• Korean Journal of Remote Sensing
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• v.38 no.1
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• pp.127-137
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• 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.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.508-513
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• 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.

• 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.

• 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.

• 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.

• KIEAE Journal
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• v.11 no.5
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• pp.13-18
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• 2011

The overall aim of this study is to mitigate urban environmental problems. In particular, to reduce the effects of urban heat island phenomenon which is one of the urban planning perspective. This study focused on the analysis of the relationship between the urban heat island effect and the thermal and wind properties. To do this analysis, water space was virtually made at Yeol_Mae village Apt. Because it is very difficult to set up water space for the existing apartment complexes due to realistic constraints. This study, therefore has a strong sort of guidelines to create water space for newly formed city. It was based on the concept of virtual city through an in-depth analysis on reduction of urban heat island effects for the existing apartment along with creation of water space. To analysis site, Envi-Met Model developed by Michael Bruse was used. The results are as follows. The temperature went from 298.9K to 297.82K and The wind speed went from 1.42m/s to 1.43m/s. The results are slight in this study because creation of water space is planned to a small area of an apartment complex. But if the water space would be applied to a whole city, the mitigation effect of urban heat island would be bigger.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.4
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• pp.303-309
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• 1993

An observational study of urban heat island was carried out using field data obatined during 6 days in May and August 1992 in Chunchon(population size 180.000). Air temperature was measured at 64 points along two sampling ruoutes by themisters attached to cars. Both routes cover urban and rural area and across the cneter of urban area. Continuous observation of air sonde was perfomed to clarify heights of nocturnal boundary layer(NBL) at the center of urban area. Surface meteorological observations were performed at both urban and rural sites. This study showed that heat island phenomena was obviously observed at the urbanized area during the night time with low wind speed. The average NBL heights exteded to about 10 meters, but varied with meteorological conditions. After sunset, the air temperature decreased with time at both sites and cooling rate at the urban site was greater than the rural site. The maximum heat island intensity was 7.5$^{\circ}$C at 21 LST, May 4. Usingthe two meteorological data sets obtained from urban and rural sites, the air pollutant concentration was calculated by Gaussian plume model which can obtain not only horizontal distribution of concentration but also vertical distribution. The result indicated that the concentration resulted from urban meteorological data set was lower than that from rural meteorological data set. It was also calculated that the air pollutant extended to higher level in urban meteorological data set than that in rural meteorological data set.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.79-87
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• 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 $1.15^{\circ}C$.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.3
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• pp.1-16
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• 2022

Areas developed through land reclamation projects have huge economic advantages in terms of supplying lands that can be used for farmlands, urban areas and etc., however have relatively small areas of grasslands and densely located buildings compared to inland cities. Hence, an urban heat island is occurring in these areas due to this characteristic, and in particular, the urban heat island in Cheongna International City is getting serious. In this study, the urban heat island in Cheongna International City was evaluated and analyzed by classified into the three periods after the reclamation project: farmland(2001-2008), development(2009-2013) and artificial grassland(2014-2020). The land cover map and Landsat time-series imagery were utilized for measuring the differences of the land surface temperatures between the urbanized areas and the grassland/forest areas in Cheongna International City. The statistical results showed that the differences in the land surface temperature between these areas were calculated to be at most 0℃ during the period of farmland, at most 3.60℃ during the period of development, and at most 2.51℃ during the period of grassland. This study proved that the urban heat island phenomenon increased when the urbanized areas increased, and the urban heat island phenomenon decreased when the artificial grassland areas increased in Cheongna International City where the reclamation project was carried out. The statistical results derived through this research can be used as the reference data for identifying the urban heat island problem in urban planning and establishing the reduction plan.

• Journal of Environmental Science International
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• v.11 no.10
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• pp.1045-1054
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• 2002

Urban atmospheric conditions are usually settled as warmer, drier and dirtier than those of rural counterpart owing to reduction of green space and water space area heat retention in surfaces such as concrete and asphalt, and abundant fuel consumption. The characteristics of urban climate has become generally known as urban heat island. The purpose of this study is to investigate the temporal and spatial distribution of the heat emission from human activity, which is a main factor causing urban heat island. In this study, the anthropogenic heat fluxes emitted from vehicles and constructions are estimated by computational grid mesh which is divided by 1km $\times$ 1km. The anthropogenic heat flux by grid mesh can be applied to a numerical simulation model of the local circulation model. The constructions are classified into 9 energy-consumption types - hospital, hotel, office, department store, commercial store, school, factory, detached house and flat. The vehicles classified into 4 energy-consumption types - car, taxi, truck and bus. The seasonal mean of anthropogenic heat flux around central Daegu exceeded $50 W/m^2$ in winter. The annual mean anthropogenic heat flux exceeded $20 W/m^2$. The values are nearly equivalent to the anthropogenic heat flux in the suburbs of Tokyo, Japan.