• Journal of Korea Water Resources Association
• /
• v.52 no.6
• /
• pp.381-395
• /
• 2019

The purpose of this study is to predict agricultural reservoir storage rate (RSR) in a month. This algorithm was developed by multiple linear regression model (MLRM) which included the past 3 months RSRs data and the future climate change scenarios. In order to improve use of predicted RSR, this study need the severe criteria in terms of drought. So, the predicted RSR was indexed as the 3 months reservoir drought index (RDI3) and then it was disaggregated into drought duration, severity, and intensity. For the future RSR estimation by climate change scenarios, the 6 RCP 8.5 scenarios of HadGEM2-ES, CESM1-BGC, MPI-ESM-MR, INM-CM4, FGOALS-s2, and HadGEM3-RA were used in three future evaluation periods (S1: 2011~2040, S2: 2041~2070, S3: 2071~2099). The future S3 period of HadGEM2-ES scenario which has the biggest increase in precipitation and temperature showed the largest decrease to 60.2% among the 6 scenarios compared to the historical RSR (1976~2005) 77.3%. In contrast, INM-CM4 scenario which has smallest changes in precipitation and temperature in S3 period showed the smallest decrease to 72.8%. For the CESM1-BGC and MPI-ESM-MR, FGOALS-s2, and HadGEM3-RA, the S3 period RSR showed 72.6%, 72.6%, 67.4%, and 64.5% decrease respectively. The future severe drought condition of RDI3 below -0.25 showed the increase trend for the number and severity up to -2.0 during S3 period.

• Journal of the Korean association of regional geographers
• /
• v.19 no.4
• /
• pp.615-626
• /
• 2013

In this study, spatial patterns of the urban flood vulnerability index in Seoul are examined by considering climate exposure, sensitivity, and adaptability associated with floodings for recent 5 year (2006~2010) period by the smallest administrative unit called Dong. According to the results of correlation analyses based on the IPCC(Intergovernmental Panel on Climate Change)'s vulnerability model, among many variables associated with urban flooding, rainwater tank capacity, 1-day maximum precipitation and flood pumping station capacity have statistically-significant, and relatively-high correlations with the number of flood damage in Seoul. The flood vulnerability map demonstrates that the extensive areas along Anyang and Joongnang streams show relatively high flood vulnerability in Seoul due to high sensitivity. Especially in case of Joongnang stream areas, climatic factors also contribute to the increase of flood vulnerability. At local scales, several Dong areas in Gangdong-gu and Songpa-gu also show high flood vulnerability due to low adaptability, while those in Gangnam-gu do due to high sensibility and climate factor such as extreme rainfall events. These results derived from the flood vulnerability map by Dong unit can be utilized as primary data in establishing the adaptation, management and proactive policies for flooding prevention within the urban areas in more detail.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2018.05a
• /
• pp.311-311
• /
• 2018

Generally, the water resources in South Korea were supplied from river flow and dam. Among them, the dam is the most important supplier for the residential and industrial water. However, the climate change has caused a setback in water supply chain. The objective of the study is therefore to suggest a drought index consideing dam water shortage for efficiently dam and water resources management. The standardzied balanced index(SBI), which has same concept with the standardzied precipitation index, were suggested. Also, the management index for the dam were established with SSVI and the storage percentage that compared to previous years.

• Journal of Korea Water Resources Association
• /
• v.45 no.4
• /
• pp.393-407
• /
• 2012

This study suggests the results of temporal and spatial variations for rainfall data in the Korean Peninsula. We got the index of the rainfall amount, frequency and extreme indices from 65 weather stations. The results could be easily understood by drawing the graph, and the Mann-Kendall trend analysis was also used to determine the tendency (up & downward/no trend) of rainfall and temperature where the trend could not be clear. Moreover, by using the FARD, frequency probability rainfalls could be calculated for 100 and 200 years and then compared each other value through the moment method, maximum likelihood method and probability weighted moments. The Average Rainfall Index (ARI) which is meant comprehensive rainfalls risk for the flood could be obtained from calculating an arithmetic mean of the RI for Amount (RIA), RI for Extreme (RIE), and RI for Frequency (RIF) and as well as the characteristics of rainfalls have been mainly classified into Amount, Extremes, and Frequency. As a result, these each Average Rainfall Indices could be increased respectively into 22.3%, 26.2%, and 5.1% for a recent decade. Since this study showed the recent climate change trend in detail, it will be useful data for the research of climate change adaptation.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2017.05a
• /
• pp.210-210
• /
• 2017

