Effect of Urban Green Walls on Reduction of Temperature in Microclimates and Urban Heat Island

The speedy process of urbanization is destroying urban green spaces and causing a lot of problems including urban heat island. To restore back the nature into the urban landscape and to set up a balanced cycle among the climate factors, green surfaces can be the key element to this transformation. For this purpose, vegetation can be very helpful through its cooling effect, evapotranspiration and shading.
The main method used in this research is field study, in which, by a data logger, air temperature and relative humidity were recorded in certain points with definite distances from two green walls.
Findings: According to the measurements, green surfaces reduce the temperature of their surrounding area by 0.63 to 1.0 ˚C during warm seasons. Furthermore, during cold seasons, temperature of the areas where are covered with vegetation is higher by 2.43 to 1.76 ˚C.
The obtained results indicate that during warm seasons, temperature of green-wall surrounding area is cooler up to 1.0 ˚C and during cold seasons it is warmer up to 3.0 ˚C. Therefore, building vertical green structures creates an appropriate environment by reducing the temperature during warm seasons and increasing the temperature during cold seasons, and makes a proper microclimate at their surrounding area.