• Title/Summary/Keyword: geographic environment

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Analyzing Residential Land Use Change and Population Density Considering Climate Change Using Land Use Equilibrium Model in Jeju (토지이용균형모델을 이용한 기후변화에 따른 제주도 지역의 주거용 토지이용변화와 인구 밀도 예측)

  • YOO, So-Min;LEE, Woo-Kyun;Yamagata, Yoshiki;Lim, Chul-Hee;SONG, Chol-Ho;CHOI, Hyun-Ah
    • Journal of the Korean Association of Geographic Information Studies
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    • v.18 no.4
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    • pp.43-58
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    • 2015
  • The greenhouse gas emission caused by rapid economic growth and population is increasing in Korea. Also, climate change from greenhouse gases emission is accelerated. IPCC(Intergovernmental Panel on Climate Change) report projects an increase of greenhouse gas emissions by 90% from the year 2000 to 2030(SRES, 2000). Within this context, establishing countermeasures on climate adaptation and mitigation is becoming increasingly important to reduce the negative effect of climate change at a global level. Along with global efforts to tackle climate change, Korean government has incorporated 'Low Carbon Green Growth'strategies into its national policy agenda. Local governments have also conducted a number of studies to devise plans for environmentally friendly and sustainable city development. In this paper, the land-use equilibrium model, which reflects economic and geographical characteristics, is used to analyze the change in residential land use and population density. The target area for study is Jeju island in Korea. With an application of land use equilibrium model, it derived three types of scenarios of the land use change: (1) dispersion scenario-reflecting present-day conditions (2) adaptation scenario-applying adaptation measures to climate change and (3) combined scenario-integrating both adaptation and mitigation measures in model to climate change. By applying dispersion to combined scenario, the general trend shows a downward shift in population density. Subsequently, energy consumption and expected cost associated with casualties were calculated on the basis of the findings of respective scenario. The results show a descending trend in energy consumption and expected casualtie. Therefore, understanding for residential land use and population density of each scenario that analyzed land use equilibrium model in the study is expected to devise a environmental city plan for climate change stabilization and climate adaptation and mitigation.

Estimation of Urban Heat Island Potential Based on Land Cover Type in Busan Using Landsat-7 ETM+ and AWS Data (Landsat-7 ETM+ 영상과 AWS 자료를 이용한 부산의 토지피복에 따른 여름철 도시열섬포텐셜 산출)

  • Ahn, Ji-Suk;Hwang, Jae-Dong;Park, Myung-Hee;Suh, Young-Sang
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.4
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    • pp.65-77
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    • 2012
  • This study examined changes in land cover for the past 25 years in Busan and subsequently evaluated heat island potential by using land surface temperature and observation temperature data. The results were as below. The urban area of Busan increased by more than 2.5 times for the past 25 years from 1975 to 2000. It was believed that an increase in the pavement area of city within such a short period of time was an unprecedented phenomenon unique to our country. It could be assumed that urban heat island would be worsened through this process. After analyzing the land temperature according to the land cover, it was shown that there were noticeable changes in the temperature of urban & built-up and mountain & forest areas. In particular, the temperature rose to $36{\sim}39^{\circ}C$ in industrial areas during the summer, whereas it went down to $22{\sim}24^{\circ}C$ in the urban areas at whose center there were mountains. It was found that heat island potential according to the level of land cover had various values depending on the conditions of land cover. Among the areas of urbanization, the industrial area's heat island potential is 6 to $8^{\circ}C$, and the residential and commercial area's is $0{\sim}5^{\circ}C$, so it has been found that there is high possibility to induce urban heat islands. Meanwhile, in the forest or agricultural area or the waterside, the heat island potential is $-6{\sim}-3^{\circ}C$. With this study result, it is possible to evaluate the effects of temperature increase according to the urban land use, and it can be used as foundational data to improve urban thermal environment and plan eco-friendly urban development.