기후변화로 인한 이상기후 현상으로 이상홍수, 극한홍수의 발생빈도가 증가하고 있으며, 그 피해 양상 또한 대형화 다양화되고 있다. 최근 2014년 일본의 태풍 '판폰'과 '봄퐁', 2013년 중국의 태풍 '피토', '다나스', 2012년 한국의 태풍 '볼라벤', '덴빈', '산바'가 연속적으로 발생하는 등 연속적인 강우 사상으로 인한 피해가 발생하고 있다(최창현 등, 2016). 연속적인 강우사상으로 인한 홍수량은 단일 강우사상으로 발생하는 홍수량에 비해 6~17% 정도 증가된다(최창현 등, 2016). 단일강우 사상으로 인한 일반 홍수량에 비해 그 뒤에 따라오는 연속적인 강우로 인한 홍수량 증가에 따른 피해는 막대한 인명과 재산피해가 발생할 것으로 추정된다. 이에 연속적인 강우사상으로 인한 피해를 대비하기 위한 구조물적 비구조물적 홍수방어 대책 수립이 시급한 실정이다. 연속적인 강우사상으로 인한 홍수방어 대책을 수립하기 위해서는 먼저 연속적인 강우사상으로 인한 정확한 홍수량 모의가 필요하다. 하지만 국내 외에서는 단일강우사상에 대한 홍수량 산정 연구는 활발히 진행되어 왔지만, 연속강우사상에 대한 홍수량 산정 연구는 미비한 상태이다. 따라서, 본 연구에서는 다양한 홍수량 산정 방법을 이용하여 연속적인 강우사상에 대한 홍수량을 산정하고, 이를 비교 분석하여 연속적인 강우사상에 가장 적합한 홍수량 산정 방법을 제시하고자 한다. 본 연구결과를 통해 연속적인 강우사상을 고려한 홍수방어 대책 수립 시 기초자료로 활용할 수 있을 것으로 판단된다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2008.05a
• /
• pp.1235-1239
• /
• 2008

최근 기상이변 및 이상기후로 인해 예상치 못한 극치사상이 빈번하게 발생하고 있으며, 이로 인한 수자원관리 측면에 있어 많은 어려움을 겪고 있다. 특히 집중호우나 태풍 사상과 같이 단 시간 내에 많은 양의 강수량을 동반한 경우 댐과 같은 대형 수공구조물의 파괴로 인해 인명 및 재산피해의 가능성을 증가시키고 있다. 따라서 본 연구에서는 우리나라에 발생하는 시간강수량에 대한 평가를 하기 위해 우리나라에 발생하는 시간강수량과 수문기상인자인 해수면 온도 및 습윤지수와의 상관관계 분석을 통해 수문기상인자가 우리나라 강수량에 미치는 영향을 평가하였다. 또한, 우리나라에 발생하는 극한강우를 발생 원인별로 태풍 사상과 집중호우 사상으로 구분하여 수문기상인자와의 상관성 분석 결과를 바탕으로 Empirical Simulation Technique 기법을 적용하여 집중호우와 태풍으로 발생하는 강우의 특성을 평가하였다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2015.05a
• /
• pp.613-613
• /
• 2015

최근 전 지구적인 온난화로 인한 이상기후에 따라 강수량이 증가하고, 특정지역에만 국한되어 집중적으로 비가 내리는 국지성 집중호우의 발생 빈도가 증가하여 이로 인한 극한 홍수나 강우로 인한 산사태 등의 재해가 반복적으로 발생하고 있다. 홍수는 재산 및 인명에 이르기까지 막대한 피해를 야기한다는 점에서 이를 대비하기 위한 방안이 필수적이므로 국가적인 차원에서 홍수피해를 경감시키기 위한 여러 가지 구조적 또는 비구조적 대책들을 제시하고 있지만, 정확한 기상 변화의 예측이 어렵고 다양한 유발 원인들로부터 비롯된 홍수에 모두 대응할 수 있는 통합 대책 마련이 어려운 실정이다. 즉, 사전예방보다는 피해 복구에만 중점을 두고 있기 때문에 홍수 발생 유역의 지역적인 홍수피해 특성을 반영하지 못할 뿐만 아니라 어느 지역이 상대적으로 홍수피해의 위험성이 높은 지역인지도 파악하기 어렵다. 따라서, 본 연구에서는 도시홍수피해 유형인 내수침수피해와 외수침수피해의 유형에 따라 사례들을 조사하고 관련문헌들로부터 도시 홍수 취약성 평가를 위한 대표적 인자들을 도출하였다. 도출된 인자들을 각각 IPCC의 취약성 평가 프레임에 따라 기후노출, 민감도 그리고 적응능력으로 구분하고 도시 상습침수지역인 도림천 유역을 시범 지역으로 하여 도시홍수 취약성 평가를 위한 지수를 개발하고자 한다. 본 연구를 통하여 향후 도시홍수피해의 잠재적 위험성이 높을 것으로 판단되는 유역에 대한 활용방안을 제시하고 유역의 특성 및 중요도에 따른 치수사업의 우선순위를 결정하는 등 유역의 특성을 반영한 구체적 적응정책의 방향성을 세우는데 기초자료로 제공될 수 있으며, 도시홍수로 인한 인명 및 재산의 피해를 최소화 하는 것에 목적이 있다.

