Evaluation of albedo enhancement to mitigate impacts of urban heat island in Rome (Italy) using WRF meteorological model

Abstract

The extreme effects of urban heat island (UHI) on energy consumption, air quality, and human health are significantly detrimental. Increasing the albedo of urban surfaces has been proposed as a potentially efficient mitigation strategy. In this study the Weather Research and Forecasting (WRF) mesoscale model has been used to simulate the urban climate of Rome (Italy).Four different scenarios have been analyzed: the Base Scenario as control case; the Base-ALB Scenario, in which the albedo of roof, walls and road have been increased; the Morph Scenario in which the morphology of urban area has been parameterized more accurately; the Morph-ALB Scenario in which the urban albedo of the improved model has been increased.This study demonstrates that a more accurate parametrization of the urban morphology leads to a more accurate representation of UHI phenomenon. The simulation results show that albedo increase leads to the decrease of the 2-m air temperature at day-time and at night-time. Albedo increase offers very promising results in terms of UHI mitigation, reducing the temperature in the urban area by up to 4°C at daytime and a little increased (up to 1°C) in some locations at night time, compared to the control cases.