Overview of Research Trends in Estimation of Forest Carbon Stocks Based on Remote Sensing and GIS (원격탐사와 GIS 기반의 산림탄소저장량 추정에 관한 주요국 연구동향 개관)

  • Kim, Kyoung-Min;Lee, Jung-Bin;Kim, Eun-Sook;Park, Hyun-Ju;Roh, Young-Hee;Lee, Seung-Ho;Park, Key-Ho;Shin, Hyu-Seok
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.3
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    • pp.236-256
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    • 2011
  • Forest carbon stocks change due to land use change is an important data required by UNFCCC(United Nations framework convention on climate change). Spatially explicit estimation of forest carbon stocks based on IPCC GPG(intergovernmental panel on climate change good practice guidance) tier 3 gives high reliability. But a current estimation which was aggregated from NFI data doesn't have detail forest carbon stocks by polygon or cell. In order to improve an estimation remote sensing and GIS have been used especially in Europe and North America. We divided research trends in main countries into 4 categories such as remote sensing, GIS, geostatistics and environmental modeling considering spatial heterogeneity. The easiest way to apply is combination NFI data with forest type map based on GIS. Considering especially complicated forest structure of Korea, geostatistics is useful to estimate local variation of forest carbon. In addition, fine scale image is good for verification of forest carbon stocks and determination of CDM site. Related domestic researches are still on initial status and forest carbon stocks are mainly estimated using k-nearest neighbor(k-NN). In order to select suitable method for forest in Korea, an applicability of diverse spatial data and algorithm must be considered. Also the comparison between methods is required.

Updating DEM for Improving Geomorphic Details (미기복 지형 표현을 위한 DEM 개선)

  • Kim, Nam-Shin
    • Journal of the Korean Association of Geographic Information Studies
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    • v.12 no.1
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    • pp.64-72
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    • 2009
  • The method to generate a digital elevation model(DEM) from contour lines causes a problem in which the low relief landform cannot be clearly presented due to the fact that it is significantly influenced by the expression of micro landform elements according to the interval of contours. Thus, this study attempts to develop a landcover burning method that recovers the micro relief landform of the DEM, which applies buffering and map algebra methods by inputting the elevation information to the landcover. In the recovering process of the micro landform, the DEM was recovered using the buffering method and elevation information through the map algebra for the landcover element for the micro landform among the primary DEM generation, making landcover map, and landcover elements. The recovering of the micro landform was applied based on stream landforms. The recovering of landforms using the buffering method was performed for the bar, which is a polygonal element, and wetland according to the properties of concave/convex through generating contours with a uniform interval in which the elevation information applied to the recovered landform. In the case of the linear elements, such as bank, road, waterway, and tributary, the landform can be recovered by using the elevation information through applying a map algebra function. Because the polygonal elements, such as stream channel, river terrace, and artificial objects (farmlands) are determined as a flat property, these are recovered by inputting constant elevation values. The results of this study were compared and analyzed for the degree of landform expression between the original DEM and the recovered DEM. In the results of the analysis, the DEM produced by using the conventional method showed few expressions in micro landform elements. The method developed in this study well described wetland, bar, landform around rivers, farmland, bank, river terrace, and artificial objects. It can be expected that the results of this study contribute to the classification and analysis of micro landforms, plain and the ecology and environment study that requires the recovering of micro landforms around streams and rivers.

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Validation of ENVI-met Model with In Situ Measurements Considering Spatial Characteristics of Land Use Types (토지이용 유형별 공간특성을 고려한 ENVI-met 모델의 현장측정자료 기반의 검증)

