Alissa Walker+ Your Authors @awalkerinLA I'm a writer, a gelato-eater, and a walker in LA. Urbanism editor at @Curbed. Easter-themed Peeps only, please. More 👧🏼👶🏼 and 🚲🚶🏼‍♀️🚍 on Instagram. Jul. 19, 2019 1 min read + Your Authors

This week's dangerous heat wave is a good time to talk about how putting trees in the right places can help cool cities and could even end up saving lives. 

Trees do a lot for us, but the way you should be thinking about them on a 100-degree day is like a giant dual-function air conditioner/air purifier. In fact, a mature, healthy tree has the cooling benefits of 10 window-mounted AC units. 

Trees can also help clean the air, filtering out toxic pollutants emitted by the burning of fossil fuels. This includes the fine-particulate matter from vehicles that create especially dangerous breathing conditions during hot summer days. 

Heat and smog are two of the greatest health risks facing U.S. cities. Extreme heat kills more people than all other weather disasters combined. Air pollution kills more people than smoking. These numbers will go up due to climate change. 

Trees can provide the most effective, efficient, and immediate form of urban climate action. The problem is, most U.S. cities have been losing tree canopy at an astonishing rate over the last decade. 

Urban heat island effect can make cities 15+ degrees hotter than rural areas, with temperatures staying stubbornly high after sunset. When air temperatures remain above 80 degrees overnight, humans are unable to regulate their own body temperatures. 

You can follow @awalkerinLA.


Tip: mention @threader_app on a Twitter thread with the keyword “compile” to get a link to it.

Enjoy Threader? Sign up.

Since you’re here...

... we’re asking visitors like you to make a contribution to support this independent project. In these uncertain times, access to information is vital. Threader gets 1,000,000+ visits a month and our iOS Twitter client was featured as an App of the Day by Apple. Your financial support will help two developers to keep working on this app. Everyone’s contribution, big or small, is so valuable. Support Threader by becoming premium or by donating on PayPal. Thank you.

Follow Threader