Anyone who’s cycled through a rural area and into the suburbs or city can tell you just how dramatic the temperature change can be.
Any strategy to cool cities would have a positive impact on anyone living or passing through them.
There’s a road by my house that dips down in a ravine then comes back up. When on my motorcycle on a hot day you can really feel the difference.
Concrete soaks up, stores and radiates a lot of heat from the sun. Trees thrive on sun and provide shade for humans.
They also shade the concrete
They also transpire, which further reduces heat — marginally but noticeable in aggregate.
Also white (but high emissivity) paint. Painting every dark urban and suburban surface white would reduce total radiative forcing somewhere around a watt.
White paint gets covered with grime and turns dark. It also flakes off and degrades into microplastics and toxic crud. Either way it requires ongoing maintenance and regular repainting.
Leaves, otoh, are self-healing and 100% biodegradable.
Sure, if you have to paint something anyway, you may as well use reflective paint. But wherever you can put a tree you should.
