• 한국태양에너지학회 논문집
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• 제32권6호
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• pp.134-140
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• 2012

With rapid modernization and industrialization, many urban areas are becoming overcrowded at a rapid pace and such urban ecological problems as heat island effect are becoming serious due to the reduced green zones resulted from the indiscriminate development. To solve this problem, ecological park, constructed wetlands, and greening on the elevation, balcony, and roof of a building that have the structure and function very close to the state of nature are currently being promoted at the urban or regional level. Especially green roof will be able to not only provide the center of a city with a significant portion of green area but also help to relive heat island effect and improve micro climate by preventing concrete of a building from absorbing heat. According to a recent study, the temperature of green roof in the summer season shows a lower temperature than the outdoor temperature, but inversely the concrete surface shows a higher temperature. Accordingly, this study measured the surface temperature of buildings with green roof in Daejeon area in order to determine how the green roof system would have an impact on the distribution of surface temperature and did a comparative analysis of the distribution of the surface temperature of green roof vs non-green roof based on these theoretical considerations. As a result, it was found that the surface temperature of green roof was lower by $4{\sim}7^{\circ}C$ than that of non-green roof. This is expected to contribute to the mitigation of urban heat island effects.

• 한국대기환경학회지
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• 제28권5호
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• pp.495-505
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• 2012

Modeling the effects of high-rise buildings on thermo-dynamic conditions and meteorological fields over a coastal urban area was conducted using the modified meso-urban meteorological model (Urbanized MM5; uMM5) with the urban canopy parameterization (UCP) and the high-resolution inputs (urban morphology, land-use/land-cover sub-grid distribution, and high-quality digital elevation model data sets). Sensitivity simulations was performed during a typical sea-breeze episode (4~8 August 2006). Comparison between simulations with real urban morphology and changed urban morphology (i.e. high-rise buildings to low residential houses) showed that high-rise buildings could play an important role in urban heat island and land-sea breeze circulation. The major changes in urban meteorologic conditions are followings: significant increase in daytime temperature nearly by $1.0^{\circ}C$ due to sensible heat flux emitted from high density residential houses, decrease in nighttime temperature nearly by $1.0^{\circ}C$ because of the reduction in the storage heat flux emitted from high-rise buildings, and large increase in wind speed (maximum 2 m $s^{-1}$) during the daytime due to lessen drag-force or increased gradient temperature over coastal area.

• 한국지리정보학회지
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• 제8권3호
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• pp.150-160
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• 2005

1991년, 1995년 및 2000년의 NOAA/AVHRR 위성자료와 split-window 방법을 사용하여 한반도 표면온도의 시공간적인 변동을 분석하였다. 한반도 전지역의 낮과 밤의 온도차는 $3{\sim}15^{\circ}C$로 나타났다. 대도시에서 온도차의 계절적 변동과 년별 변동은 교외지역보다 낮게 나타났으며, 도시화의 영향이 분명하게 나타났다. 도시열섬 영향의 특성은 대도시 부산에서 낮과 밤의 온도차를 근거로 알 수 있었다. 또한 북한 및 남한에서 하계 $30^{\circ}C$ 이상 고온을 나타내는 20개 도시 지역을 모니터링 할 수 있었다. 도시환경계획을 위해 본 기술의 사용을 제안한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.717-720
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• 2005

Recently as large sized urban development and the city ward drifting of population are caused, the urban surface temperature is raised very seriously and rapidly. These artificial developments have destroyed the inner and outer landscapes such as topography and have changed complex local climate such as a sudden rise in temperature, the change of wind field and air pollution. In order to clarify this problem visually, the studies on extracting the thermal infrared and the characteristic analysis of local climate in urban area had been performed by using the sixth band of Landsat TM and ETM+. However, there is a need to alternate Landsat TM and ETM+ because these satellite images are not applied any more. Therefore, in this paper it is proposed to use 2 Aster image (2004.4.17 daily 2b03, 2004.10.10 night 2b03) of EOS AM and to extract the surface temperature. Also, the pattern of surface temperature in urban area and the application possibility in local climate study are proposed by verifying the correlation with A WS data. Also, IKONOS image was used to figure out the artificial development area in visual.

• 한국대기환경학회지
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• 제31권2호
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• pp.181-194
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• 2015

