The impact of urbanisation on local climate: a case study from Palmas, Brazil

Abstract

The relationship between growing rates of urbanisation and city warming has been evaluated in a very large number of urban climate studies. The work detailed here has focused on remote-sensing data, looking at changes in urbanisation over time in one of the newest cities in Brazil, i.e. Palmas in the northern region of the country, which serves as capital city of Tocantins. The youngest state in Brazil, Tocantins was only founded in 1988, with the construction of Palmas as capital commencing in 1989. Measured meteorological data were used to assess local climate changes in typical years, whereas urbanisation levels, generated for stepwise increments of 10 years, were obtained from the identification of vegetated and built-up classes in satellite imagery. Results suggest that changes in local climate were not always related to ongoing urbanisation in Palmas. Equally, despite promising changes in patterns of distribution of vegetation in given areas of Palmas over time – with an increase in high NDVI levels in 2021 that would potentially ameliorate local climate – thermal benefits did not prove to be detectable at the reference meteorological station.