• Journal of Environmental Science International
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• v.29 no.9
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• pp.871-883
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• 2020

Due to recent heavy rain events, there are increasing demands for adapting infrastructure design, including drainage facilities in urban basins. Therefore, a clear definition of urban rainfall must be provided; however, currently, such a definition is unavailable. In this study, urban rainfall is defined as a rainfall event that has the potential to cause water-related disasters such as floods and landslides in urban areas. Moreover, based on design rainfall, these disasters are defined as those that causes excess design flooding due to certain rainfall events. These heavy rain scenarios require that the design of various urban rainfall facilities consider design rainfall in the target years of their life cycle, for disaster prevention. The average frequency of heavy rain in each region, inland and coastal areas, was analyzed through a frequency analysis of the highest annual rainfall in the past year. The potential change in future rainfall intensity changes the service level of the infrastructure related to hand-to-hand construction; therefore, the target year and design rainfall considering the climate change premium were presented. Finally, the change in dimensional safety according to the RCP8.5 climate change scenario was predicted.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.1
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• pp.119-126
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• 2020

This study analyzed the effects of future climate change on water resources in the Gyeongan-cheon watershed of the Han River. Considering the uncertainties of GCM climate data, future data using 16 GCMs and SQM downscaling method are used. And SWAT model was applied to simulate the hydrological changes from the past to the future. The maximum to minimum difference according to GCM for the future period (2010-2099) was about 1,500 mm of annual precipitation, 150 mm of evapotranspiration, 1,380 mm of runoff, and the deviation from the mean was -40 % to +60 % of precipitation, ±15 % of evapotranspiration, -60 % to +90 % of runoff, which means that the variability is very high according to GCM. The impacts of climate change over the three future periods showed that precipitation, evapotranspiration, and runoff were expected to increase gradually toward the far future (2070-2099), and would be relatively larger under the RCP 8.5 scenario. On a monthly basis, it was analyzed that precipitation and runoff increased in July to September, while the evapotranspiration decreased in July and August, and increased in September and October. The results of this study are expected to be helpful in understanding the future climate impacts of various GCM data and the uncertainties associated with GCMs.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.326-326
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• 2017

Climate warming is the issue on the global scale. Soybean can be seriously damaged when high temperature occurs during a reproductive stage such as the flowering and pod-setting period according to the Representative Concentration Pathway (RCP) (2021~2100) 8.5 scenarios. The weather in 2016 was very different from other years (average for 30 years from 1980 to 2010) ; the highest temperature was $33.7^{\circ}C$ which was higher $3.29^{\circ}C$ than average temperature from last 30 years and average rainfall was 26.5 mm, lower 140.9 mm than average rainfalls from other years. Especially, the highest temperature during soybean flow-ering and pod setting stage was $26.8^{\circ}C$ which was higher $0.1^{\circ}C$ and rainfall was 172.2 mm, higher 47.8 mm than other years from the first to the 20th in the October at soybean seed elongation stage. Soybean leaves were turned upside down by the drought stress during the flowering and pod-setting stage. The numbe-r of pods and seeds per unit area decreased 11.0% and 30.3% compared with the previous year, respectively. The ripening period was prolonged by 21 days because of high temperature and soil moisture contents due to the continual rainmade increase of the seed weight up to 15.6% and the yield decreased 7.1% compared to the previous year.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.501-511
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• 2016

Predicting potential spatial distribution of Monochamus alternatus, a major insect vector of the pine wilt disease, is essential to the spread of the pine wilt disease. The purpose of this study was to predict future domestic spatial distribution of M. alternatus by using the CLIMEX model considering the temperature condition of the vector's life history. To predict current distribution of M. alternatus, the administrative divisions data where the pine wilt spots caused by M. alternatus were found from 2006 to 2014 and the 10-year mean climate observed data in 68 meteorological stations from 2006 to 2015 were used. Eight parameter sets were chosen based on growth temperature range of M. alternatus reported in preceding researches. Error matrix method was utilized to select and simulate the parameter sets showing the highest correlation with the actual distribution. Regarding the future distribution of M. alternatus, two periods of 2050s(2046-2055) and 2090s(2091-2100) were predicted using the projected climate data of RCP 8.5 Scenario generated from Korea Meteorological Administration. Overall results of M. alternatus distribution simulation were fit in the actual distribution; however, overestimation in Seoul Metropolitan area and Chungnam Region were shown. Gradual expansion of M. alternatus would be expected to nationwide from western and southern coastal areas of Korea peninsula.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.169-169
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• 2022

