[Climactions project. Urban Heat Island mitigation in Rome as an opportunity for regeneration: the case study of Piazza Mancini].

OBJECTIVES

to estimate the improvement of thermal comfort at a microclimatic level after using Nature-based Solutions (NBS) and albedo mitigation strategies in a square located in a densely built-up district of the city of Rome and subject to the phenomenon of Urban Heat Island.

DESIGN

on the basis of the microclimatic simulation results of the current conditions of the area, obtained using the ENVI-met software, several microclimate cooling scenarios were developed and simulated; these scenarios included the integration of different layers of vegetation (herbaceous, shrubby, and arboreal) with different configurations and in different quantities and of different surfaces with high albedo index.

SETTING AND PARTICIPANTS

the studio area is Piazza Mancini, located in the Flaminio district of Rome.

MAIN OUTCOME MEASURES

the main outcome measures calculated from the simulations were the intensity of the Urban Heat Island (UHI) and the Universal Thermal Climate Index (UTCI) to estimate the perceived discomfort associated with heat and the potential improvement of such perceptions through the scenarios considered.

RESULTS

the simulations based on data from 22.07.2021 showed a progressive reduction of UTCI and of the UHI in the three considered scenarios. From the first scenario, which provides for greening and replacement of the asphalt with a higher albedo, it goes to the second and third scenario, which included also changes in the structure of the square (scenario 2) and functional optimization by inserting a shading structure (scenario 3). Scenarios 2 and 3 show a decrease in UTCI of almost 7ºC and UHI of about 2ºC compared to the actual state.

CONCLUSIONS

the three presented scenarios show how it is possible to improve the conditions of the healthiness of space (reducing the UHI by about 1.5°C) and that it is possible to transform mitigation actions into opportunities for the regeneration and enhancement of urban public spaces.