夏天走路太晒？西班牙这个地图APP可开启“清凉”模式
App maps shady spots to guide Barcelona walkers along cooler routes

A new app promises to help Barcelona residents find the shadiest route between two places to avoid extreme heat.

Cool Walks, a routing tool for pedestrians first developed at a data visualisation contest, aims to show users a variety of walking routes to take for their intended destinations.

Users can choose the most direct route, a shady route that may take a little longer, or they can set the app to “vampire mode”, which avoids direct sunlight at all costs. Users can also use the app to find drinking fountains, or places to shelter from the sun.

The app uses a tool called Lidar to create high-resolution models of ground elevation, accurate to within 10cm. This information is combined with data on the sun’s path to work out where is in shade at any given time of day.

Marc Montlleo, director of environmental projects at Barcelona Regional, said the vampire mode was created from taking “the most extreme form of the data algorithm”.

Barcelona is looking to use green spaces and trees as part of its efforts to mitigate the effects of global heating. The city’s 20-year tree masterplan aims to increase the proportion of land covered by trees from 25% to 30%.

Although the tool only maps one neighbourhood of Barcelona, it is hoped the research will provide information on how the city can adapt to extreme heat to protect its citizens and economy.

Heatwaves kill more people than any other climate risk. According to C40, a climate leadership group made up of 97 cities around the world, extreme heat events in cities can cause mortality increases of up to 14%, as well as lower workforce productivity and damage infrastructure such as roads and rail lines.

Jon Burke, a former councillor for Hackney in London, who was responsible for a massive expansion of tree planting in the borough, said: “I think we should view this particular kind of app as an interim measure to reduce the impacts of extreme heat … while cities rapidly invest in urban canopy cover and broader green infrastructure.