Many studies explain impacts of urban heat island (UHI) on energy consumption, air quality, and human health. Since the impact of UHI is detrimental, many researchers have been proposing solutions to weaken the UHI. 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). A multi-layer urban canopy model (UCM) has been coupled to the mesoscale model to better estimate the momentum, heat, and turbulent kinetic energy budget of the urban canopy. Four different scenarios have been analyzed. The Base Scenario is the idealized case based on actual urban structure and characteristics. The physics models of the Base Scenario have been accurately set so that it can well reproduce the overall spatial and temporal characteristics of urban climate and its results are consistent with data observed in the local weather stations. In the Albedo-Base Scenario, the albedo of roof, walls and road have been increased. The simulation results show that the 2-m air temperature is decreased in day-time and in night-time. In the Morph Scenario the morphology of urban area has been parameterized more accurately. Mean height of buildings, area density, and plan area density have been estimated in a more realistic way for UCM. The basic meteorological variables are better reproduced by the Morph model and UHI intensity estimation is improved. Finally, in the Albedo-Morph scenario, the urban albedo of the improved model has been increased and the UHI mitigation potential of albedo control strategy has been quantified. This study demonstrates that a more accurate parametrization of the urban morphology leads to a more accurate representation of UHI phenomenon. 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 in some locations at night time, compared to the control cases. It would allow thus to reduce energy consumption and to improve air quality and human health in the city of Rome in summertime.
Evaluation of albedo enhancement to mitigate impacts of urban heat island in Rome (Italy) using WRF meteorological model
MORINI, ELENA;ROSSI, Federico;COTANA, Franco;
2016
Abstract
Many studies explain impacts of urban heat island (UHI) on energy consumption, air quality, and human health. Since the impact of UHI is detrimental, many researchers have been proposing solutions to weaken the UHI. 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). A multi-layer urban canopy model (UCM) has been coupled to the mesoscale model to better estimate the momentum, heat, and turbulent kinetic energy budget of the urban canopy. Four different scenarios have been analyzed. The Base Scenario is the idealized case based on actual urban structure and characteristics. The physics models of the Base Scenario have been accurately set so that it can well reproduce the overall spatial and temporal characteristics of urban climate and its results are consistent with data observed in the local weather stations. In the Albedo-Base Scenario, the albedo of roof, walls and road have been increased. The simulation results show that the 2-m air temperature is decreased in day-time and in night-time. In the Morph Scenario the morphology of urban area has been parameterized more accurately. Mean height of buildings, area density, and plan area density have been estimated in a more realistic way for UCM. The basic meteorological variables are better reproduced by the Morph model and UHI intensity estimation is improved. Finally, in the Albedo-Morph scenario, the urban albedo of the improved model has been increased and the UHI mitigation potential of albedo control strategy has been quantified. This study demonstrates that a more accurate parametrization of the urban morphology leads to a more accurate representation of UHI phenomenon. 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 in some locations at night time, compared to the control cases. It would allow thus to reduce energy consumption and to improve air quality and human health in the city of Rome in summertime.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