  • Song, Bong-Geun;Park, Kyung-Hun;Jung, Sung-Gwan
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.2
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    • pp.156-172
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    • 2014
  • This research measures and compares on-site net radiation energy, air temperature, wind speed, and surface temperature considering various spatial characteristics with a focus on land use types in urban areas in Changwon, Southern Gyeongsangnam-do, to analyze the accuracy of an ENVI-met model, which is an analysis program of microclimate. The on-site measurement was performed for three days in a mobile measurement: two days during the daytime and one day during the nighttime. The analysis using the ENVI-met model was also performed in the same time zone as the on-site measurement. The results indicated that the ENVI-met model showed higher net radiation than the on-site measurement by approximately $300Wm^{-2}$ during the daytime whereas the latter showed higher net radiation energy by approximately $200Wm^{-2}$ during the nighttime. The temperature was found to be much higher by approximately $2-6^{\circ}C$ in the on-site measurement during both the daytime and nighttime. The on-site measurement also showed higher surface temperature than the ENVI-met by approximately $7-13^{\circ}C$. In terms of the wind speed, there was a significant difference between the results of the ENVI-met model and on-site measurement. As for the correlation between the results of the ENVI-met model and on-site measurement, the temperature showed significantly high correlation whereas the correlations for the net radiation energy, surface temperature, and wind speed were very low. These results appear to be affected by excessive or under estimation of solar and terrestrial radiation and climatic conditions of the surrounding areas and characteristics of land cover. Hence, these factors should be considered when applying these findings in urban and environment planning for improving the microclimate in urban areas.

The Relationship Analysis between the Epicenter and Lineaments in the Odaesan Area using Satellite Images and Shaded Relief Maps (위성영상과 음영기복도를 이용한 오대산 지역 진앙의 위치와 선구조선의 관계 분석)

  • CHA, Sung-Eun;CHI, Kwang-Hoon;JO, Hyun-Woo;KIM, Eun-Ji;LEE, Woo-Kyun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.19 no.3
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    • pp.61-74
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    • 2016
  • The purpose of this paper is to analyze the relationship between the location of the epicenter of a medium-sized earthquake(magnitude 4.8) that occurred on January 20, 2007 in the Odaesan area with lineament features using a shaded relief map(1/25,000 scale) and satellite images from LANDSAT-8 and KOMPSAT-2. Previous studies have analyzed lineament features in tectonic settings primarily by examining two-dimensional satellite images and shaded relief maps. These methods, however, limit the application of the visual interpretation of relief features long considered as the major component of lineament extraction. To overcome some existing limitations of two-dimensional images, this study examined three-dimensional images, produced from a Digital Elevation Model and drainage network map, for lineament extraction. This approach reduces mapping errors introduced by visual interpretation. In addition, spline interpolation was conducted to produce density maps of lineament frequency, intersection, and length required to estimate the density of lineament at the epicenter of the earthquake. An algorithm was developed to compute the Value of the Relative Density(VRD) representing the relative density of lineament from the map. The VRD is the lineament density of each map grid divided by the maximum density value from the map. As such, it is a quantified value that indicates the concentration level of the lineament density across the area impacted by the earthquake. Using this algorithm, the VRD calculated at the earthquake epicenter using the lineament's frequency, intersection, and length density maps ranged from approximately 0.60(min) to 0.90(max). However, because there were differences in mapped images such as those for solar altitude and azimuth, the mean of VRD was used rather than those categorized by the images. The results show that the average frequency of VRD was approximately 0.85, which was 21% higher than the intersection and length of VRD, demonstrating the close relationship that exists between lineament and the epicenter. Therefore, it is concluded that the density map analysis described in this study, based on lineament extraction, is valid and can be used as a primary data analysis tool for earthquake research in the future.

The International Geographical Symposium for the 50th anniversary of the Korean geographical society:the pressing problems in Korean geography (대한지리학회 창립 50주년 기념 국제지리학술대회와 지리학의 당면 과제)

