Yogyakarta urban area has grown throughout the year as the course of migration and its attraction to tourists and studentsresulting in the high demand of living space which leads to the increment of the built-up area such as hotels and othersupporting-tourism-activity accommodation, so-called urban sprawl. The increase of paved-surface causes the increase ofland surface temperature (LST), which may impact to micro-climate in the urban area with adverse consequences, forinstance, erratic rainfall and rainstorm in the urban area. Consequently, it triggers new future problems. Therefore, it isnecessary to study LST to perceive the state of temperature change in the study area as a preliminary assessment in studyingurban climate.This paper attempts to present the distribution of Land Surface Temperature (LST) in Yogyakarta urban area, extractedfrom remotely-sensed Landsat 8 image acquired from a two-year image. Before the extraction, several variables areincorporated such as Normalized Difference Vegetation Index (NDVI) to calculate emissivity, as well as atmosphericcorrection parameter transmissivity, upwelling and downwelling radiance. The reflectance values are also corrected toobtain NDVI. Land surface temperature extracted according to the procedures: conversion of the digital number of Landsatimage to radiance, correction of radiance value, conversion of the corrected radiance value to brightness temperature, thenbrightness temperature to land surface temperature. The extracted temperature map then presented into 5oC interval.Consecutively, the two-year of temperature maps are then analyzed to obtain the difference of its spatial distribution. Theexpected result is the expanding high-temperature distribution in the urban area. The result shows there is an increase inthe average land surface temperature by 1,5oC from two different images, 2014 and 2018. The majority value oftemperature is between 30 – 40°C, dominated with the built-up area. Two image shows that the respective area spread from54% to 70%.
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