• 대한원격탐사학회지
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• 제37권6_3호
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• pp.1975-1984
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• 2021

도시 확장은 도시의 온도를 상승시키고, 이러한 도시의 온도 상승은 사회적, 경제적, 신체적 피해를 초래한다. 이러한 도시열섬을 예방하고 도시의 지표면 온도를 감소시키기 위해서는 도시 공간을 구성하는 지형지물들의 냉각 효과를 계량화하는 것이 중요하다. 이에 본 연구에서는 서울을 대상으로 토지피복 각각의 객체들과 지표면 온도와의 관계를 파악하고자 토지피복지도 6개 클래스로 분류하여 지표면 온도와 객체들의 면적, 둘레/면적, 정규식생지수와의 상관분석과 다중회귀분석을 수행했다. 분석 결과 정규식생지수는 지표면 온도와 상관성이 높게 나타났다. 그리고 다중회귀분석에서도 지표면 온도 예측에 정규식생지수가 다른 계수보다 높은 영향력을 행사했다. 다만 다중회귀분석 결과 도출된 모델들의 설명력은 낮게 나타났는데, 향후 아리랑 3A의 고해상 중적외선 데이터를 연계 활용하여 지속적인 모니터링을 수행한다면 모델의 설명력을 한층 강화할 수 있을 것이다. 그리고 녹지공간의 식생 활력까지 고려한 토지피복 유형과 도시 공간 내 지표면 온도와의 관계를 기반으로 도시계획에 활용한다면 도시의 지표면 온도를 저감하는데 큰 도움이 될 수 있을 것으로 판단된다.

• 한국지리정보학회지
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• 제8권2호
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• pp.21-30
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• 2005

본 연구는 도시지역에서 지표용도를 결정하는 요인으로서 토지이용과 식생분포를 설정하고 이들의 상호관계를 규명하는 것을 목적으로 한다. 이를 위하여 대구광역시를 사례지역으로 위성영상을 판독하고 그 결과를 수치지도와 중첩하여 분석을 실시하였다. 지표온도와 식생지수(표준식생지수)는 위성영상분석을 통하여 도출하였고 토지이용자료는 통계청이 지난 2001년 제작한 기초단위구 자료를 통하여 획득하였다. 분석결과 예상한 바와 같이 지표온도는 식생분포와 토지이용분포와 깊은 상관관계가 있는 가운데 식생상태보다는 토지이용에 의해 더욱 많은 영향을 받는 것으로 나타났다. 이에 따라 본 연구는 토지이용과 지표온도와의 관계규명에 초점을 두었다. 이를 위하여 본 연구는 18개로 구분된 토지이용을 표면온도에 따라 Duncan 검증방법으로 7-8개의 그룹으로 분류하였다. 이에 의하면 지표온도는 제조업과 관련된 토지이용이 많은 지역에서 가장 높았고, 그 뒤를 이어 도심상업지역이 높았다. 반면 농업 및 임야지역의 지표온도가 가장 낮게 나타났다.

• 한국농공학회논문집
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• 제50권3호
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• pp.115-123
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• 2008

Evapotranspiration mapping using both meteorological ground-based measurements and satellite-derived information has been widely studied during the last few decades and various methods have been developed for this purpose. It is significant and necessary to estimate regional evapotranspiration (ET) distribution in the hydrology and water resource research. The study focused on analyzing the surface ET of Chungbuk region using Landsat 7 ETM imagery. For this process, we estimated the regional daily evapotranspiration on May 8, 2000. The estimation of surface evapotranspiration is based on the relationship between Temperature Vegetation Dryness Index (TVDI) and Morton's actual ET. TVDI is the relational expression between Normalized Difference of Vegetation Index (NDVI) and Land Surface Temperature (LST). The distribution of NDVI corresponds well with that of land-use/land cover in Chungbuk. The LST of several part of city in Chungbuk region is higher in comparison with the averaged LST. And TVDI corresponds too well with that of land cover/land use in Chungbuk region. The low evapotranspiration availability is distinguished over the large city like Cheongju-si, Chungju-si and the difference of evapotranspiration availability on forest and paddy is high.

