지상에서 관측된 강우 관측을 이용하여 WSR-88D (NEXRAD)에 의해 추출한 레이더 강우, 그리고 IR (Infrared) 밴드를 기반으로 하는 인공위성 강우관측을 비교 검토하였으며, 세 가지의 서로 다른 강우와 현장에서 측정된 기상자료를 입력 자료로 사용하여, 오프라인 CLM (Community Land Model) 수문모형으로 유출량을 모의하였다. 이 연구에서 물리적 이론을 기반으로 하는 CLM수문 모형의 매개변수는 지표면-대기의 수문반응 (land-atmosphere interaction)을 적절하게 묘사하도록 정의되었다고 가정한다. 다른 원격탐사 센서를 이용하여 추출한 강우자료는 시공간적으로 다른 양상을 보여 주며, 수치모형의 실험 결과는 강우입력의 불확실성이 수문반응의 결과에 어떻게 영향을 미치는지를 보여준다. 이 연구는 앞으로 우리나라에서 개발 및 활용가능성이 있는 레이더 강우와 인공위성 강우에 대한 사전 지식을 제공하고, 동시에 수치 수문모형을 수행할 때 수문반응의 불확실성에 대한 정보를 제공해 주며, 결국은 기후 변화에 따른 수자원의 재분배를 이해하는데 이바지할 것이다.

• 한국산학기술학회논문지
• /
• 제22권4호
• /
• pp.545-553
• /
• 2021

기후변화와 도시화로 인해 도시 내 수재해의 발생 빈도가 지속적으로 증가하고 있다. 이로 인한 수재해 피해를 감소하기 위해, 대처방안에 대한 연구가 수행되고 있다. 도시유역의 정량적인 유출량 예측과 홍수량 저감 연구를 위해 유출량에 영향을 미치는 매개변수 중 하나인 침투성을 기준으로한 분석이 필요하다. 본 연구에서는 부산의 대표적 도시하천인 온천천 유역을 대상으로 SWAT 모형을 모의하여 수문학적반응단위별로 CN 값을 산정하여 침투성 맵을 작성하였다. 작성한 침투성 맵을 바탕으로 EPA SWMM을 이용해 단기 강우사상에 대해 LID 기술 적용이 유역의 물순환에 미치는 영향을 분석하였다. 대상유역에 적용된 LID 요소기술로는 주거단지지에 옥상녹화, 도로에 투수성포장을 설치하였다. 침투성 맵을 기준으로 선정된 소유역의 토지피복 상태와 LID 기술 적용에 따라 유출량, 첨두유량, 유출율은 감소하였고 침투량은 증가한 것으로 나타나 LID 기술이 도시유역의 물순환에 긍정적인 효과를 내는 것으로 확인하였다.

• 한국농공학회논문집
• /
• 제58권6호
• /
• pp.93-100
• /
• 2016

This study conducted a quantitative assessment on the environmental flows associated with climate change in the Gosam Reservoir, Korea. The application of RCP 8.5 climate change scenario has found that the peak value of High Flow Pulses has increased by 36.0 % on average compared to historical data (2001 ~ 2010), which is likely to cause disadvantage on flood control and management but the increase in peak value is expected to make a positive impact on resolving the issue of green algal blooms, promoting vegetation in surrounding areas and encouraging spawning and providing habitats for native species by releasing a larger amount of landslides as well as organic matters than the past. However, the decreasing pattern of the peak value of High Flow Pulses is quite apparent with the trend of delay on the occurrence time of peak value, necessitating a long-term impact analysis. The peak value of Large Floods shows a clear sign of decrease against climate change scenario, which is expected to lead to changes in fish species caused by degraded quality of water and decreasing habitats. A quicker occurrence of Small Floods is also expected to make an impact on the growth cycle of aquatic plants, and the reduction in occurrence frequency of Extreme Low Flows is to contribute to increasing the population of and raising the survival rate of native fish, greatly improving the aquatic ecosystem. The results of this study are expected to be useful to establish the water environment and ecological system in adapting or responding to climate change.

