Evaluation of surface temperature in relation to land use/cover using remote sensing data

Subject Areas : Geospatial systems development

Behrouz Ahmadi ¹ , Ardavan Ghorbani ^{2 *} , Taher Safarrad ³ , Behrouz Sobhani ⁴

1 - MSc. Student of Remote sensing and Geographic Information System, University of Mohaghegh Ardabili, Iran
2 - Assoc. Prof. University of Mohaghegh Ardabili, Iran
3 - PhD. Students of Climatology, University of Tehran, Iran
4 - Assoc. Prof. University of Mohaghegh Ardabili, Iran

Received: 2014-05-29 Accepted : 2015-01-01 Published : 2015-05-22

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Abstract :

This study aimed to evaluate land surface temperature in relation to vegetation and urban land use using remote sensing data within the city of Ardabil and urban margin of up to 15km radius, using 2010 Landsat TM image, after preprocessing, such as data preparation, radiometric and geometric correction, which was performed using ENVI®4.7 software. Then for measuring the surface temperature, the thermal band of an image using relevant equations for converting digital numbers to radiance and radiance to brightness temperature was used. In the next step for calculating emissivity the Normalized Difference Vegetation Index (NDVI) index was used and finally land use map in six classes using supervised classification method were extracted from the image. For extracting the vegetation fraction the Dimidiate model was used. To assess the accuracy of surface temperature extracted from the image, hourly data from 4 weather stations was used and to reconcile these data with each other, a simple regression equation was used. Results show that the coefficient of relationship between land surface temperature (derived from the image) and air temperature recorded at the stations was 0.79 and the correlation between recorded air temperature of stations and derived air temperature from the image was obtained 0.99.