• 제목/요약/키워드: Environmental Change

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Analysis on Urban Sprawl and Landcover Change Using TM, ETM+ and GIS

  • Xiao, Jieying;Ryutaro, Tateishi;Shen, Yanjun;Ge, Jingfeng;Liang, Yanqing;Chang, Chunping
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.978-980
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    • 2003
  • This study explores the temporal and spatial features near 67years (1934 ?2001) and landcover change in last 14 years (1987-2001) in Shijiazhuang, China, based on 67-year time series data edited from historical maps, TM and ETM+ imageries by integrating GIS and remote sensing method. An index named Annual Growth Rate (AGR) is used to analyze the spatial features of urban sprawl, and Maximum Likelihood classification method is utilized to detect the land cover types change. At last, the relationship between urbanization and factors is analyzed.

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IPCC SRES A2와 B1 시나리오에 따른 한반도지역의 여름철 지표 오존의 수치모의 (Simulations of Summertime Surface Ozone Over the Korean Peninsula Under IPCC SRES A2 and B1 Scenarios)

  • 홍성철;최진영;송창근;홍유덕;이석조;이재범
    • 한국대기환경학회지
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    • 제29권3호
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    • pp.251-263
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    • 2013
  • The surface ozone concentrations changes were investigated in response to climate change over the Korean peninsula for summertime using the global-regional one way coupled Integrated Climate and Air quality Modeling System (ICAMS). The future simulations were conducted under the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A2 and B1 scenarios. The modeling system was applied for four 10-year simulations: 1996~2005 as a present-day case, 2016~2025, 2046~2055, and 2091~2100 as future cases. The results in this study showed that the mean surface ozone concentrations increased up to 0.5~3.3 ppb under the A2, but decreased by 0.1~10.9 ppb under the B1 for the future, respectively. However, its increases were lower than an increase of the average daily maximum 8-hour (DM8H) surface ozone concentrations which was projected to increase by 2.8~6.5 ppb under the A2. The DM8H surface ozone concentrations seem to be therefore far more affected by the climate and emissions changes than mean values. The probability of exceeding 60 ppb was projected to increase by 6~19% under the A2. In the case of B1, its changes were presented with an increase of 2.9% in the 2020s but no occurrence in the 2100s due to the effect of the reduced emissions. Future projection on surface ozone concentrations was generally shown to have almost the similar trend as the emissions of $NO_x$ and NMVOC.

IPCC SRES 시나리오에 따른 우리나라의 미래 냉난방도일 전망: CCSM3와 MM5 모델 활용 (Projection of Future Heating and Cooling Degree Days over South Korea under the IPCC SRES Scenarios: An Experiment with CCSM3 and MM5 Models)

  • 최진영;송창근;김덕래;홍성철;홍유덕;이재범
    • 한국기후변화학회지
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    • 제4권2호
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    • pp.141-158
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    • 2013
  • 본 연구에서는 IPCC SRES 6개 기후변화 시나리오(A2, A1B, A1FI, A1T, B1, and B2)를 기반으로 우리나라의 현재(1996~2005년)와 미래(2046~2055년, 2091~2100년)에 대한 냉난방도일을 전망하였다. 이를 위하여 전구 기후모델(CCSM3)의 미래 전망 결과를 지역규모 기후모델(MM5)을 이용한 다운스케일링을 통해 고해상도(18km)의 기온 전망을 수행하였다. 21세기 말의 한반도 기온은 현재 대비 약 $1.2{\sim}3.4^{\circ}C$ 수준까지 증가하는 것으로 전망된다. 기온 전망 결과를 이용하여 7개 권역별(서울 경기, 강원 산간, 중부 내륙, 남부 내륙, 남부 해안, 영동 울릉, 제주) 냉난방도일을 전망한 결과, 21세기 말의 난방도일은 현재 대비 8~25% 수준까지 감소하는 반면에 냉방도일은 242~1,448%까지 증가하였다. 또한, 난방기간은 약 1개월 정도 감소하며, 냉방기간은 최대 2개월 이상 증가하는 것으로 나타났다. 따라서 현재에 비해 미래의 난방에너지 수요는 감소하지만, 냉방에너지 수요는 증가할 것으로 예측된다. 특히, 이러한 변화는 타 권역에 비해 강원산간권역과 제주권역에서 뚜렷하게 나타날 것으로 예측된다. 따라서 미래에는 난방을 위한 화석에너지보다 냉방에너지로 사용되는 전기에너지에 대한 수요관리가 현재보다 더욱 중요해질 수 있음을 의미한다.

Estimating Wood Weight Change on Air Drying Times for Three Coniferous Species of South Korea

  • Lee, Daesung;Choi, Jungkee
    • Journal of Forest and Environmental Science
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    • 제32권3호
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    • pp.262-269
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    • 2016
  • The purposes of this study are to calculate the green and dried weight using wood discs, to figure out weight change on air drying times, and to develop the model of wood disc weight change for Larix kaempferi, Pinus koraiensis, and Pinus densiflora. The variables affecting the weight change were investigated, and the pattern of weight change over time was figured out through linear models. When comparing the stem green weight calculated using wood discs in this study with the weight table of Korea Forest Service, the weight was not significantly different for L. kaempferi and P. koraiensis. On the other hand, in comparison of stem dried weight, the weight was significantly different in all of three species. In addition, various measurement factors were examined to figure out the relationship with weight change, and air drying times and disc diameter were found as significant independent variables. Finally, two linear models were developed to estimate air drying times of three species, fit statistics were significant for practical use.

