Google introduces tool to help keep cities cool

By Rahul Vaimal, Associate Editor
  • Follow author on
Representational Image

Google has unveiled a tool that could help cities keep their residents cool by mapping out where trees are most needed.

Since buildings and asphalt trap heat, cities tend to be warmer than neighboring regions. Planting more trees in communities where they are scarce is a simple way to cool urban areas down.

Aerial imagery and Google’s AI (Artificial Intelligence) are used by Google’s new Tree Canopy Lab to find out where every tree is in a city. In addition to extra data on which neighborhoods are more heavily populated and are more vulnerable to high temperatures, Tree Canopy Lab presents the detail on an interactive map. The hope is that in these areas, planting new trees will help cities adjust to a warming world and save lives during heat waves.

Google has piloted the Tree Canopy Lab In the US city of Los Angeles. There are details on hundreds of cities on the way, the company states. City planners interested in using the tool in the future can reach out to Google.

Google says that when it comes to taking inventory of their trees, that’s often achieved by sending people to survey each block, their new tool will save cities. A city like Los Angeles uses LIDAR technology to map their urban forest, which uses a laser sensor to detect the trees, but the process is costly and slow. On the other hand, Google’s latest service is free to use and will be frequently updated using pictures that the company already takes by plane for Google Maps.

More than half of Los Angeles residents live in areas where trees shade less than 10% of their neighborhood, Tree Canopy Lab discovered. It also found that 44 percent of individuals live in places with extreme heat risk. According to a report published this year by researchers at NASA’s Jet Propulsion Laboratory, heat waves in Los Angeles County have become longer, more frequent, and more intense over the past 50 years.

Tree Canopy ImageOne of the most well-documented consequences of climate change is extreme heat. It kills more people every year than any other disaster connected to the weather. Because of what’s known as the urban heat island effect, scorching temperatures can be even more dangerous in cities. On average, urban areas with greater heat-trapping surfaces and less greenery can be up to 6 degrees Fahrenheit warmer than rural areas. The temperature differential will rise to 22 degrees at night, a time that’s critical for our bodies to recover from a hot day.

Trees cool down a hot neighborhood in a number of ways. They shade the people and buildings from the sun. And as temperatures rise via evapotranspiration, they release moisture, a mechanism similar to the way our bodies cool down through sweating. According to experts, these two mechanisms lower peak summer temperatures by up to nine degrees Fahrenheit.

The Tree Canopy Lab of Google found that neighborhoods with the highest heat risk appeared to be more densely populated with people, but less densely covered with trees. Basically, there are fewer resources to deal with heat illness and death at places that are most vulnerable to it.