Abstract:
Nakhon Ratchasima is one of the main cities in the northeastern part of Thailand. The city has several advantages in terms of location and historical background. Thailands government policy also supports the city to become a central place in the region. As a result, urbanization quickly became a major cause for the loss of green areas. An increased surface temperature is also a factor contributing to global warming. This research used remote sensing technology to study the urban expansion of the city and adopted the split window method to assess its surface temperature. The urbans land use change in 2026 was also predicted using CA-Markov model in two situations and discussed the relationships between land use and the land surface temperature of Nakhon Ratchasima city. This study aimed to provide recommendations for future policy to prevent unplanned urbanization in the area. The policy proposed regarded the reduction of green area and an increased surface temperature of the city in the future.The data regarding urbanization was collected in three periods: Landsat-5 (1992), Landsat-7 (2002) and THEOS (2016). The land surface temperature (LST) was studied using satellite images from Landsat-5 (1992), Landsat-7 (2002) and Landsat-8 (2016). The results showed that the urban expanded steadily (1.93 percent per year) while the green areas shrunk steadily (1.78 percent per year), especially agricultural area in the north. This was consistent with the results from previous studies on land surface temperature showing its rising trend (0.53 percent per year), especially in high-rise buildings, shopping malls and condominium residences. The results of the relationship between land use and LST revealed a direct statistical relationship between built-up areas and LST. However, the relationship between green areas and LST showed an inverse variable. The 2026 land use prediction revealed that in Situation 1, based on past trends, the urbans expansion in built-up areas increased by 2.13 percent per year, while the green areas decreased by 4.38 percent per year. However, Situations 2, observed planned urbanization in specific area and adopted policy development plans, the expansion in built-up area increased by 0.5 percent per year, while the green areas decreased by 2.41 percent per year. The results indicated that planning the urbanization according to the policies development plans, especially in specific areas, contributed to a more efficient urbanization growth. Therefore, the development of Nakhon Ratchasima city, in order to fix and prevent environmental problems from urbanization, should rely heavily on policy to control and limit aimless urbanization. The city should provide designated open space and promote the use of Floor Area Ratio (FAR) and Open Space Ratio (OSR) with urban planning measures as well as increasing the green areas.