  • ;Lee, Hak-Won
    • Journal of the Korean Geographical Society
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    • v.30 no.2
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    • pp.188-199
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    • 1995
  • This International Geographical Symposium is to comemorate the 50th anniversary of the Korean Geographical Society. The Korean Geographical Society (KGS) which is the headquater of the geogaphical study will be play a main role to promote International Geographical Conference(IGC). And KGS hopes to prepare for the success of IGC and to examine the ability of the Korean Geographical Society for holding IGC in Seoul, in 2000. Above all, we expect to confirm what vision of the spatial structure our geographers have had for the last 50 years and in the position of the Korean Geographical Society, we present various studies on the spatial structure of the Unified Korea and through the discussion of the members we are going to lead our common interest to the key of reunification and motivate this studies more actively. We think that German geographers who have been studying the establishment of the spatial structure before and after the reunification of Germany will help in setting spatial structure of reunified Korea. In the second part of seminar, we will have a lecture on "Geography in the 21st Century; its Perspectives and Contribution". This lecture will prepose the trends of international geographical study and discipline, to Korean geographers and encourage them to realize what position we are in on the level of international geography and intensify their study. In the end of twentieth centuries, Korean geographers, who accessto postmodernism, hope to develope the unique subject matter and discipline regrardless of the 50 year-partition of the Korean Peninsula through the study of geobraphy. What can we suagest to geographers under the unique spatia1 structure of the divided peninsula\ulcorner How will our country develope in the future when DMZ, the last remains of cold war, vanishes and our reunified country becomes\ulcorner These subject matters will be issued in this International Geographic Conference. These issued subject matters and procedures of discussion will stimulate younger students to have interest in our unique geographic environment and to set up thier own method of study. In the third part of seminar, a special lecture on "Half-century of Korean Geography: It's Reflection and Perspective", the product and the subject of each part in geography will be discussed. Because this seminar is for the first time in 20 years after the 30th anniversary, the evaluation and the comment of each field in geography will be focused on because the achievement of each member's study is evaluted and refered to objectively. The newly developed field ewll be proposed, as well as the evaluation and the result of the Korean Geographical Society. The criticism and the proposal of the Korean Geographical Society will encourage the study of each member. And it will contribute to the development of the Korean Geographical Society. We hope all the issued papers to be published as atreatise and circulated to all members, university liberaries, each institution etc. There is no doubt our research and study will affect geographers and geography teachers to use this treatise. If possible, we will make public editions to distribute widely for students who study geography. It will help students to study geography encouragingly and to understand a correct structure and to commit themselves to promote the developed industrial country when they are playing a leading part in society. And we will contribute this issue to all the institutes such as the congress, each department of government, the political parties, the economic circles and private institutes, in order to make them understand our academic efforts and activities. Besides, we hope this contribution will give them much understanding and interest about 2000 IGC in Seoul beforehand.in Seoul beforehand.

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Analysis Schemes of Wind Ventilation Forest Types - A Case Study of Daegu Metropolitan City - (바람길숲의 유형별 분석 방안 - 대구광역시를 사례로 -)

  • EUM, Jeong-Hee;OH, Jeong-Hak;SON, Jeong-Min;KIM, Kwon;BAEK, Jun-Beom;YI, Chaeyeon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.4
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    • pp.12-23
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    • 2019
  • This study aims to suggest analysis schemes of urban forests acting as wind ventilation corridor(wind ventilation forest). For this purpose, wind corridor forests were classified into three types: wind-generating forests(WGF), wind-spreading forests (WSF), and wind-connecting forests(WCF), and they were classified into three grades. WGF, WSF and WCF were classified based on the density of forest type map, vegetation index, and ventilation networks, respectively. As a result of analyzing wind corridor forests for Daegu Metropolitan City(883.56㎢), the area of WGF was classified as 443.1㎢ and distributed in the northern and southern regions of Daegu Metropolitan City. Among them, the first grade of WGF occupied the largest area(345.59㎢) and the highest rate(54.44%) in Dalseong-gun. On the other hand, WGF was not found in Jung-gu, because this administrative district is isolated from the forest area. WSF was 32.4㎢, which included representative urban parks of Daegu Metropolitan City, and WSF were found relatively much in Suseong-gu and Dalseong-gun. However, WSF were distributed throughout Metropolitan City, and the vegetation index was not high. The ventilation network that can form WCF included major rivers and roads in Daegu Metropolitan City, but this network was not connected to the urban park from the outer forest. Therefore, it was judged that the formation of WCF connecting WGF outside the city and WSF inside the city would be important. The results of this study can be used as a basic data for systematic wind corridor forest projects, and can be used as basic data for establishing guidelines for wind corridor forest analysis at national and local levels.

