Planting lots of trees is one of many strategies being pursued to combat climate change. Trees are storehouses of carbon from the atmosphere and planting more of them helps remove carbon dioxide. But trees do more than that. Trees are natural air conditioners in cities.
Trees significantly cool urban environments by providing shade and via a process called evapotranspiration by which they release water vapor into the air, which provides cooling. This helps mitigate the urban heat island effect. Areas under trees in cities can be as much as 25 degrees cooler than in unshaded areas covered in asphalt.
The city of Paris has laid out a plan to help the city prepare for increasing amounts of extreme heat. The goal is to replace 60,000 parking spaces across the city with trees by the end of this decade. The plan to rip up parking spaces is part of a greater aim to create more than 700 acres of green space by 2030. The Paris plan also includes creating more car-free zones and installing reflective roofs on 1,000 public buildings. Nearly 80% of the buildings in Paris have zinc roofs – an affordable, corrosion-resistant and pretty much inflammable innovation of the 19th century. However, these roofs can heat up to 194 degrees on a summer day, transferring heat into largely uninsulated top-floor garrets below.
Elsewhere in Europe, Danish lawmakers have agreed on a plan to rewild 10% of the country’s farmland and plant one billion trees. According to the Danish government, this plan would bring about the biggest change to the Danish landscape in over 100 years.
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To Cope with Extreme Heat, Paris Will Swap Parking Spaces for Trees
Photo, posted April 11, 2014, courtesy of Val H. via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio
