Measuring the impact of different green space layouts on the urban heat island and climate in a semi-arid region: Case of Ain Smara city (Algeria)

Abstract

The urban microclimate and climate are positively impacted by green spaces in neighbourhoods. Through the creation of a cooling effect via shade and evapotranspiration, they contribute to regulating the urban climate and reducing the urban heat island (UHI). They also use energy, emit pollutants, release oxygen, absorb carbon dioxide, and produce shade. Green spaces, such as parks and gardens, are essential for creating sustainable and resilient urban environments. They improve air quality, regulate temperature, and promote the well-being of residents. In order to reduce the urban heat island (UHI), this study aims to evaluate the effects of spatio-temporal changes in green cover on the urban climate. This is accomplished by examining how changes in the spatial arrangement of green cover in Ain Smara City (Algeria) between 1992 and 2021 have affected the land surface temperature (LST). The use of remote sensing offered us a relevant means to achieve this objective. Images from Landsat 5TM, 7ETM+, and Landsat 8 OLI/TIRS were downloaded and analyzed using ArcGis 10.4 software to extract the Normalized Difference Vegetation Index (NDVI), the land surface temperature (LST), and the Normalized Difference Moisture Index (NDMI). The analysis of the vegetation index (NDVI) made it possible to quantify and evaluate the impact of vegetation on the urban microclimate. The results demonstrated a positive correlation between vegetation cover and decreasing surface temperature, as well as a positive relationship between vegetation cover and increasing humidity.