• Title/Summary/Keyword: Heat Island

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A Study on the Relation of Urban Heat Island and Air Pollution in Seoul Area (서울지역의 도시열섬현상과 대기오염도의 관계에 관한 연구)

  • 장영기;김정욱
    • Journal of Korean Society for Atmospheric Environment
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    • v.7 no.1
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    • pp.49-53
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    • 1991
  • Relations of urban heat island and air pollution are analyzed by using $SO_2$ concentration data (winter season in 1985) from 10 sites of Seoul area and differences of wind speed and air temperature in urban and rural area. Urban heat island is developed when daily mean wind speed at urban site is lower than 1.5m/sec or in the interval of 3.0 $\sim$ 3.5m/sec. When differences between urban and rural air temperature is greater than the overall average of those differences, $SO_2$ concentrations of those above-average differences are 1.3 $\sim$ 1.8 times higher than those of below-average differences. The trends are shown obviously at north-eastern area of Seoul (Gilum Dong, Ssangmun Dong, Myeonmog Dong). When intensity of Urban Heat Island is weak, $SO_2$ concentration was reduced in propotion to a rise of wind speed. But $SO_2$ concentration is on the partial increase in spite of a rise of wind speed when intensity of urban heat island is strong.

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Estimating the Heat Island Development Using Landsat TM and AMeDAS Data

  • Harada, Ippei;M.A., Mohammed Aslam;Kondoh, Akihiko
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.450-452
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    • 2003
  • In the present investigation, an estimation of the growth of heat island development of Tokyo metropolis which accounts nearly 100 sq. km of areal spread has been carried out. Band 6 data of LANDSAT TM (Thematic Mapper) data acquired on August 1984 and 1994 have been used for estimating the expansion of the heat island development. Since the vegetation decrease is usually associated with the heat island development, a ratio of green covering has also been assessed using TM data. In order to establish the relationship with the air temperature, AMeDAS(Automated Meteorological Data Acquisition System) data have been correlated.

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ESTIMATION OF HEAT ISLAND POTENTIAL BASED ON LAND-USE TYPE IN DAEGU

  • Ahn Ji-Suk;Kim Hae-Dong;Kim Sang-Woo
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.394-397
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    • 2005
  • This study aims to estimate a heat island potential distribution based on the land-use types using LANDSAT/TM(1100LST April 2000) and AWS data in Daegu. The heat island potential is defined as a difference between surface temperature and air-temperature at each place. The study area was selected as about $900k km^2$ square including Daegu metropolitan area. Land-use data obtained by dividing all of Daegu metropolitan area into l-km-square three types of maps were prepared, in the 1 960s, 1970s and 2000s respectively. The types of land-use were divided into 5. Forest and farm lands have been reduced at a wide range during 40 years, most of which changed to urban area. The heat island potential distribution presented a striking contrasts according to land-use types. For example, the heat island potential of urban area was higher than $14^{\circ}$ in comparison to those of water or paddy rice areas.

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Estimation of Urban Heat Island Potential Based on Land-Use Type in Summertime of Daegu (대구의 토지이용도 유형에 따른 여름철 도시열섬포텐셜 추정연구)

  • Ahn, Ji-Suk;Kim, Hae-Dong;Kim, Sang-Woo
    • Journal of Environmental Science International
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    • v.16 no.1
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    • pp.65-71
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    • 2007
  • This study aims to estimate a urban heat island potential distribution based on the land-use types using Landsat TM(1100 LST August 2004) and AWS data in Daegu. The heat island potential is defined as a difference between surface temperature and air-temperature at each place. The study area was selected as about $900km^2$ square including Daegu metropolitan area. Land-use data obtained by dividing all of Daegu metropolitan area in- to 1-km-square three types of maps were prepared in the 1960s, 1970s and 2000s respectively. Land-use types were classified into 5 categories. Forest and farm lands have been reduced at a wide range during 40 years. Most of those changed into urban area. The heat island potential distribution presented a striking contrasts according to land-use types. For example, the heat island potential of urban area was higher than $10^{\circ}C$ in comparison to those of water or paddy rice areas.

A Study on the Distribution Characteristic of Urban Surface Temperature and Urban Heat Island Effects (도시 지표면 온도분포 특성 및 열섬완화방안)

  • Do, Hu-Jo;Lee, Jung-Min;Ra, Jung-Hwa
    • Journal of Environmental Science International
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    • v.16 no.5
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    • pp.611-622
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    • 2007
  • The purpose of this research was to three-criteria landuse-pattern, developing density, NDVI which were related to the heat island and find the distribution characteristic of urban surface temperature and urban heat island effects. The results of this study were as follows. According to the analysis of surface temperatures, the first grade was the outside-city like a mountain and its temperature was less than $12.18^{\circ}C$. The fifth grade was the downtown industrial area and its temperature was more than $23.54^{\circ}C$. It means Daegu-Metropolitan-City has the serious heat-island effect. the results of landuse pattern analysis, in case of fifth and forth grade, city area was occupied over 90% with residential, commercial and industrial areas, but in case of third grade, openspace was occupied over 70%. The results of developing density analysis, the temperature had high correlation with building ratio, road ratio, vegetation ratio and etc. To plan for the decrease of heat island effect needed the extension of green space, decrease of paving, but there was a limit to get the objective method for grade classification because of lacking in the basic data, the research of criteria will be accomplished continuously.

