In order to verify the increased comfort level, which can be achieved by increasing the shade provided by greenery in urban areas, we conducted the following experiment in the summer of 2007. We created a shaded green area in Tokyo with trees planted in containers, and measured the physiological and psychological effects on people and the cooling effect on the environment. When we measured the relative temperature before and after the installation (the green shaded area and the paving blocks) and compared the results inside the green shaded area against an un-shaded area, we found that a reduction of 2~3degree C had been achieved. Furthermore, we carried out a physiological test of the effects on twenty subjects and by testing their saliva we found that there had been a notable decrease in the level of cortisol. In a mood-profiling test (Profile of Mood States) we found that the subjects' irritability and aggression scores were also significantly lower, when measured before and after, under the shaded green area. These results indicate that even with a small area of shaded greenery, a certain level of environmental cooling can be achieved and they also demonstrate that there is an improvement in the physiological and mental state of people living in urban environments, proving, therefore, with quantitative data that there is a possibility for green shaded areas to make city life more pleasant.
