• 한국농공학회논문집
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• 제57권5호
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• pp.1-12
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• 2015

The study aimed to project inflows and demmands for the agricultural reservoir watersheds in South Korea considering a variety of regional characteristics and the uncertainty of future climate information. The study bias-corrected and spatially downscaled retrospective daily Global Climate Model (GCM) outputs under Representative Concentration Pathways (RCP) 4.5 and 8.5 emission scenarios using non-parametric quantile mapping method to force Soil and Water Assessment Tool (SWAT) model. Using the historical simulation, the skills of un-calibrated SWAT model (without calibration process) was evaluated for 5 reservoir watersheds (selected as well-monitored representatives). The study then, evaluated the performance of 9 GCMs in reproducing historical upstream inflow and irrigation demand at the five representative reservoirs. Finally future inflows and demands for 58 watersheds were projected using 9 GCMs projections under the two RCP scenarios. We demonstrated that (1) un-calibrated SWAT model is likely applicable to agricultural watershed, (2) the uncertainty of future climate information from different GCMs is significant, (3) multi-model ensemble (MME) shows comparatively resonable skills in reproducing water balances over the study area. The results of projection under the RCP 4.5 and RCP 8.5 scenario generally showed the increase of inflow by 9.4% and 10.8% and demand by 1.4% and 1.7%, respectively. More importantly, the results for different seasons and reservoirs varied considerably in the impacts of climate change.

• 대한공간정보학회지
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• 제21권2호
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• pp.107-116
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• 2013

본 연구는 새로운 기후변화 시나리오인 RCP 시나리오의 스토리라인을 기반으로 미래 토지피복변화를 예측하고, RCP 시나리오하의 미래 기후 및 토지피복 변화가 유역 내 유출량에 미치는 영향을 분석하는데 그 목적을 둔다. RCP 4.5 및 8.5하의 기후 자료가 기후변화 시나리오로 사용되었고, 토지피복변화 시나리오는 RCP 4.5 및 8.5 시나리오의 스토리라인과 로지스틱 회귀모형(LR)을 이용하여 개발된 모델에 의해 생성되었다. 기후변화만 고려한 경우, 토지피복변화만 고려한 경우로 두 가지 시나리오를 설정하고, 각각의 시나리오에 따른 대상 유역 내 유출량을 모의한 결과는 유출량의 계절적 변화를 뚜렷이 나타내었다. 기후변화는 봄과 겨울에 유출량을 증가, 여름과 가을에 유출량을 감소시키는 것으로 예측되었다. 반면 토지피복변화는 기후변화에 비해 상대적으로 유역 내 유출량 변화에 미소한 영향을 주지만, 강수 유무에 따라 유출량의 증가 및 감소 패턴이 뚜렷이 나타났다. 따라서 수자원 정책결정에 있어서 미래 토지피복변화에 따른 홍수 및 가뭄의 패턴에 적합한 수자원 정책이 필요할 것으로 판단된다.

• 환경생물
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• 제34권4호
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• pp.240-245
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• 2016

본 연구에서 외래식물인 청비름(Amaranthus viridis L.)의 현재의 잠재 서식지와 RCP 4.5와 RCP 8.5에 의한 미래의 분포 확산을 MaxEnt 모델을 활용하여 예측하였다. 청비름의 잠재 서식지는 연평균기온, 고도, 12월의 강수량의 환경변수가 85% 이상의 기여도를 보여 가장 중요한 변수로 분석되었고 AUC도 0.95로 모형의 설명력이 높게 나타났다. 제주도와 남해안 및 중남부 서해안을 중심으로 분포하고 있는 청비름은 RCP 4.5에서는 확산이 크게 나타나지 않으나, RCP 8.5 시나리오는 잠재 서식지가 전국으로 확산되는 것으로 나타났고 현재에 비하여 2090년대 잠재 서식지 비율이 약 4.8배 증가하는 것으로 분석되었다. 이러한 시나리오 별 차이는 향후 청비름의 확산이 기후변화 양상에 따라 가변적일 수 있음을 보여준다. 청비름은 많은 종자 생산과 차량의 이동이나 사람의 이동 중에 쉽게 확산되는 특성이 있어 잠재서식지 비율의 증가는 실제 확산으로 이어질 수 있을 것으로 파악된다. 빠르게 확산될 수 있을 것이다. 같은 비름속의 개비름과 가는털비름은 이미 전국에 분포하고 있어 관리가 어려운 실정이고 기후변화에 의한 온도 상승은 청비름 또한 전국적으로 확산될 가능성을 가지고 있어 장기적인 관심과 관리기술 개발이 필요한 시점이다. 본 연구에서 수행한 지역별 예측은 향후 관리 계획 설정 등에 활용 가능할 것으로 판단된다.

