Effectiveness of Road Cool Pavements, Greenery, and Canopies to Reduce the Urban Heat Island Effects

The ongoing climate change is manifesting itself through the increasing expansion of Urban Heat Island (UHI) effects. This paper evaluates the microclimate benefits due to cool road pavements, greenery, and photovoltaic canopies in a parking lot in Fondi (Italy), identifying the best strategy to counteract the negative effects of UHIs. The ENVI-met software allowed a microclimatic analysis of the examined area in July 2022 through the comparison of the thermal performances between the current asphalt pavement and ten alternative scenarios. The proposed layouts were investigated in terms of air temperature (AT), surface temperature (ST), mean radiant temperature (MRT), and predicted mean vote (PMV). The results showed that the existing asphalt pavement is the worst one, while the cool pavement integrated with vegetation provides appreciable benefits. Compared to the current layout, a new scenario characterized by light porous concrete for carriageable pavements and sidewalks, concrete grass grid pavers for parking stalls, a 2-m-high border hedge, and 15-m-high trees implies reductions of AT above 3 degrees C, ST above 30 degrees C, MRT above 20 degrees C, and a maximum PMV value equal to 2.2.