Like vegetative and light or reflective surfaces, water bodies have a cooling effect on cities, reducing the Urban Heat Island effect. The average temperature at the river in this study was 1C less than at a reference point elsewhere in the city. Furthermore, the form of the landscape on the banks of an urban river can either propagate (increase) or diminish the cooling effects of the river. This study found that vegetated river banks increased the cooling effect of the river by a difference of 2C compared to river banks covered in hard engineering materials (concrete/asphalt), while opening river banks (rather than enclosing them with buildings or walls) permitted significant cooling effects to be felt up to a distance of 30 meters from the river.
Overall, the results indicate that high levels of vegetation next to the river increase the cooling on the bank, that opening up the streets to the river increases the propagation of cooling and that the surface nature of the surrounding materials [e.g. vegetation versus concrete] can have a more significant effect on the air temperatures than the presence of the river [Hathaway & Sharples 2012: 20].
Overall, the results indicate that high levels of vegetation next to the river increase the cooling on the bank, that opening up the streets to the river increases the propagation of cooling and that the surface nature of the surrounding materials [e.g. vegetation versus concrete] can have a more significant effect on the air temperatures than the presence of the river [Hathaway & Sharples 2012: 20]. |
Hathaway, E.A. & S. Sharples, 2012, The interaction of rivers and urban form in mitigating the Urban Heat Island effect: a UK case study, Building and Environment 58, https://www.sciencedirect.com/science/article/pii/S0360132312001722.