Over the past 100 years, the global average temperature has risen by 0.75 ℃. The Korean Peninsula has risen by 1.8 ℃, more than twice the global average. According to the RCP 8.5 scenario, the CO₂ concentration in 2100 will be 940 ppm, about twice as high as current. The National Institute of Crop Science(NICS) is using the SPAR (Soil-Plant Atmosphere Research) facility that can precisely control the environment, such as temperature, humidity, and CO₂. A Python-based colony photosynthesis algorithm has been developed, and the carbon and nitrogen absorption rate of rice is evaluated by setting climate change conditions. In this experiment, Oryza Sativa cv. Shindongjin were planted at the SPAR facility on June 10 and cultivated according to the standard cultivation method. The temperature and CO₂ settings are high temperature and high CO₂ (current temperature+4.7℃ temperature+4.7℃·CO₂ 800ppm), high temperature single condition (current temperature+4.7℃·CO₂ 400ppm) according to the RCP8.5 scenario, Current climate is set as (current temperature·CO₂400ppm). For colony photosynthesis measurement, a LI-820 CO₂ sensor was installed in each chamber for setting the CO₂ concentration and for measuring photosynthesis, respectively. The colony photosynthetic rate in the booting stage was greatest in a high temperature and CO₂ environment, and the higher the nitrogen fertilization level, the higher the colony photosynthetic rate tends to be. The amount of photosynthesis tended to decrease under high temperature. In the high temperature and high CO₂ environment, seed yields, the number of an ear, and 1000 seed weights tended to decrease compared to the current climate. The number of an ear also decreased under the high temperature. But yield tended to increase a little bit under the high temperature and high CO₂ condition than under the high temperature. In addition, In addition to this study, it seems necessary to comprehensively consider the relationship between colony photosynthetic ability, metabolite reaction, and rice yield according to climate change.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2016.11a
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• pp.205-206
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• 2016

최근 기후변화로 인하여 태풍 및 집중호우로 인한 극한 강우사상의 발생빈도가 증가하고 있다. 급격한 도시화로 인한 유역 내 불 투수 면적이 늘어나고, 도달시간이 짧아지면서 집중호우에 취약한 도시하천의 분포가 늘어나고 있다. 특히 도시하천은 공공시설물 및 인구밀집으로 인하여 집중호우로 인한 홍수 발생시 대규모 재산피해와 인명피해가 발생할 것으로 추정된다. 따라서 본 연구에서는 기후변화로 인한 집중호우 발생시 도시하천의 홍수피해액을 산정하고자 한다. 기후변화로 인한 집중호우는 RCP8.5시나리오의 강우자료를 적용하였으며, HEC-HMS와 HEC-RAS를 이용하여 홍수량을 산정하였다. 또한 피해액을 산정하기 위하여 다차원홍수피해액산정방법을 이용하여 도시하천의 피해액을 산정하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.562-562
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• 2015

하천의 유황특성을 분석하는 것은 하천생태계의 변화를 파악하고 예측하는데 있어 매우 중요하다고 할 수 있다. 최근에는 수문학적인 변화과정을 통계학적 기법을 적용하여 정량적인 지표로 산정하고 분석하는 모델을 개발하여 다양한 연구가 진행되고 있다. 특히 미국 Nature Conservancy에서 개발한 수문변화지표법(IHA)은 일(daily)유출량 자료로부터 수문학적 관점에서의 특성지표와 환경유량 관점에의 변화지표를 분석함으로써 하천 유황변동을 정량화 할 수 있다. 본 연구는 기후변화가 향후 하천유황과 수생태계에 미치는 영향을 분석하기 위해 중규모 하천유역인 만경강을 대상으로 하고 RCP 8.5 기후변화시나리오를 기반으로 준분포형 모형인 SLURP 모형으로부터 일(daily)단위의 유출모의 시나리오를 작성하였다. 그리고 수문변화지표법(IHA)을 이용하여 기후변화에 따른 하천 유황과 수생태계에 미치는 영향을 정량화하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.316-316
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• 2021