• Journal of Wetlands Research
• /
• v.15 no.4
• /
• pp.595-607
• /
• 2013

In this study we estimated ETCCDI and frequency based precipitation using observed precipitation and precipitation from Representative Concentration Pathway(RCP) scenarios for 58 weather stations which have the recorded data more than 30 years. We tried to eliminate the bias by Quantile Mapping and tested for outliers of simulated data under climate change scenario. Then we estimated ETCCDI related to precipitation and frequency based precipitation for the future. In addition to this study examined the changes of frequency based precipitation for the future target periods. According to the result, dry days will be increased in Korean Peninsula in the 2090s. Also it showed that the number of heavy precipitation day more than 80mm/day tends to be increased in 3~7% in the future. The precipitation of 24-hour duration under climate change will be increased by 17.7% for 80-year frequency, 18.2% for 100-year frequency and 19.6% for 200-year frequency in 2090s. In the 21st century, the damage caused by natural disasters is expected to be increased due to increase of precipitation and the change of runoff characteristics under climate change. Therefore, the proposed ETCCDI and precipitation frequency under climate change are expected to be used for the future natural disaster plan.

• Journal of Korea Water Resources Association
• /
• v.51 no.12
• /
• pp.1195-1205
• /
• 2018

In the study, the water shortage of Boryeong Dam watershed ($163.6km^2$) was evaluated under future climate change scenario. The Soil and Water Assessment Tool (SWAT) was used considering future dam release derived from multiple linear regression (MLR) analysis. The SWAT was calibrated and verified by using daily observed dam inflow and storage for 12 years (2005 to 2016) with average Nash-Sutcliffe efficiency of 0.59 and 0.91 respectively. The monthly dam release by 12 years MLR showed coefficient of determination ($R^2$) of above 0.57. Among the 27 RCP 4.5 scenarios and 26 RCP 8.5 scenarios of GCM (General Circulation Model), the RCP 8.5 BCC-CSM1-1-M scenario was selected as future extreme drought scenario by analyzing SPI severity, duration, and the longest dry period. The scenario showed -23.6% change of yearly dam storage, and big changes of -34.0% and -24.1% for spring and winter dam storage during 2037~2047 period comparing with 2007~2016 period. Based on Runs theory of analyzing severity and magnitude, the future frequency of 5 to 10 years increased from 3 in 2007~2016 to 5 in 2037~2046 period. When considering the future shortened water shortage return period and the big decreases of winter and spring dam storage, a new dam operation rule from autumn is necessary for future possible water shortage condition.

• Journal of Korea Water Resources Association
• /
• v.53 no.6
• /
• pp.409-416
• /
• 2020

An extreme climate monitoring is essential to the reduction of socioeconomic damages from extreme events. The objective of this study was to produce the near-realtime weekly root-zone Soil Moisture Index (SMI) on the basis of soil moisture using the Noah 3.3 Land Surface Model (LSM) for potentially monitoring extreme drought events. The Yangtze basin was selected to evaluate the Noah LSM performance for the East Asia region (15-60°N, 70-150°E) and the evapotranspiration (ET) and sensible heat flux (SH) were compared with ET and SH from FluxNet and with ET from FluxCom, Global Land Evaporation Amsterdam Model (GLEAM), ERA-5, and Generalized Complementary Relationship (GCR). For the ET, the coefficients of determination (R²) were higher than 0.96, while the R² value for the SH was 0.71 with slightly lower than those. A time series of the weekly root-zone SMI revealed that the regions with Extreme drought had been expanded from the northern part of East China to the entire East China between July to October 2019. The trend analysis of the number of extreme drought events showed that extreme drought events in spring had reduced in South Korea over the past 20 years, while those in fall had a tendency to increase. It is concluded that this study can be useful to reduce the socioeconomic damages resulted from climate extremes by comprehensively characterizing extreme drought events.