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Rapid urbanization has a great impact on city temperature, which causes urban heat island (UHI) and affecting quality of local people. This study attempts to detect changes in landuse and land surface temperature (LST) over Mueang Chiang Mai District, Thailand. Multi-temporal Landsat TM and ETM+ satellite images acquired in April in 1994, 2004 and 2014 were selected to analyze changes in land-use, land surface temperature (LST) and UHI using object based image analysis method and thermal image processing. Overall accuracy of classification results were computed higher than 84.21% for all Landsat images. Results show that during the 20-years of the study period, the city experienced a huge land-use changed. Maximum LST values were detected for bareland class in each study year while minimum LST values were detected for forest, agriculture, and water resource classes. The difference of temperature between city and suburb areas was range from 1 - 2 °C in 1994 and rapidly increased to 5-8 &@#176;C in 2014, which related to the land-use changes and UHI situation in the study area. The results are benefit to the local government for better understanding and monitoring situation of UHI phenomenon. [ABSTRACT FROM AUTHOR]

Thermal anomaly is one of the earthquake precursor in earthquake preparatory phase. Remote sensing in thermal region has been employed recently based on the concept of stress accumulation in the active plate tectonics region, which may be transformed as temperature variation prior event. MODIS Land Surface Temperature (LST) has been commonly used to locate thermal anomalies before earthquake. Recently research has been focusing on moderate or large magnitude earthquake events. In Thailand, even though small earthquake (< 5M) can be affected unprepared area. This study, daily day and night time of MODIS MOD11A1 product for 15 days before and after the Phan M4.4 earthquake on 17th November 2006 were processed and analyzed to locate possibility of thermal anomalies. Average LST before and after events were used for removing background temperature in the area and comparative method was used to detect thermal anomalies. The result found maximum temperature after removed background temperature was 5.36 °C which occurred 3-5 days prior the quake. Therefore, it may have concluded that small earthquake may release energy which can be detected as thermal anomaly. Nevertheless, thermal precursors should be discovered to understand mechanism of earthquake precursor further. [ABSTRACT FROM AUTHOR]