• 한국농공학회논문집
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• 제57권4호
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• pp.73-84
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• 2015

An embankment raising project on 113 agricultural reservoirs in Korea was implemented in 2009 to increase water supply capacity for agricultural water and instream uses. This study evaluated the future water supply capacity of the Imgo reservoir at which the agricultural reservoir embankment raising project was completed, considering climate change scenarios. The height of the embankment of the reservoir was increased by 4.5 m, thereby increasing its total storage from 1,657.0 thousand to 3,179.5 thousand cubic meters. To simulate the reservoir water storage with respect to climate changes, two climate change scenarios, namely, RCP 4.5 and RCP 8.5 (in which greenhouse gas reduction policy was executed and not executed, respectively) were applied with bias correction for reflecting the climate characteristics of the target basin. The analysis result of the agricultural water supply capacity in the future, after the agricultural reservoir embankment raising project is implemented, revealed that the water supply reliability and the agricultural water supply increased, regardless of the climate change scenarios. By simulating the reservoir water storage considering the instream flow post completion of the embankment raising project, it was found that water shortage in the reservoir in the future is not likely to occur when it is supplied with an appropriate instream flow. The range of instream flow tends to decrease over time under RCP 8.5, in which the greenhouse gas reduction policy was not executed, and the restoration of reservoir storage was lower in this scenario than in RCP 4.5, in which greenhouse gas reduction policy was executed.

• 대한원격탐사학회지
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• 제37권5_1호
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• pp.833-845
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• 2021

탄소흡수량 산정 및 토지이용 변화에 대한 이해는 기후변화 연구에서 매우 중요하다. 기존의 연구에서는 토지이용 변화에 따른 탄소흡수량 산정에 원격탐사 기술이 사용되고 있으나 대부분 과거의 탄소흡수량 변화에 초점을 맞추고 있다. 따라서 미래 탄소흡수량 변화 예측 연구는 부족한 실정이다. 본 연구에서 CLUE-S 모형을 사용하여 토지이용 변화를 모의하고 기후변화 시나리오를 고려하여 미래 탄소흡수량의 변화를 예측하였다. 그 결과, RCP 4.5 및 8.5 시나리오에서 탄소흡수량은 각각 7.92, 13.02% 감소되는 것으로 예측되었다. 따라서 본 연구에서 제안한 방법은 다른 기후변화 시나리오를 고려한 미래 탄소흡수량 변화에도 적용이 가능할 것으로 기대된다.

• 대기
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• 제25권4호
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• pp.693-706
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• 2015

A shift of first fowering date (FFD) of spring blossoms (cherry, peach and pear) over the northest Asia under global warming is investiaged using dynamically downscaled daily temperature data with 12.5 km resolution. For the study, we obatained gridded daily data with Historical (1981~2010), and Representative Concentration Pathway (RCP) (2021~2100) 4.5 and 8.5 scenarios which were produced by WRFv3.4 in conjunction with HadGEM2-AO. A change on FFDs in 21st century is estimated by applying daily outputs of WRFv3.4 to DTS phonological model. Prior to projection on future climate, the performances of both WRFv3.4 and DTS models are evaluated using spatial distribution of climatology and SCR diagram (Normalized standard deviation-Pattern correlation coefficient-Root mean square difference). According to the result, WRFv3.4 and DTS models well simulated a feature of the terrain following characteristics and a general pattern of observation with a marigin of $1.4^{\circ}C$ and 5~6 days. The analysis reveals a projected advance in FFDs of cherry, peach and pear over the northeast Asia by 2100 of 15.4 days (9.4 days). 16.9 days (10.4 days) and 15.2 days (9.5 days), respectively, compared to the Historical simulation due to a increasing early spring (Februrary to April) temperature of about $4.9^{\circ}C$ ($2.9^{\circ}C$) under the RCP 8.5 (RCP 4.5) scenarios. This indicates that the current flowering of the cherry, peach and pear over analysis area in middle or end of April is expected to start blooming in early or middle of April, at the end of this century. The present study shows the dynamically downscaled daily data with high-resolution is helpeful in offering various useful information to end-users as well as in understanding regional climate change.

• 한국환경복원기술학회지
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• 제18권2호
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• pp.79-88
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• 2015

Preparations need to be made for Korean pine(Pinus koraiensis) in anticipation of climate change because Korean pine is an endemic species of South Korea and the source of timber and pine nut. Therefore, climate change adaptation policy has been established to conduct an impact assessment on the distribution of Korean pine. Our objective was to predict the distribution of Korean pine while taking into account uncertainty and afforestation conditions. We used the 5th forest types map, a forest site map and BIOCLIM variables. The climate scenarios are RCP 4.5 and RCP 8.5 for uncertainty and the climate models are 5 regional climate models (HadGEM3RA, RegCM4, SNURCM, GRIMs, WRF). The base period for this study is 1971 to 2000. The target periods are the mid-21st century (2021-2050) and the end of the 21st century (2071-2100). This study used the MaxEnt model, and 50% of the presences were randomly set as training data. The remaining 50% were used as test data, and 10 cross-validated replicates were run. The selected variables were the annual mean temperature (Bio1), the precipitation of the wettest month (Bio13) and the precipitation of the driest month (Bio14). The test data's ROC curve of Korean pine was 0.689. The distribution of Korean pine in the mid-21st century decreased from 11.9% to 37.8% on RCP 4.5 and RCP 8.5. The area of Korean pine at an artificial plantation occupied from 32.1% to 45.4% on both RCPs. The areas at the end of the 21st century declined by 53.9% on RCP 4.5 and by 86.0% on RCP 8.5. The area of Korean pine at an artificial plantation occupied 23.8% on RCP 4.5 and 7.2% on RCP 8.5. Private forests showed more of a decrease than national forests for all subsequent periods. Our results may contribute to the establishment of climate change adaptation policies for considering various adaptation options.