Spatial-temporal meteorological features of the Ulsan metropolitan region (UMR) were analyzed using observations and high-resolution numerical modeling. Long-term trend analysis (1970~2013) showed a significant increase of $0.033^{\circ}Cyr^{-1}$ in the 5-year moving average temperature, although detailed short-term features varied, whereas wind speed and relative humidity over the same period displayed clear decreases of $-0.007ms^{-1}$ and $-0.29%yr^{-1}$, respectively. These trends indicate the effects of regional climate change and urbanization in the UMR. Seasonal variations averaged for the most recent three years, 2011~2013, showed that temperatures in three different regions (urban/industrial, suburban, coastal areas) of the UMR had similar seasonality, but significant differences among them were observed for a certain season. Urban and industrial complex regions were characterized by relatively higher temperatures with large differences (max.: $3.6^{\circ}C$) from that in the coastal area in summer. For wind speed, strong values in the range from 3.3 to $3.9ms^{-1}$ occurred in the coastal areas, with large differences clearly shown between the three regions in September and October. Diurnal variations of temperature were characterized by pronounced differences during the daytime (in summer) or nighttime (in winter) between the three regions. Results from the WRF modeling performed for four months of 2012 showed large variations in gridaverage temperature and winds in the UMR, which displayed significant changes by season. Especially, a clear temperature rise in the urban center was identified in July ($0.6^{\circ}C$ higher than nearby urban areas), and overall, relatively weak winds were simulated over urban and inland suburban regions in all seasons.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2003년도 추계학술대회 논문집
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• pp.503-503
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• 2003

Urban heat islands related with Cheongyecheon restoration in Seoul metropolitan area for the summertime of 2003. To investigate the spatial and temporal structure of the urban heat island in Seoul, temperature data measured at 32 automatic weather stations (AWSs) in the Seoul metropolitan area and 12 additional stations operated by the portable device for the measurement of temperature and relative humidity in the Cheonggyecheon area. (omitted)

• 한국조경학회지
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• 제31권3호
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• pp.74-82
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• 2003

Under the assumption that the temperature of one location is closely related to land use characteristics around that location, this study is carried out to assess the impact of urban land use patterns on air temperature. In order to investigate the relationship, GIS techniques and statistical analyses are utilized, after spatially connecting urban land use data in Seoul Metropolitan Area with atmospheric data observed at Automatic Weather Stations (AWS). The research method is as follows: (1) To find out important land use factors on temperature, simple linear regressions for a specific time period (pilot study) are conducted with urban land use characteristics, (2) To make a final model, multiple regressions are carried out with those factors and, (3) To verify that the final model could be appled to explain temperature variations beyond the period, the model is extensively used for 5 different time periods: 1999 as a whole; summer in 1999; 1998 as a whole; summer in 1998; August in 1998. The results of simple linear regression models in the pilot study show that transportation facilities and open space area are very influential on urban air temperature variations, which explain 66 and 61 percent of the variations, respectively. However, the other land use variables (residential, commercial, and mixed land use) are found to have weak or insignificant relationship to the air temperatures. Multiple linear regression with the two important variables in the pilot study is estimated, which shows that the model explains 75 percent of the variability in air temperatures with correct signs of regression coefficients. Thus, it is empirically shown that an increase in open space and a decrease in transportation facilities area can leads to the decrease in air temperature. After the final model is extensively applied to the 5 different time periods, the estimated models explain 68 ∼ 75 percent of the variations in the temperatures is significant regression coefficients for all explanatory variables. This result provides a possibility that one air temperature model for a specific time period could be a good model for other time periods near to the period. The important implications of this result to lessen high air temperature we: (1) to expand and to conserve open space and (2) to control transportation-related factors such as transportation facilities area, road pavement and traffic congestion.

• 환경영향평가
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• 제17권6호
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• pp.357-366
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• 2008

It is certain that urbanization has transformed the ecological consequences severely, but urban ecosystem is not fully understood yet. Urban growth is not like a static form and it spreads spatially and temporally. Therefore in studying urban ecosystem, it is important to relate the spatial pattern of urbanization to ecological processes. Using gradient analysis, we attempted to quantify the urbanization's spatial impacts in Daejeon-city and Cheonan-city, Chungcheong-province, Korea. Because of Multifunctional Administrative City Planning (MACP), a lot of development projects are planned in Chungcheong-province, Korea. It's important to study about original cities' patterns and impacts. These results can be adopted to future city planning. So several measures such as fragmentation, vegetation index, surface temperature, population density, and income rate were computed along a 75km long and 3km wide transect. The results showed that Daejeon-city has a wider urban center, lower vegetation indexes, and higher surface temperature than Cheonan-city. Therefore in the perspective of urban environments and sustainable urbanism, it seems that Cheonan-city is better than Daejeon-city. The changes along the transect have important ecological implications, and quantifying the urbanization gradient is an important step in understanding urban ecology.

• 대한원격탐사학회지
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• 제38권1호
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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.

• International Journal of Advanced Culture Technology
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• 제12권2호
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• pp.353-359
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• 2024

The color temperature and light color of nighttime lighting in a particular city is an important factor in determining its nighttime identity. To quantitatively analyze the nocturnal characteristics of Seoul, this study focuses on the light color of the lighting sources that used in the places included in the Seoul Night View 100 Photobook. As a result, the color temperature of white light in the surveyed places is in the range of 2,500~3,500K, of which 3,000~3,500K represents the highest proportion. In addition, the color temperature in the 2,500~3,500K range was found to be evenly distributed across the five surveyed regions. Apart from white light, blue color hue accounts for a high percentage in the monochromic light category, and the excitation purity was measured to be 71.6% on average. In addition, 46% of the buildings with monochromic light are in urban centers.