IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 _______________________________________________________________________________________ Volume: 05 Issue: 03 | Mar-2016, Available @ http://www.ijret.org 457 USING LANDSAT-8 DATA TO EXPLORE THE CORRELATION BETWEEN URBAN HEAT ISLAND AND URBAN LAND USES Rayan H. Alhawiti 1 , Diana Mitsova 2 1,2 School of Urban and Regional Planning, Florida Atlantic University, Boca Raton, Florida, USA. Abstract On a local scale, climate change can potentially exacerbate the urban heat island (UHI) effect characterized by an abrupt thermal gradient between urbanized and nearby non-urbanized areas. While it is well-known that the presence of impervious surfaces and less vegetation influence urban microclimate, relatively little attention has been given to the spatial patterns of urban heat islands and how these patterns are affected by land use. In this study, we derive land surface temperature (LST) from Landsat 8 data over four time frames and analyze the relationship between urban thermal environments and urban land use. Landsat 8 Thermal Infrared Sensor (TIRS) and Operational Land Imager (OLI) band data are converted to top-of-atmosphere spectral radiance using radiance rescaling factors. At-satellite brightness temperature was retrieved and the land surface emissivity was calculated. In addition, Normalized Difference Vegetation Index and Normalized Difference Built-up Index were computed and their correlations with LST for each land use were examined. The results indicate that the highest maximum land surface temperature was observed in high density residential and commercial areas near city’s downtown. Coastal ar eas and areas near water bodies are found to have lower land surface temperatures. The results from this study can inform planning and zoning practices aimed at reducing the urban heat island effect and creating a cooler and more comfortable thermal environment for city residents. Keywords: Urban Heat Island, Land Surface Temperature, NDVI, NDBI, Land Use, Kruskal-Wallis Nonparametric Test. --------------------------------------------------------------------***---------------------------------------------------------------------- 1. INTRODUCTION In its Fourth Assessment (AR4), the Intergovernmental Panel on Climate Change (IPCC) indicated that ―observed warming has been, and transient greenhouse-induced warming is expected to be, greater over land than over the oceans‖ [1, ch3s3-2-2-2]. Various land uses possess thermal properties that can considerably impact the generation of extreme land surface temperatures [2]. A study conducted by Hamdi [3] in Brussels, Belgium, found a linear rise in the lowest and highest daily temperatures throughout the summer over the past fifty years, although the latter changes were not statistically significant. Built up areas are grouped in different use categories depending on ownership, function, and activity [4]. Urban Heat Islands (UHIs) develop as heat is emitted from a range of built-up surfaces, when favorable meteorological conditions (i.e., direction and velocity of wind, low water vapor content) are present [5]. An urban heat island effect is defined as the abrupt rise of the isothermic curve at the boundary of a highly urbanized area which modifies its thermal characteristics compared to those of the adjacent rural areas [5]. The United States Environmental Protection Agency (US EPA) differentiates between atmospheric UHIs and surface UHIs [2]. The atmospheric UHI is characterized by highest intensity during summer nights when air is stagnant while the surface UHI reaches its maximum heat release in the afternoon as sunlight is absorbed, then released back into the environment, by physical land structures. Historically, the study of urban heat island formation has relied on time series data from air temperature measurements with high temporal resolution [6,7]. Recent studies have employed remote sensing data in various spatial resolutions to study land surface temperatures (LST) [8]. Starting in 2013, thermal data became available through bands 10 and 11 of the Landsat 8 Thermal Infrared Sensor (TIRS). Land surface temperature (LST) derived from the radiance emitted from a surface and quantified using the radiative transfer equation is known as radiometric temperature [9]. It is equivalent to thermodynamic temperature for isothermal surfaces [9]. Excessive temperatures can exert extreme heat stress on humans resulting in heat exhaustion, fainting, sunburn, heat rash, and even death [10-11]. In 1995, an unprecedented heat wave in Chicago resulted in over 500 deaths in five days [12,13]. The mega-heat wave of 2003 claimed nearly 70,000 lives in sixteen countries throughout Europe [14]. People living in areas affected by heat waves increasingly resort to utilizing air conditioners when temperatures are at their most extreme. Higher energy consumption for operating cooling systems has economic as well as environmental impacts, the most notable of which are the increase in associated costs and greenhouse gas emissions [2,15]. Understanding of how patterns of land development and land use spatial distribution affect the formation of urban heat islands can inform urban design and planning practices and lead to successful mitigation of temperature extremes [16]. Studies have shown that among the most important factors of anthropogenic heat are urban form, urban land use, and