Establishment of Best Management Indicator for Sustainable Agricultural Water Quality using Delphi Survey Method

  • Kim, Min-Kyeong;Jung, Goo-Bok;Hong, Seong-Chang;Kim, Myung-Hyun;Choi, Soon-Kun;Kwon, Soon-Ik;So, Kyu-Ho
    • 한국토양비료학회지
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    • 제48권5호
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    • pp.379-383
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    • 2015
  • Indicators of environmental conditions describe the state of the environment and the quantity and quality of natural resources. This study deduced the evaluation items to assess each sub-indicator for agricultural water quality and conducted the surveying using the Delphi method based on agricultural water quality experts. Considering its importance, environmental, state, and management indicators showed that state indicator such as COD concentration for surface water and $NO_3-N$ concentration for groundwater was ranked as first and followed by amount of fertilizer. Its indicators were correlated with state and environmental indicators in surface water and groundwater. The best management indicators were calculated to assess the agricultural surface water and ground water quality. The indicator could be used in established policies for management and conservation of water resources.

Management Strategy of Sediment-Related Disasters for Adaptation to Climate Change

  • Chun, Kun-Woo;Kim, Suk-Woo;Lee, Youn-Tae
    • Journal of Forest and Environmental Science
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    • 제34권2호
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    • pp.192-195
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    • 2018
  • To establish a management strategy of sediment-related disasters for adaptation to climate change, it is necessary to 1) understand the specific details and problems about the present status, 2) systematize related technologies by using exact numerical values obtained from physically-based analysis, and 3) ensure the basic guidelines are applied to field elastically. To achieve these successfully, detailed guidelines are required by scientifically considering the utilization and impact of related technology on the field. Here, detailed guidelines should include 1) the development of a basic plan, 2) enhancement of relevant technical instructions, 3) establishment of survey and inspection methods, 4) procedure of erosion control works in urban living sphere, and 5) proactive countermeasures against sediment-related disaster caused by earthquakes.

기후변화 리스크의 지역 불평등 모니터링 : 폭염을 중심으로 (Monitoring regional inequalities in climate change risk - A Focus on Heatwave -)

  • 김근한
    • 한국환경복원기술학회지
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    • 제24권6호
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    • pp.97-107
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    • 2021
  • Abnormal climate caused by climate change causes enormous social and economic damage. And such damage and its impact may vary depending on the location and regional characteristics of the region and the social and economic conditions of local residents. Therefore, it is necessary to continuously monitor whether there are indicators that are weaker than other regions among the detailed indicators that constitute the risk, exposure and vulnerability of climate change risk. In this study, the concept of climate change risk was used for heatwave to determine regional inequality of climate change risk. In other words, it was judged that inequality in climate change risk occurred in regions with high risk but high exposure and low vulnerability compared to other regions. As a result of the analysis, it was found that 13 local governments in Korea experienced regional inequality in climate change risk. In order to resolve regional inequality in climate change risks, the current status of regional inequality in climate change should be checked based on the analysis proposed in this study, there is a need for an evaluation and monitoring system that can provide appropriate feedback on areas where inequality has occurred. This continuous evaluation and monitoring-based feedback system is expected to be of great help in resolving regional inequality in climate change risks.

기후변화시나리오와 비정상성 빈도분석을 이용한 도시유형별 목표연도 설계강우량 제시 및 치수안전도 변화 전망 (Predicting the Design Rainfall for Target Years and Flood Safety Changes by City Type using Non-Stationary Frequency Analysis and Climate Change Scenario)

  • 정세진;강동호;김병식
    • 한국환경과학회지
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    • 제29권9호
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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.

Automatic Change Detection Using Unsupervised Saliency Guided Method with UAV and Aerial Images

  • Farkoushi, Mohammad Gholami;Choi, Yoonjo;Hong, Seunghwan;Bae, Junsu;Sohn, Hong-Gyoo
    • 대한원격탐사학회지
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    • 제36권5_3호
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    • pp.1067-1076
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    • 2020
  • In this paper, an unsupervised saliency guided change detection method using UAV and aerial imagery is proposed. Regions that are more different from other areas are salient, which make them more distinct. The existence of the substantial difference between two images makes saliency proper for guiding the change detection process. Change Vector Analysis (CVA), which has the capability of extracting of overall magnitude and direction of change from multi-spectral and temporal remote sensing data, is used for generating an initial difference image. Combined with an unsupervised CVA and the saliency, Principal Component Analysis(PCA), which is possible to implemented as the guide for change detection method, is proposed for UAV and aerial images. By implementing the saliency generation on the difference map extracted via the CVA, potentially changed areas obtained, and by thresholding the saliency map, most of the interest areas correctly extracted. Finally, the PCA method is implemented to extract features, and K-means clustering is applied to detect changed and unchanged map on the extracted areas. This proposed method is applied to the image sets over the flooded and typhoon-damaged area and is resulted in 95 percent better than the PCA approach compared with manually extracted ground truth for all the data sets. Finally, we compared our approach with the PCA K-means method to show the effectiveness of the method.