• 한국수자원학회논문집
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• 제52권9호
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• pp.647-655
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• 2019

남한과 북한이 군사분계선을 경계로 공동으로 점유하고 있는 남북공유하천유역은 과거부터 하천관리, 홍수조절 등 다양한 문제가 지속적으로 발생해 왔다. 그러나 협력과 조정에 한계가 있어 유역 관리에 대한 지속적인 연구와 협력이 진행되지 못하였다. 기후변화로 인해 수문현상의 규모와 빈도가 변화하고 있어 공유하천유역의 강수변동성에 관한 대비책 마련이 필요하지만, 이에 대한 연구는 미비한 실정이다. 따라서 본 연구에서는 13개 전 지구 기후 모델의 RCP (Representative Concentration Pathway, 이하 RCP)4.5와 RCP8.5 시나리오를 공유하천유역 인접 11개 관측소에 적용하여 극한강수량 변동성을 규모와 빈도의 측면에서 분석하였다. 분석 결과 공유하천유역의 참조기간(1981-2005) 대비 확률강우량은 RCP4.5 시나리오와 RCP8.5 시나리오 모두 전 기간에서 증가하였다. 또한 재현기간 20년 규모의 강우 빈도는 RCP4.5 시나리오의 중반기(2041-2070)와 후반기(2071-2100)를 제외하고 전 기간에서 증가하여 극한강수의 출현빈도가 점차 빨라지고 있음을 확인할 수 있었다. 결과적으로 공유하천유역 내 극한강수량은 그 규모와 빈도가 모두 증가하여 기후변화로 인한 상당한 영향이 있을 것으로 전망되며, 이에 대한 대비가 필요할 것으로 판단된다.

• 한국농공학회논문집
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• 제62권6호
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• pp.85-95
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• 2020

According to the standard guidelines of design flood (MLTM, 2012; MOE, 2019), the design flood is calculated based on past precipitation. However, due to climate change, the frequency of extreme rainfall events is increasing. Therefore, it is necessary to analyze future floods' volume by using climate change scenarios. Meanwhile, the standard guideline was revised by MOE (Ministry of Environment) recently. MOE proposed modified Huff distribution and new CN (Curve Number) value of forest and paddy. The objective of this study was to analyze the change of flood volume by applying the modified Huff and newly proposed CN to the probabilistic precipitation based on SSP and RCP scenarios. The probabilistic rainfall under climate change was calculated through RCP 4.5/8.5 scenarios and SSP 245/585 scenarios. HEC-HMS (Hydrologic Engineering Center - Hydrologic Modeling System) was simulated for evaluating the flood volume. When RCP 4.5/8.5 scenario was changed to SSP 245/585 scenario, the average flood volume increased by 627 ㎥/s (15%) and 523 ㎥/s (13%), respectively. By the modified Huff distribution, the flood volume increased by 139 ㎥/s (3.76%) on a 200-yr frequency and 171 ㎥/s (4.05%) on a 500-yr frequency. The newly proposed CN made the future flood value increase by 9.5 ㎥/s (0.30%) on a 200-yr frequency and 8.5 ㎥/s (0.25%) on a 500-yr frequency. The selection of climate change scenario was the biggest factor that made the flood volume to transform. Also, the impact of change in Huff was larger than that of CN about 13-16 times.

• Journal of Forest and Environmental Science
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• 제39권2호
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• pp.105-117
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• 2023

Climate change and invasive alien plant species (IAPs) are having a significant impact on mountain ecosystems. The combination of climate change and socio-economic development is exacerbating the invasion of IAPs, which are a major threat to biodiversity loss and ecosystem functioning. Species distribution modelling has become an important tool in predicting the invasion or suitability probability under climate change based on occurrence data and environmental variables. MaxEnt modelling was applied to predict the current suitable distribution of most noxious weed A. adenophora (Spreng) R. King and H. Robinson and analysed the changes in distribution with the use of current (year 2000) environmental variables and future (year 2050) climatic scenarios consisting of 3 representative concentration pathways (RCP 2.6, RCP 4.5 and RCP 8.5) in Bhutan. Species occurrence data was collected from the region of interest along the road side using GPS handset. The model performance of both current and future climatic scenario was moderate in performance with mean temperature of wettest quarter being the most important variable that contributed in model fit. The study shows that current climatic condition favours the A. adenophora for its invasion and RCP 2.6 climatic scenario would promote aggression of invasion as compared to RCP 4.5 and RCP 8.5 climatic scenarios. This can lead to characterization of the species as preferring moderate change in climatic conditions to be invasive, while extreme conditions can inhibit its invasiveness. This study can serve as reference point for the conservation and management strategies in control of this species and further research.