• Title/Summary/Keyword: Heat Island Effect

Search Result 210, Processing Time 0.022 seconds

An Econometric Analysis of Mitigating Urban Heat Island Effect with Urban Forest (계량경제적 접근을 통한 도시림의 도시열섬 완화효과 분석)

  • Kim, Dong-Hyeon;Kim, Eui-Gyeong;Yang, Jun-Seok;Kim, Hyeon-Geun;Shin, Hae-Jin
    • Journal of Korean Society of Forest Science
    • /
    • v.100 no.1
    • /
    • pp.79-87
    • /
    • 2011
  • This study was conducted to identify the relationship between urban heat island effect and forest, analyzing electricity consumption model and temperature change model. Electricity consumption model was adopted to clarify a role of forests in alleviating the heat island effect at the national scale, while temperature change model was adopted to clarify a role of forests in mitigating urban heat island effect on metropolis with using econometric analysis. The analysis results from both models clearly show a negative correlation between the urban forests within living areas and heat island effect. In particular, when urban forests within living area per person increases by $1m^2$, the average municipal electricity consumption decreases by 0.02MWh and the summer daytime temperature for metropolitan cities decreases by $1.15^{\circ}C$.

An Analysis of Thermal Environment Change according to Green Roof System (옥상녹화 조성에 따른 열환경 변화분석)

  • Park, Ji-Young;Jung, Eung-Ho;Kim, Dae-Wuk;Cha, Jae-Gyu;Shimizu, Aki
    • Proceeding of Spring/Autumn Annual Conference of KHA
    • /
    • 2009.11a
    • /
    • pp.100-103
    • /
    • 2009
  • The impermeable area on the surface of city has been increased as buildings and artificial landcover have continually been increased. Urban development has gradually decreased the green zone in downtown and alienated the city from the natural environment on outskirt area devastating the natural eco system. There arise the environmental problems peculiar to city including urban heat island phenomenon, urban flood, air pollution and urban desertification. As one of urban plans to solve such problems, green roof system is attracting attentions. The purpose of this study was to investigate the heat reduction effect according to the development of green roof system and to quantify the heat reduction effect by analyzing through simulation the heat environment before and after green roof system. For thermal environment analysis, Thermo-Render 3.0 was used that was developed by Tokyo Industrial College to simulate. The simulation showed that the heat island index before and after the development of tree-planting on rooftop changed maximum $0.86^{\circ}C$ and the surface temperature changed about $20^{\circ}C$. Only with lawn planting, heat reduction effect was great and it means that the green roof system in low-management-light-weight type is enough to see effect. The simulation identified that only lawn planting for green rooftop brought such difference and could lower the heat island index at a narrow area. It is judged that application of green roof system to wider areas might relieve urban heat island phenomenon positively.

  • PDF

Analysis of the Correlation between Urban High Temperature Phenomenon and Air Pollution during Summer in Daegu

  • An, Eun-Ji;Kim, Hae-Dong
    • Journal of Environmental Science International
    • /
    • v.28 no.10
    • /
    • pp.831-840
    • /
    • 2019
  • Recently, summer high temperature events caused by climate change and urban heat island phenomenon have become a serious social problem around the world. Urban areas have low albedo and huge heat storage, resulting in higher temperatures and longer lasting characteristics. To effectively consider the urban heat island measures, it is important to quantitatively grasp the impact of urban high temperatures on the society. Until now, the study of urban heat island phenomenon had been carried out focusing only on the effects of urban high temperature on human health (such as heat stroke and sleep disturbance). In this study, we focus on the effect of urban heat island phenomenon on air pollution. In particular, the relationship between high temperature phenomena in urban areas during summer and the concentration of photochemical oxidant is investigated. High concentrations of ozone during summer are confirmed to coincide with a day when the causative substances (NO2,VOCs) are high in urban areas during the early morning hours. Further, it is noted that the night urban heat island intensity is large.. Finally, although the concentration of other air pollutants has been decreasing in the long term, the concentration of photochemical oxidant gradually increases in Daegu.

A Study on Quantitative Estimation for prevention of Heat Island by Using New & Renewable Energy (신재생에너지 적용이 도시열섬방지에 미치는 기여도 분석)

  • Son, Won-Tug;Park, Jung-Han;Park, Kyung-Soon
    • Proceedings of the SAREK Conference
    • /
    • 2009.06a
    • /
    • pp.508-513
    • /
    • 2009
  • Significant air temperature increases in urban areas are known as the heat island phenomenon in a global scale. Therefore, we use numerical model in order to analyze quantitative effects by using new & renewable energy on the heat island phenomenon in urban area. The present study quantitatively analyzes the Urban Heat Island Effects, Energy-Saving Effects, and Environmental Load Decrease Effect along New and Renewable Energy Application which is 10% of the Building Energy Consumption.

  • PDF

A Study on the Effects of prevention of the Urban Heat Island by Using New & Renewable Energy (신재생에너지 사용이 도시열섬방지에 미치는 영향에 대한 연구)

  • Son, Won-Tug;Choi, Young-Sik
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.12 no.3
    • /
    • pp.157-162
    • /
    • 2009
  • Significant air temperature increases in urban areas are known as the heat island phenomenon in a global scale. Therefore, we use numerical model in order to analyze quantitative effects by using new & renewable energy on the heat island phenomenon in urban area. The present study quantitatively analyzes the Urban Heat Island Effects, Energy-Saving Effects, and Environmental Load Decrease Effect along New and Renewable Energy Application which is 10% of the Building Energy Consumption.

