Effect of green areas on summer air temperatures in Florence

In this study, the relationship between the percentage of green areas (green cover ratio - GCR) and intra-urban minimum and maximum temperature was investigated during the summer period. A network of air temperature sensors (HOBO® PRO series Temp/RH Data Logger, Onset Computer Corporation) was used to collect intra–urban thermal data in Florence (Italy). Temperature data were related to GCR calculated on areas of different size (from 10 to 250 m radius) centred on each sensor. Our results evidence a clear negative relationship between both minimum and maximum temperature values and GCR. It was correlated with maximum air temperatures only in areas of small radius, and with minimum air temperatures in all the considered areas. These results can be useful for urban planners to evaluate the effect of the increase of green areas in an urban environment.