Erosion in a watershed is one of the main sources of sediment inflow in dams. While sediment management practices can be performed to reduce and manage sedimentation in reservoirs, managing the sediment inflow before it reaches the reservoir should also be consider. The accurate location of areas with high erosion and deposition rates should be determined in order to propose an appropriate sediment management procedure such as the construction of check dams. In this study, the projected rainfall from HadGEMRA-3 for RCP 8.5, was used in C-SEM, a distributed rainfall-erosion model, to determine the projected spatial erosion patterns in Cheoncheon catchment, which is located in the upstream part of Yongdam Dam.

• Ecology and Resilient Infrastructure
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• v.2 no.3
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• pp.198-205
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• 2015

Impacts of climate change on aquatic ecosystems range from changes in physiological processes of aquatic organisms to species distribution. In this study, MaxEnt that has high prediction power without nonoccurrence data was used to simulate fish distribution changes in the Geum river watershed according to climate change. The fish distribution in 2050 and 2100 was predicted with RCP 8.5 climate change scenario using fish occurrence data (a total of 47 species, including 17 endemic species) from 2007 to 2009 at 134 survey points and 9 environmental variables (monthly lowest, highest and average air temperature, monthly precipitation, monthly lowest, highest and average water temperature, altitude and slope). The fitness of MaxEnt modeling was successful with the area under the relative operating characteristic curve (AUC) of 0.798, and environmental variables that showed a high level of prediction were as follows: altitude, monthly average precipitation and monthly lowest water temperature. As climate change proceeds until 2100, the probability of occurrence for Odontobutis interrupta and Acheilognathus yamatsuatea (endemic species) decreases whereas the probability of occurrence for Microphysogobio yaluensis and Lepomis macrochirus (exotic species) increases. In particular, five fish species (Gnathopogon strigatus, Misgurnus mizolepis, Erythroculter erythropterus, A. yamatsuatea and A. koreensis) were expected to become extinct in the Geum river watershed in 2100. In addition, the species rich area was expected to move to the northern part of the Geum river watershed. These findings suggest that water temperature increase caused by climate change may disturb the aquatic ecosystem of Geum river watershed significantly.

• Economic and Environmental Geology
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• v.54 no.2
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• pp.161-176
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• 2021

In this study, one of the distributed hydrologic models, VELAS, was used to analyze the variation of hydrologic elements based on water balance analysis to evaluate the groundwater recharge in more detail than the annual time scale for the past and future. The study area is located in Yanggok-ri, Seobu-myeon, Hongseong-gun, Chungnam-do, which is very vulnerable to drought. To implement the VELAS model, spatial characteristic data such as digital elevation model (DEM), vegetation, and slope were established, and GIS data were constructed through spatial interpolation on the daily air temperature, precipitation, average wind speed, and relative humidity of the Korea Meteorological Stations. The results of the analysis showed that annual precipitation was 799.1-1750.8 mm, average 1210.7 mm, groundwater recharge of 28.8-492.9 mm, and average 196.9 mm over the past 18 years from 2001 to 2018 in the study area. Annual groundwater recharge rate compared to annual precipitation was from 3.6 to 28.2% with a very large variation and average 14.9%. By the climate change RCP 8.5 scenario, the annual precipitation from 2019 to 2100 was 572.8-1996.5 mm (average 1078.4 mm) and groundwater recharge of 26.7-432.5 mm (average precipitation 16.2%). The annual groundwater recharge rates in the future were projected from 2.8% to 45.1%, 18.2% on average. The components that make up the water balance were well correlated with precipitation, especially in the annual data rather than the daily data. However, the amount of evapotranspiration seems to be more affected by other climatic factors such as temperature. Groundwater recharge in more detailed time scale rather than annual scale is expected to provide basic data that can be used for groundwater development and management if precipitation are severely varied by time, such as droughts or floods.