• 한국물환경학회지
• /
• 제24권6호
• /
• pp.806-816
• /
• 2008

In recent years, increases in impervious areas with rapid urbanization and land use changes are causing numerous hydrologic and environmental problems. In this study Low Impact Development (LID) was applied to investigate changes in runoff and peak runoff with LID plans. SWMM 5.0 was used to simulate LID Integrated Management Practices (IMPs) at study area. The SWMM estimated total runoff volume with conventional land use planning is (82.3%, 46.44 mm), (99%, 73.16 mm) greater than total runoff before urbanization, while total runoff with LID is (11.1%, 46.44 mm), (49%, 73.16 mm) greater than those before urbanization. With the LID adoption in land use planning, pervious area increases by 49.8% compared with that from the conventional urban land use planning, resulting in (32.7%, 46.44 mm), (23.6%, 73.16 mm) decrease in total runoff, and (32.6%, 46.44 mm), (18.5%, 73.16 mm) decreases in peak rate runoff. The results obtained from this study indicate that peak rate runoff, time to peak, and total runoff can be reduced with the LID in urban land use planning because the LID secures pervious areas with various LID IMPs. The SWMM simulated result using design storm data and the US EPA suggested CN values for various LID IMPs implies that how environment-friendly urban land use planning with the LID adoption is important for sustainable development at urbanizing watershed.

• 한국농공학회논문집
• /
• 제55권4호
• /
• pp.95-106
• /
• 2013

It is now generally known that dynamical climate modeling outputs include systematic biases in reproducing the properties of atmospheric variables such as, preciptation and temerature. There is thus, general consensus among the researchers about the need of bias-correction process prior to using climate model results especially for hydrologic applications. Among the number of bias-correction methods, distribution (e.g., cumulative distribution fuction, CDF) mapping based approach has been evaluated as one of the skillful techniques. This study investigates the uncertainty of using various CDF mapping-based methods for bias-correciton in assessing regional climate change Impacts. Two different dynamicailly-downscaled Global Circulation Model results (CCSM and GFDL under ARES4 A2 scenario) using Regional Spectial Model for retrospective peiod (1969-2000) and future period (2039-2069) were collected over the west central Florida. Total 12 possible methods (i.e., 3 for developing distribution by each of 4 for estimating biases in future projections) were examined and the variations among the results using different methods were evaluated in various ways. The results for daily temperature showed that while mean and standard deviation of Tmax and Tmin has relatively small variation among the bias-correction methods, monthly maximum values showed as significant variation (~2'C) as the mean differences between the retrospective simulations and future projections. The accuracy of raw preciptiation predictions was much worse than temerature and bias-corrected results appreared to be more significantly influenced by the methodologies. Furthermore the uncertainty of bias-correction was found to be relevant to the performance of climate model (i.e., CCSM results which showed relatively worse accuracy showed larger variation among the bias-correction methods). Concludingly bias-correction methodology is an important sourse of uncertainty among other processes that may be required for cliamte change impact assessment. This study underscores the need to carefully select a bias-correction method and that the approach for any given analysis should depend on the research question being asked.

• 한국물환경학회지
• /
• 제34권4호
• /
• pp.382-390
• /
• 2018

In this study, the LIDMOD3 was developed to design and evaluate low impact development (LIDMOD). In the same fashion, the LIDMOD3 employs a curve number (NRCS-CN) method to estimate the surface runoff, infiltration and event mean concentration as applicable to pollutant loads which are based on a daily time step. In these terms, the LIDMOD3 can consider a hydrologic soil group for each land use type LID-BMP, and the applied removal efficiency of the surface runoff and pollutant loads by virtue of the stored capacity, which was calculated by analyzing the recorded water balance. As a result of Model development, the LIDMOD3 is based on an Excel spread sheet and consists of 8 sheets of information data, including: General information, Annual precipitation, Land use, Drainage area, LID-BMPs, Cals-cap, Parameters, and the Results. In addition, the LIDMOD3 can estimate the annual hydrology and annual pollutant loads including surface runoff and infiltration, the LID efficiency of the estimated surface runoff for a design rainfall event, and an analysis of the peak flow and time to peak using a unit hydrolograph for pre-development, post-development without LID, and as calculated with LID. As a result of the model application as applied to an apartment, the LIDMOD3 can estimate LID-BMPs considering a well spatical distributed hydroloic soil group as realized on land use and with the LID-BMPs. Essentially, the LIDMOD3 is a screen level and simple model which is easy to use because it is an Excel based model, as are most parameters in the database. This system can be expected to be widely used at the LID site to collect data within various programmable model parameters for the processing of a detail LID model simulation.

