Researchers at Future Cities Laboratory, Singapore – ETH centre, have used Google Street View to understand and map out the shade provided by trees in city areas thereby paving way for further studies using the huge Street View data set for the enhancement of green spaces for urban sustainability.
The importance of green spaces is known to all particularly in the urban areas and yet there has never been any such development for quantification of the shade provided to the surface by trees which eventually help mitigate flood risk, cool the urban micro-climate and provide suchlike eco-system services.
Using 100,000 panoramic images from the Google Street View researchers carried out a study to understand tree coverage at regular intervals of 50 metres on the Singaporean streets. In the study researchers covered more than 80 per cent area of the city. The high spatial resolution images facilitated researches to quantify the solar radiation proportion hitting the earth’s surface, through which the amount of shade provided by tress was estimated.
Results of the study show that on an average the tree canopies have been able to seize 8 per cent of the solar rays, whereas at some locations the contribution of canopies in intercepting the radiations has raised up to 50 percent also. The study clearly indicates the worthy role of green spaces, particularly the trees, in urban sustainability.
According to Dan Richards, a postdoctoral researcher at the Future Cities Laboratory and the project’s coordinator, the study suggests the importance of trees in the tropical cities where the heat effect is comparatively heavy throughout the year. The shade in these tropical regions is also important considering the thermal comfort of the inhabitants.
This method that uses Google Street View images can be adapted to other tropical cities as well to quantify the green space coverage which can facilitate adoption of measures to mitigate the urban heat effect and thus enhance urban sustainability.