Seasonal Variation of Thermal Effluents Dispersion from Kori Nuclear Power Plant Derived from Satellite Data (위성영상을 이용한 고리원자력발전소 온배수 확산의 계절변동)

  • Ahn, Ji-Suk;Kim, Sang-Woo;Park, Myung-Hee;Hwang, Jae-Dong;Lim, Jin-Wook
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.4
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    • pp.52-68
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    • 2014
  • In this study, we investigated the seasonal variation of SST(Sea Surface Temperature) and thermal effluents estimated by using Landsat-7 ETM+ around the Kori Nuclear Power Plant for 10 years(2000~2010). Also, we analyzed the direction and range of thermal effluents dispersion by the tidal current and tide. The results are as follows, First, we figured out the algorithm to estimate SST through the linear regression analysis of Landsat DN(Digital Number) and NOAA SST. And then, the SST was verified by compared with the in situ measurement and NOAA SST. The determination coefficient is 0.97 and root mean square error is $1.05{\sim}1.24^{\circ}C$. Second, the SST distribution of Landsat-7 estimated by linear regression equation showed $12{\sim}13^{\circ}C$ in winter, $13{\sim}19^{\circ}C$ in spring, and $24{\sim}29^{\circ}C$ and $16{\sim}24^{\circ}C$ in summer and fall. The difference of between SST and thermal effluents temperature is $6{\sim}8^{\circ}C$ except for the summer season. The difference of SST is up to $2^{\circ}C$ in August. There is hardly any dispersion of thermal effluents in August. When it comes to the spread range of thermal effluents, the rise range of more than $1^{\circ}C$ in the sea surface temperature showed up to 7.56km from east to west and 8.43km from north to south. The maximum spread area was $11.65km^2$. It is expected that the findings of this study will be used as the foundational data for marine environment monitoring on the area around the nuclear power plant.

An Quantitative Analysis of Severity Classification and Burn Severity for the Large Forest Fire Areas using Normalized Burn Ratio of Landsat Imagery (Landsat 영상으로부터 정규탄화지수 추출과 산불피해지역 및 피해강도의 정량적 분석)

  • Won, Myoung-Soo;Koo, Kyo-Sang;Lee, Myung-Bo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.3
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    • pp.80-92
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    • 2007
  • Forest fire is the dominant large-scale disturbance mechanism in the Korean temperate forest, and it strongly influences forest structure and function. Moreover burn severity incorporates both short- and long-term post-fire effects on the local and regional environment. Burn severity is defined by the degree to which an ecosystem has changed owing to the fire. Vegetation rehabilitation may specifically vary according to burn severity after fire. To understand burn severity and process of vegetation rehabilitation at the damaged area after large-fire is required a lot of man powers and budgets. However the analysis of burn severity in the forest area using satellite imagery can acquire rapidly information and more objective results remotely in the large-fire area. Space and airbone sensors have been used to map area burned, assess characteristics of active fires, and characterize post-fire ecological effects. For classifying fire damaged area and analyzing burn severity of Samcheok fire area occurred in 2000, Cheongyang fire in 2002, and Yangyang fire in 2005 we utilized Normalized Burn Ratio(NBR) technique. The NBR is temporally differenced between pre- and post-fire datasets to determine the extent and degree of change detected from burning. In this paper we use pre- and post-fire imagery from the Landsat TM and ETM+ imagery to compute the NBR and evaluate large-scale patterns of burn severity at 30m spatial resolution. 65% in the Samcheok fire area, 91% in the Cheongyang fire area and 65% in the Yangyang fire area were corresponded to burn severity class above 'High'. Therefore the use of a remotely sensed Differenced Normalized Burn Ratio(${\Delta}NBR$) by RS and GIS allows for the burn severity to be quantified spatially by mapping damaged domain and burn severity across large-fire area.

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