Interações entre arborização urbana, temperatura de superfície e ilhas de calor no município de Cascavel-PR (2014- 2024)

Abstract

This study examined the spatial variation of Land Surface Temperature (LST) in the municipality of Cascavel, Paraná State, Brazil, for the years 2014 and 2024, with a particular focus on the role of urban vegetation in regulating surface temperature. Accelerated urbanization, coupled with the replacement of vegetated areas by impermeable surfaces, has intensified urban heat island (UHI) effects, posing challenges to environmental quality and public health. The research employed remote sensing techniques, utilizing Landsat 8 satellite imagery processed with QGIS software. LST data from the summer months (January, February, and March) of both years were analyzed, alongside vegetation distribution assessed through the Normalized Difference Vegetation Index (NDVI). Surface temperatures were derived from the satellite’s thermal band, while NDVI calculations employed the near-infrared and red spectral bands. For comparative and validation purposes, descriptive statistical analyses were conducted, including the Shapiro-Wilk test to assess data normality and Pearson’s correlation coefficient to examine the relationship between vegetation cover and surface temperature. The findings confirmed a significant increase in UHI intensity in Cascavel over the ten-year period, largely attributed to unplanned urban expansion and the reduction of vegetative cover. Although a slight increase in maximum NDVI values was observed, the existing vegetation proved insufficient to mitigate surface warming. The weakening correlation between vegetation and LST over time further indicates a declining capacity for thermal regulation. This study underscores the urgent need for more effective public policies focused on expanding urban green areas and promoting sustainable urban planning to mitigate local climatic impacts and enhance urban resilience.