The Impact of Urban Heat Island-induced Temperature Differences on the Hatching Rates of Aedes albopictus (도시열섬 현상에 의한 기온차이가 흰줄숲모기(Aedes albopictus) 부화율에 미치는 영향)

  • Jihun Ryu;Kwang Shik Choi
    • Korean journal of applied entomology
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    • v.63 no.1
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    • pp.77-80
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    • 2024
  • Aedes albopictus, a common species in the Republic of Korea, is internationally known as a major vector for various diseases, and it is well-adapted to urban environments. Recent insect outbreaks in urban areas, attributed to climate change and urban heat islands, have increased the necessity of researching the effects on mosquito populations. This study analyzed climate data from 25 Automatic Weather System (AWS) stations in Seoul, identifying urban areas with pronounced heat island effects and suburban areas with milder effects. Nine urban heat island conditions were established based on this analysis, under which the hatching rates of Ae. albopictus were examined. The results revealed an increase in hatching rates correlating with the intensity of the urban heat island effect. Regression analysis further indicated that this trend accelerates as the strength of the heat island effect increases. This study suggests that temperature variations resulting from urban heat island phenomena can significantly influence the hatching rates of Ae. albopictus.

Evaluation of Thermal Environment Improvement Effect from Public Design Improvement Project on the Urban Street Space (도시가로공간의 공공디자인 개선사업에 따른 열환경 개선 효과 평가)

  • Baek, Sang-Hun;Shimizu, Aki;Kim, Hak-Yoon;Jung, Eung-Ho
    • Journal of Environmental Science International
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    • v.20 no.9
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    • pp.1105-1114
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    • 2011
  • In this study, thermal environment improvements throughout public design improvement project on the urban street space were compared and evaluated. Thermo-Render 3.0, 3D-CAD based thermal environment simulation program, had been used for thermal environment improvement evaluations. Followings are the results. First, clayey blocks which have low heat transfer rate and cool island effect by trees and roof gardens brought cooling effects for buildings and surface of streets. Seconds, MRT values showed low levels because of low radiant mulching materials. Thirds, roof gardens contributed to reduce heat island effect since HIP levels were affected by decreasing heat storage effect of buildings from roof gardens. As a result, reducing heat storage effect throughout selecting and arranging proper materials which would not increase heat island potentials should be performed to improve heat island effects.

An Evaluation of the Phenomenon of Heat-Island Effect by Multi-Criteria Methods (다항목 평가기법의 적응을 통한 열섬현상의 평가)

  • Lee Jung-Min;Do Hu-Jo;Ra Jung-Hwa;Kim Soo-Bong;Jung Eung-Ho
    • Journal of Environmental Science International
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    • v.14 no.11
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    • pp.1005-1014
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    • 2005
  • The purpose of this research was to present multi-criteria which were related to the heat island and find methods which decreased heat island affection on the ecological landscape planning. The results of this study were as follows. According to the analysis of surface temperatures, the first grade was the outside-city like a mountain and its temperature was less than $13.0^{\circ}C$. The fifth grade was the downtown, industrial area and its temperature was more than $26.9^{\circ}C$. Therefore, the result was seen the serious heat-island effect. The results of field survey, the closer to the first grade, the higher the value of green coverage. The closer to the fifth grade, the higher the value of impermeability surface, paving materials and colors. According to the correlation analysis, the temperature had high correlation with impermeability surface, paving materials and colors. According to the simple regression analysis, permeability surface, green coverage, topography, impermeability surface, paving materials f: colors, human impact related with surface temperatures. To plan for the decrease of Heat-Island Effect needed the extension of green space, decrease of impermeability surface. This research suggested data for urban green plan and decrease of heat island effect, but there was a limit to get the objective method for grade classification because of lacking in the basic data, the research of multi-criteria will be accomplished continuously.

Evaluation of Thermal Environment in the Detached Housing Area Based on the Form-Based Codes (형태기반코드를 기반으로 한 주거지 열환경 평가)

  • Ryu, Ji-Won;Jung, Eung-Ho
    • Journal of the Korean housing association
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    • v.25 no.5
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    • pp.43-50
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    • 2014
  • This study assesses thermal environment of detached housing area by classifying buildings types with codes based on spatial characteristics and forms of the detached housing area and applying heat island alleviation measures, especially focused on FBCs (Form-Based Codes). We analyzed shapes and materials of outdoor space with 3D-CAD, which can affect the surface temperature of the case studies, focusing on heat island alleviation measures, and performed space design by applying relevant climate factors to a simulation. As to the 3D surface temperature and HIP distribution, low-temperature distribution was shown in the case studies when we applied heat island alleviation measures. FBCs (Form- Based Codes) is being developed for the purpose of creating new urban environment. This study is significant because it pays attention to the effects of surface temperatures on accumulation of sensible heat and reviews heat island alleviation measures with outdoor space shapes/materials in order to lower surface temperatures, aiming at improved pleasantness of the detached housing area.

Influences of Ice Microphysical Processes on Urban Heat Island-Induced Convection and Precipitation (얼음 미시물리 과정이 도시 열섬이 유도하는 대류와 강수에 미치는 영향)

  • Han, Ji-Young;Baik, Jong-Jin
    • Atmosphere
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    • v.17 no.2
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    • pp.195-205
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    • 2007
  • The influences of ice microphysical processes on urban heat island-induced convection and precipitation are numerically investigated using a cloud-resolving model (ARPS). Both warm- and cold-cloud simulations show that the downwind upward motion forced by specified low-level heating, which is regarded as representing an urban heat island, initiates moist convection and results in downwind precipitation. The surface precipitation in the cold-cloud simulation is produced earlier than that in the warm-cloud simulation. The maximum updraft is stronger in the cold-cloud simulation than in the warm-cloud simulation due to the latent heat release by freezing and deposition. The outflow formed in the boundary layer is cooler and propagates faster in the cold-cloud simulation due mainly to the additional cooling by the melting of falling hail particles. The removal of the specified low-level heating after the onset of surface precipitation results in cooler and faster propagating outflow in both the warm- and cold-cloud simulations.