210
Finally, a deeper analysis of the thermal comfort in Prato della Valle was
performed. This very popular circle is characterized by a central green island
delineated by a channel decorated by statues and encircled by a wide asphalt circle
road (Table 7.6 ). Because of the extension of the square, six different positions were
fi xed for the measurements.
The results indicate a difference of 0.5–1 °C in the air temperature between position 4 (on the green) and external positions near urban streets (1, 2, 3, 6); a quite
larger difference in mean radiant temperature was measured, with a maximum of
7 °C, because of the different surface characteristics (emissivity, thermal inertia and
water storage capacity) and SVF (higher) at the centre of the square with respect to
outer positions.
Table 7.5 Data obtained in measurement sessions in a lateral dirt road of via Roma (see also Fig.
7.1 ). The “X” refer to the point of measurement. Thermal comfort indexes refer to a person with
summer clothing (0.5 clo) and slight activity level (80 W above the basal metabolism) (Google
Earth)
Via Roma (SVF ≈ 1)
Date
30-Jul
31-Jul
2-Aug
Hour
22:46
22:52
16:53
Temperature (°C)
21.4
22.9
33.6
UHI Intensity (°C)
0.5
0.4
0.8
Relative humidity (%)
80.8
61.2
35.8
Humidity ratio (g v kg a
−1 )
13.0
10.7
11.6
Wind velocity (m s
−1
)
0.0
0.2
2.4
T globe (°C)
19.0
21.6
T radiant mean (°C)
18.4
20.6
PMV
−0.5
−0.4
PET (°C)
21.6
21.4
SET* (°C)
15.8
17
Global radiation (W m
−2
)
502
M. Noro et al.
Finally, a deeper analysis of the thermal comfort in Prato della Valle was
performed. This very popular circle is characterized by a central green island
delineated by a channel decorated by statues and encircled by a wide asphalt circle
road (Table 7.6 ). Because of the extension of the square, six different positions were
fi xed for the measurements.
The results indicate a difference of 0.5–1 °C in the air temperature between position 4 (on the green) and external positions near urban streets (1, 2, 3, 6); a quite
larger difference in mean radiant temperature was measured, with a maximum of
7 °C, because of the different surface characteristics (emissivity, thermal inertia and
water storage capacity) and SVF (higher) at the centre of the square with respect to
outer positions.
Table 7.5 Data obtained in measurement sessions in a lateral dirt road of via Roma (see also Fig.
7.1 ). The “X” refer to the point of measurement. Thermal comfort indexes refer to a person with
summer clothing (0.5 clo) and slight activity level (80 W above the basal metabolism) (Google
Earth)
Via Roma (SVF ≈ 1)
Date
30-Jul
31-Jul
2-Aug
Hour
22:46
22:52
16:53
Temperature (°C)
21.4
22.9
33.6
UHI Intensity (°C)
0.5
0.4
0.8
Relative humidity (%)
80.8
61.2
35.8
Humidity ratio (g v kg a
−1 )
13.0
10.7
11.6
Wind velocity (m s
−1
)
0.0
0.2
2.4
T globe (°C)
19.0
21.6
T radiant mean (°C)
18.4
20.6
PMV
−0.5
−0.4
PET (°C)
21.6
21.4
SET* (°C)
15.8
17
Global radiation (W m
−2
)
502
M. Noro et al.