Análise da expansão urbana, temperatura da superfície e condições bioclimáticas futuras em uma cidade tropical úmida do Brasil

Abstract

Extreme events cause economic and social losses. Vulnerable countries like Brazil are particularly affected. Furthermore, changes in land use and land cover associated with the urbanization process and climatic variability are the primary factors controlling urban climates. The overall objective of this study was to analyze long-term urban expansion and surface temperature and estimate future bioclimatic conditions for the city of João Pessoa, PB, between 2031 and 2080. Micrometeorological data on temperature and air humidity collected at ten different points between 2011 and 2018 were used to calculate the Effective Temperature Index Resulting from the Wind Effect (ETv) and Thom's Discomfort Index (IDT) for the city of João Pessoa,PB. Satellite images from Landsat 5/TM for 1991, 2006, and 2010, as well as Landsat 8/OLI for 2018, were utilized, and the maximum likelihood classification method was applied to classify the images and analyze urban expansion. Additionally, the NDBI index was used to verify the built-up area over time, as well as surface temperature, using thermal band satellite images. To better analyze the data on bioclimatic factors, non-parametric Mann-Kendall tests and the Sen's Test were employed. From the results obtained, there was an increase in the built-up area and surface temperature in the city of João Pessoa between 1991 and 2018, primarily in the neighborhoods of Geisel, Aeroclube, Valentina, Distrito Industrial, Cristo Redentor, and Mangabeira. Based on these findings, a significant increase in discomfort in the urbanized areas of the city from 2010 to 2018 was observed, associated with the rise in average temperature since 1991. The projection of future scenarios indicates a substantial increase in air temperature and, consequently, thermal discomfort for the city of João Pessoa, PB, between 2031 and 2080, with a more significant contribution from the IDT calculation and, on the other hand, mitigated by the wind factor (ETv). Nevertheless, a concerning future scenario is still estimated for the coming decades, requiring urgent implementation of urban public policies to mitigate the impacts of future bioclimatic conditions in the city.