The Impact of Urban Tree Planting on Climate Regulation: a Case Study in Garanhuns, Brazil

Objective: This study evaluates the influence of urban tree planting on microclimatic variables, particularly air temperature and relative humidity, in the municipality of Garanhuns, Brazil. It investigates whether vegetation cover directly contributes to thermal regulation in urban and rural areas. Theoretical Framework: The research is based on concepts of urban microclimate, urban heat islands, and ecosystem services provided by green infrastructure, supporting the notion that vegetation mitigates thermal extremes and improves urban environmental quality. Method: A mixed-method approach combined field data and remote sensing. Air temperature and relative humidity were measured in situ at eight urban sites, while vegetation cover was analyzed using the Normalized Difference Vegetation Index (NDVI) from Landsat 8 imagery. Land Surface Temperature (LST) was also extracted to evaluate surface heating. Results and Discussion: Sites with greater vegetation cover showed lower air temperatures and higher relative humidity. A negative correlation was observed between NDVI and air temperature, and a positive one between NDVI and humidity. However, NDVI showed no significant correlation with LST, suggesting surface temperature is influenced by factors like material type, topography, and solar exposure. Research Implications: The findings emphasize the need to integrate urban forestry into climate adaptation strategies. Increasing vegetation in planning can enhance thermal comfort and urban health, especially in dense areas with limited green space. Originality/Value: This study contributes empirical evidence of vegetation’s moderating effects on microclimates in a Brazilian highland city, while also highlighting NDVI’s limitations as a sole predictor of surface temperature in complex landscapes.