• 환경영향평가
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• 제19권4호
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• pp.397-407
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• 2010

The increase of the solar reradiation from urban areas relative to suburban due to urbanization heats up the air temperature in urban areas and this is called the urban heat island (UHI) effect. This UHI effect has a positive relationship with the degree of urbanization. Through the studies on UHI using the satellite imagery, the effect of the surface heat radiation was observed by verifying the relationship between the air temperature and the land cover types (surface materials such as urban, vegetation, etc.). In this study, however, the surface temperature distribution was studied in terms of land use types for Seoul. Using land use types, the surface temperature in urban areas such as residential, industrial, and commercial areas in Yeongdeungpo, highly packed with industrial and residential buildings, was maximum $6^{\circ}C$ higher than in the bare ground, which indicated that the surface temperature reflected the pattern of the human-consumed energy on the areas and showed that one of the important causes influencing the air temperature except the surface heat reradiation by the sun is the anthropogenic heat. Also, the effect due to the restoration of the Chunggae stream on UHI was investigated. The average surface temperature for the Chunggae stream was reduced about $0.4^{\circ}C$ after restoration. Considering that each satellite image pixel includes mixture of several materials such as concrete and asphalt, the average surface temperature might be much lower locally reducing UHI near the stream.

• 대한원격탐사학회지
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• 제39권1호
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• pp.99-110
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• 2023

Land surface temperature (LST) is a critical environmental indicator affected by land cover (LC) changes. Currently, the most convenient and fastest way to retrieve LST is to use remote sensing images due to their continuous monitoring of the Earth's surface. The work intended to investigate land cover change and temperature response inAn-Najaf province. Landsat multispectral imageries acquired inAugust 1989, 2004, and 2021 were employed to estimate land cover change and LST responses. The findings exhibited an increase in water bodies, built-up areas, plantations, and croplands by 7.78%, 7.27%, 6.98%, 3.24%, and 7.78%, respectively, while bare soil decreased by 25.27% for the period (1989-2021). This indicates a transition from barren lands to different land cover types. The contribution index (CI) was employed to depict how changes in land cover categories altered mean region surface temperatures. The highest LSTs recorded were in bare lands (42.2℃, 44.25℃, and 46.9℃), followed by built-up zones (41.6℃, 43.96℃, and 44.89℃), cropland (30.9℃, 32.96℃, and 34.76℃), plantations (35.4℃, 36.97℃, and 38.92℃), and water bodies (27.3℃, 29.35℃, and 29.68℃) respectively, in 1989, 2004, and 2021. Consequently, these changes resulted in significant variances in LST between different LC types.

• Advances in environmental research
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• 제6권4호
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• pp.265-279
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• 2017

The climate change has made adverse effects on land surface temperature for many regions of the world. Several climatic studies focused on different downscaling techniques for climatological parameters of different regions. For statistical downscaling of any hydrological parameters, conventional Neural Network Models were used in common. However, it seems that in any modeling study, uncertainty is a vital aspect when making any predictions about the performance. In this paper, Gamma Test is performed to determine the data length selection for training to minimize the uncertainty in model development. Another measure to improve the data quality and model development are wavelet transforms. Hence, Gamma Test with Wavelet decomposed Feedforward Neural Network (GT-WNN) model is developed and tested for downscaled land surface temperature of Patna Urban, Bihar. The results of GT-WNN model are compared with GT-FFNN and conventional Feedforward Neural Network (FFNN) model. The effectiveness of the developed models is illustrated by Root Mean Square Error and Coefficient of Correlation. Results showed that GT-WNN outperformed the GT-FFNN and conventional FFNN in downscaling the land surface temperature. The land surface temperature is forecasted for a period of 2015-2044 with GT-WNN model for Patna Urban in Bihar. In addition, the significance of the probable changes in the land surface temperature is also found through Mann-Kendall (M-K) Test for Summer, Winter, Monsoon and Post Monsoon seasons. Results showed an increasing surface temperature trend for summer and winter seasons and no significant trend for monsoon and post monsoon season over the study area for the period between 2015 and 2044. Overall, the M-K test analysis for the annual data shows an increasing trend in the land surface temperature of Patna Urban.

