Climatic regionalization of the Brazilian Semi-Arid Region and its sociodemographic dynamics

The history of the Brazilian Semi-Arid (BSA) region is intrinsically linked to extreme climatic variations, such as prolonged droughts and increasing aridity, which severely impact water security, food security, and socioeconomic stability in the region. The aim of this study was to develop a homoclimatic typology for the BSA by identifying homogeneous climatic profiles and associating them with sociodemographic dynamics. Meteorological data, including precipitation, relative humidity, maximum and minimum temperatures, and wind speed, were obtained from the Brazilian Daily Weather Gridded Data, interpolated on a 0.1 & times; 0.1 degrees grid, covering the period from 1961 to 2020. Additionally, 18 sociodemographic indicators from the 1991, 2000, and 2010 censuses, carried out by the Brazilian Institute of Geography and Statistics, such as infant mortality and urbanization rates, were analyzed. Through cluster analysis using the Ward method, four distinct climatic zones (BSA I, II, III, and IV) were identified. This approach enabled the integration of meteorological and sociodemographic variables, providing a more precise characterization of the region. The results revealed rising temperatures, intensifying droughts, and increased vulnerability in areas such as BSA III, characterized by severe aridity and limited infrastructure. Despite improvements in sociodemographic indicators, regional inequalities persist, underscoring the importance of examining age and sociodemographic characteristics within the identified clusters. This analysis aims to understand the population-specific characteristics of each profile and their relationship with existing vulnerabilities, enabling the identification of specific patterns and supporting the formulation of more targeted and effective public policies.