The major changes cities need to withstand a warmer planet

When being shady is a good thing

Trees, ya’ll. Trees.

It might seem painstakingly obvious to list this first, but trees have a massively positive impact on their surrounding environment – especially in urban areas typically devoid of vegetation.

Trees can reduce the heat of sidewalks by 20 degrees, provide a 12 degree difference in temperature under shaded areas, and promote cleaner air in densely populated boroughs where traffic flow is especially high.

The water vapour released through their leaves helps to cool us down even though we can’t see this happening, which is why rural areas tend to stay cooler than cities. The problem is that most urban streets are typically devoid of trees – even more so in impoverished neighbourhoods.

Across Europe, numerous cities such as London, Paris, and Spain have already set out plans to re-green central areas and re-wild their nearby forests to deal with heat and air pollution.

How they approach these projects and the speed at which they are completed will depend on local soil, surrounding ecosystems, and investments from stakeholders.

Building designs with ventilation in mind

European buildings weren’t constructed with the prospect of a climate crisis in mind. For the most part, the oldest buildings have insufficient airflow and the materials used to construct them actually retain heat on hot days.

In some places, air conditioning systems have been added in at a later date. But this only exacerbates the problem as AC units are energy-intensive, releasing more greenhouse gases into the atmosphere, which ultimately warm our planet further.

In other parts of the world, architects have been factoring in relief from hot days for centuries. In ancient Egypt and throughout the Persian Empire, airflow was captured by built-in tower structures called ‘windcatchers’ which are still used in the Middle East today.

Without the need for electricity, windcatchers harness breeze, filter out debris, and direct cool air down into the interior of buildings below. As AC units account for one fifth of electricity consumption globally, this eco-friendly design is becoming increasingly attractive in the eyes of Western architects.

See a concrete road, paint it white

Anyone who has stepped barefoot on concrete in the summer has likely gotten burned, and it only takes this experience in childhood to know that roads absorb a ton of heat.

To combat this heat storage, an ultra-reflective white paint called CoolSeal has been put forward as a solution. The paint has already been layered on top of numerous buildings and roads in US cities.

Streets layered with CoolSeal are 10 to 15 degrees cooler than other areas in LA. As a result, surrounding neighbourhoods are also cooler, there have been less heat related deaths, and the use of air conditioning has dropped – curbing costs and CO2 emissions.

This reflective-paint technology does have its drawbacks though, as every mile painted costs governments a hefty $40,000. To many nations, rooting a couple rows of trees down might seem like a more economical approach.

Without stating the obvious need to phase out fossil fuels like, yesterday – let’s hope we also see more climate adaptive measures popping up in our cities soon. Seriously, we’re burning up over here in London.