• 대한공간정보학회지
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• 제13권4호
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• pp.59-65
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• 2005

효율적인 국토관리를 위해서 과거로부터의 토지피복/토지이용 변화를 탐지하고 미래의 도시계획에 반영하는 것은 매우 중요하다고 할 수 있다. 본 연구에서는 시계열 Landsat 영상을 이용하여 토지피복/토지이용 분류를 수행함으로써 도시변화를 분석하고 도시화에 따른 지표온도의 변화를 조사하였다. 해상도 30m의 Landsat 영상에서 도시변화 후보지역을 추출하고 자세한 변화 상황을 고찰하기 위해 고해상도 항공사진을 함께 사용하는 계층적 변화탐지기법을 사용하였다. 또한, 도시의 발달과 지표온도의 상관성을 평가하기 위하여 Landsat 영상의 열적외선 파장영역을 이용하여 온도를 계산하여 실제기온과 비교하고 토지피복별 지표온도를 계산하였다. 연구 결과 도심지의 팽창을 수치적으로 확인 할 수 있었고 도시화로 인한 온도 상승을 탐지할 수 있었다.

• 대한원격탐사학회지
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• 제35권4호
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• pp.609-616
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• 2019

Land surface temperature ($T_s$) is a critical variable for understanding the surface energy exchange between land and atmosphere. Using the data measured from micrometeorological flux towers, three types of $T_s$, obtained using a thermal-infrared radiometer (IRT), a net radiometer, and an equation for sensible heat flux, were compared. The $T_s$ estimated using the net radiometer was highly correlated with the $T_s$ obtained from the IRT. Both values acceptably fit the $T_s$ from the Terra/MODIS (Moderate Resolution Imaging Spectroradiometer)satellite. These results will enhance the measurement of land surface temperatures at various scales. Further, they are useful for understanding land surface energy partitioning to evaluate and develop land surface models and algorithms for satellite remote sensing products associated with surface thermal conditions.

• 한국측량학회지
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• 제35권4호
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• pp.313-318
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• 2017

Land surface temperature is essential for monitoring abnormal climate phenomena such as UHI (Urban Heat Islands), and for modeling weather patterns. However, the quality of surface temperature obtained from the optical space imagery is affected by many factors such as, revisit period of the satellite, instance of capture, spatial resolution, and cloud coverage. Landsat 8 imagery, often used to obtain surface temperatures, has a high resolution of 30 meters (100 meters rearranged to 30 meters) and a revisit frequency of 16 days. On the contrary, MODIS imagery can be acquired daily with a spatial resolution of about 1 kilometer. Many past attempts have been made using both Landsat and MODIS imagery to complement each other to produce an imagery of improved temporal and spatial resolution. This paper applied machine learning methods and performed downscaling which can obtain daily based land surface temperature imagery of 30 meters.

• 환경영향평가
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• 제22권1호
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• pp.19-26
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• 2013

The propose of this study is to analyze the optimum spatial resolution of the urban spatial thermal environment structure and to evaluate of the possibility detection using aerial photographs and thermal satellite images. The proper techniques of the optimum spatial resolution for the urban spatial thermal environment structure were analyzed. Thermal infrared satellite image of Seoul city were used for the change rate of surface temperature variation and suggested to the spatial extent and effects of urban surface characteristics and spatial data was interpreted as regions. To extract the surface temperature, Landsat thermal infrared satellite image compared with an automatic weather station data and in the field of the measured temperature and surface temperature by thermal environment affects, the spatial domain has been verified. The surface temperature of the satellite images to extract after adjusting surface temperature isotherms were constructed. The changes in surface temperature from 2008 to 2012 the average surface temperature observation images of changing areas were divided into space. The results of this study are as follows: Through analysis of satellite imagery, Seoul city surface temperature change due to extraction comfort indices were classified into four grades. The comfort index indicative of the temperature of Gangnam-gu, $23.7{\sim}27.2(^{\circ}C)$ range and Songpagu, a $22.7{\sim}30.6(^{\circ}C)$ respectively, the surface temperature of Yeouido $25.8{\sim}32.6(^{\circ}C)$ were in the range.