143
surfaces in substitution of asphalt and pavements. The findings showed a welldefined ranking in the impact of mitigation measures (Fig. 6.10).
“Green courtyard with trees” was the most effective mitigation measure. A
reduction of temperatures was evident for the entire course of the day. The “green
roofs” scenario showed a peak of the cooling effect with respect to the control run
at a height of around 10 m, with a slightly smaller impact at ground level. On the
contrary, “cool roofs” and “pervious courtyard” scenarios showed a peak of cooling
at ground level with a relevant decrease of the impact going upwards. On the other
hand, scenario with “cool walls” showed a negative effect in terms of mitigation of
urban heat island. The cooling effect induced in this scenario was possibly explained
by the unsatisfactory consideration of heat balance in model equation for
buildings.
6.2.4 Experimental Environmental Quality Index to Assess
the UHI’s Mitigation Actions in a Building Lot
As described in the previews paragraphs, in the Villaggio Artigiano pilot area the
following main environmental issues are taken into consideration:
– reduction of the Urban Heat Island
– reduction of energy consumption
– reduction of the hydraulic risk (not strictly connected to UHI phenomenon)
Fig. 6.10 Vertical profiles of “all day” mean differences between each scenarios, labeled as indicated in the legend, and the control run
6 UHI in the Metropolitan Cluster of Bologna-Modena...
surfaces in substitution of asphalt and pavements. The findings showed a welldefined ranking in the impact of mitigation measures (Fig. 6.10).
“Green courtyard with trees” was the most effective mitigation measure. A
reduction of temperatures was evident for the entire course of the day. The “green
roofs” scenario showed a peak of the cooling effect with respect to the control run
at a height of around 10 m, with a slightly smaller impact at ground level. On the
contrary, “cool roofs” and “pervious courtyard” scenarios showed a peak of cooling
at ground level with a relevant decrease of the impact going upwards. On the other
hand, scenario with “cool walls” showed a negative effect in terms of mitigation of
urban heat island. The cooling effect induced in this scenario was possibly explained
by the unsatisfactory consideration of heat balance in model equation for
buildings.
6.2.4 Experimental Environmental Quality Index to Assess
the UHI’s Mitigation Actions in a Building Lot
As described in the previews paragraphs, in the Villaggio Artigiano pilot area the
following main environmental issues are taken into consideration:
– reduction of the Urban Heat Island
– reduction of energy consumption
– reduction of the hydraulic risk (not strictly connected to UHI phenomenon)
Fig. 6.10 Vertical profiles of “all day” mean differences between each scenarios, labeled as indicated in the legend, and the control run
6 UHI in the Metropolitan Cluster of Bologna-Modena...