• 대한원격탐사학회지
• /
• 제24권1호
• /
• pp.45-55
• /
• 2008

The impact on streamflow and groundwater recharge considering future potential climate and land use change was assessed using SLURP (Semi-distributed Land-Use Runoff Process) continuous hydrologic model. The model was calibrated and verified using 4 years (1999-2002) daily observed streamflow data for a $260.4km^2$ which has been continuously urbanized during the past couple of decades. The model was calibrated and validated with the coefficient of determination and Nash-Sutcliffe efficiency ranging from 0.8 to 0.7 and 0.7 to 0.5, respectively. The CCCma CGCM2 data by two SRES (Special Report on Emissions Scenarios) climate change scenarios (A2 and B2) of the IPCC (Intergovemmental Panel on Climate Change) were adopted and the future weather data was downscaled by Delta Change Method using 30 years (1977 - 2006, baseline period) weather data. The future land uses were predicted by CA (Cellular Automata)-Markov technique using the time series land use data of Landsat images. The future land uses showed that the forest and paddy area decreased 10.8 % and 6.2 % respectively while the urban area increased 14.2 %. For the future vegetation cover information, a linear regression between monthly NDVI (Normalized Difference Vegetation Index) from NOAA/AVHRR images and monthly mean temperature using five years (1998 - 2002) data was derived for each land use class. The future highest NDVI value was 0.61 while the current highest NDVI value was 0.52. The model results showed that the future predicted runoff ratio ranged from 46 % to 48 % while the present runoff ratio was 59 %. On the other hand, the impact on runoff ratio by land use change showed about 3 % increase comparing with the present land use condition. The streamflow and groundwater recharge was big decrease in the future.

• Proceedings of the National Institute of Ecology of the Republic of Korea
• /
• 제2권4호
• /
• pp.235-246
• /
• 2021

This study investigated the impact of baseflow on fish community in the Ungcheon stream (16.5 km long) located downstream of the Boryeong Dam, Korea. Based on field monitoring, there were five dominant fish species in the Ungcheon Stream accounting for 75% of the total fish community: Zacco platypus, Zacco koreanus, Tridentiger brevispinis, Rhinogobius brunneus, and Pungtungia herzi. These five fish species were selected as target species. HydroGeoSphere (HGS) and River2D models were used for hydrologic and hydraulic simulations, respectively. A habitat suitability index model was used to simulate fish habitat. To assess the impact of baseflow, each representative discharge was examined with or without baseflow. The HGS model was used to calculate baseflow within the study reach. This baseflow was observed to increase gradually with longitudinal distance. Validation of the hydraulic model dem onstrated that computed water surface elevated when baseflow was included, which was in good agreement with measured data, as opposed to the result when baseflow was excluded. Composite suitability index distributions and weighted usable area in the study reach were presented for target species. Simulations indicated that the baseflow significantly increased habitat suitability for the entire fish community. These results demonstrate that there should be a substantial focus on the baseflow for physical habitat simulation.

• 한국지리정보학회지
• /
• 제17권3호
• /
• pp.160-174
• /
• 2014

본 연구의 목적은 광역의 일단위 수문순환을 모의할 수 있는 격자기반의 분포형 모델을 구축한 후, 이를 미래 기후변화에 따른 광역적 수문영향을 평가하는데 있다. 격자별로 지표 유출층, 지표하 불포화 및 포화 토양층의 3단으로 구성하여 일별 물수지를 계산하며, 증발산량은 Penman-Monteith방법을 사용하였고, 지표 및 지표하유출은 지체계수(lag coefficient)와 감수곡선 계수(recession curve slope)를 적용하였다. 모델의 검보정을 위하여 한강유역의 충주댐과 소양강댐을 대상으로 9개년(2001-2009)의 댐유입량 자료를 이용하여 모델의 6개 주요매개변수를 보정하였으며, Nash-Sutcliffe 모델효율 (NSE)은 각각 0.57, 0.71의 값을 보였으며, 결정계수($R^2$)는 각각 0.65, 0.72의 값을 보였다. 5개의 IPCC SRES A1B 기후변화 시나리오자료(CSIRO MK3, GFDL CM2_1, CONS ECHO-G, MRI CGCM2_3_2, UKMO HADGEMI)를 적용한 결과, 미래 유출량의 변화는 강수량과 비슷한 경향을 보이면서 전체적으로 7.0%~27.1% 증가하였고, 증발산량도 미래 기온의 증가경향으로 일부 경우를 제외하고 증가하는 경향을 나타내었으며, 이들의 공간적 변화를 제시하였다.