  • PDF

A Numerical Simulation of Heat Flow Field for Heat Island Effect Analysis to Air Pollutants Dispersion in Apartment Complex (아파트 단지내의 열섬효과가 대기오염물질 확산에 미치는 영향 해석을 위한 열유동장 수치모의)

  • Jang Eun-Suk
    • Journal of Environmental Science International
    • /
    • v.14 no.6
    • /
    • pp.577-582
    • /
    • 2005
  • Enormous apartment complexes in urban areas, temporary inversion state and heat island effect occur due to the strong sunshine and weak wind speeds which hinders the dispersion of air pollutants that are emitted from neighboring areas of apartment complexes. In this study, analysis were conducted by using the Fluent code based on the CFD(Computation Fluid Dynamics), including building layout, material, building height from the ground surface, the heat, analysis of flow field in the apartment complex. It was estimated that the temporal radiation inversion phenomenon during the daytime, which was caused by the weak wind speed and higher temperatures in the upper level, contributed to the stagnation of the air pollutants in the lower layer of the apartment complex.

Mapping and Analyzing the Park Cooling Intensity in Mitigation of Urban Heat Island Effect in Lahore, Pakistan

  • Hanif, Aysha;Nasar-u-Minallah, Muhammad;Zia, Sahar;Ashraf, Iqra
    • Korean Journal of Remote Sensing
    • /
    • v.38 no.1
    • /
    • pp.127-137
    • /
    • 2022
  • Urban Heat Island (UHI) effect has been widely studied as a global concern of the 21st century. Heat generation from urban built-up structures and anthropogenic heat sources are the main factors to create UHIs. Unfortunately, both factors are expanding rapidly in Lahore and accelerating UHI effects. The effects of UHI are expanding with the expansion of impermeable surfaces towards urban green areas. Therefore, this study was arranged to analyze the role of urban cooling intensity in reducing urban heat island effects. For this purpose, 15 parks were selected to analyze their effects on the land surface temperature (LST) of Lahore. The study obtained two images of Landsat-8 based on seasons: the first of June-2018 for summer and the second of November-2018 for winter. The LST of the study area was calculated using the radiative transfer equation (RTE) method. The results show that the theme parks have the largest cooling effect while the linear parks have the lowest. The mean park LST and PCI of the samples are also positively correlated with the fractional vegetation cover (FVC) and normalized difference water index (NDWI). So, it is concluded that urban parks play a positive role in reducing and mitigating LST and UHI effects. Therefore, it is suggested that the increase of vegetation cover should be used to develop impervious surfaces and sustainable landscape planning.

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
    • /
    • v.63 no.1
    • /
    • pp.77-80
    • /
    • 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.

Green-infra Strategies for Mitigating Urban Heat Island (도시열섬현상완화를 위한 그린인프라 전략)

  • Park, Chae-Yeon;Lee, Dong-Kun;Kwon, Eu-gene;Her, Min-ju
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.20 no.5
    • /
    • pp.67-81
    • /
    • 2017
  • Because of lack of accurate understanding of the mechanism of urban heat island (UHI) phenomenon and lack of scientific discussion, it is hard to come up with effective measures to mitigate UHI phenomenon. This study systematically described the UHI and suggested the solutions using green-infrastructure (green-infra). The factors that control UHI are very diverse: radiant heat flux, latent heat flux, storage heat flux, and artificial heat flux, and the air temperature is formed by the combination effect of radiation, conduction and convection. Green-infra strategies can improve thermal environment by reducing radiant heat flux (the albedo effect, the shade effect), increasing latent heat flux (the evapotranspiration effect), and creating a wind path (cooling air flow). As a result of measurement, green-infra could reduce radiant heat flux as $270W/m^2$ due to shadow effect and produce $170W/m^2$ latent heat flux due to evaporation. Finally, green-infra can be applied differently on the macro(urban) scale and micro scale, therefore, we should plan and design green-infra after the target objects of structures are set.

Comparison of Land Surface Temperatures Derived from Surface Emissivity with Urban Heat Island Effect (지표 방사율에 의한 지표온도와 도시열섬효과 비교)

  • Jeong, Jong-Chul
    • Journal of Environmental Impact Assessment
    • /
    • v.18 no.4
    • /
    • pp.219-227
    • /
    • 2009
  • Because of urban development and changed land cover types, It is very important to acquire pixel unit of land surface temperature(LST) information when the heat island effect(HIE) of regional area are investigated. The brightness temperature observed by satellite is very useful for assessing the pixel unit of LST distributions for the analysis of thermal environment problems of urban areas. Also, satellite land cover data are very useful to our understanding of surface conditions of study areas. In this study, brightness temperature information of Landsat TM thermal channel was analyzed and compared with land cover information of Jeon-ju city. The atmospheric correction of TM thermal channel carried out to explain for compared LST long term monitoring errors. However, simple estimation and evaluation methods to find a physical relationship between LST from satellite images and in-situ data are compared with reference channel emissivity.