The assessment relationship between land surface temperature (LST) and built-up area in urban agglomeration. Case study: Cluj-Napoca, Romania

Abstract

The built-up area in many large cities has shown a continuous growth during the last decades. In the present study we aimed to evaluate the connection between Land Surface Temperature and built-up areas within the urban areas, based on statistical correlation. Experiments were performed in the surrounding area of Cluj-Napoca - one of the most dynamic urban agglomerations of Romania - in order to determine LST and built-up areas during the period 2007-2015. Detection of changes in land cover and in Land Surface Temperature was possible using Landsat satellite imagery. The extraction of the built-up area was achieved by using the Maximum Likelihood classification method, and for estimation of Land Surface Temperature (LST) we have used the single channel algorithm. Investigations of the degree of dependence between LST and built-up area revealed a direct statistical relationship between the two analyzed variables. Results have shown that areas with LST higher than 35°C generally coincide with large hypermarkets and industrial areas of the city. Satellite imagery proved to be an important source of data in detecting changes in surface of the urban area and in estimating temperature from the land surface during the reference period.