Climate change is increasing the average temperatures of cities around the world, which forces inhabitants to adjust to entirely new climates their cities weren’t designed for. In Spain, the city of Seville is expected to have the climate of Marrakesh in a few years time so the city needs to find new ways to cool down. They are currently experimenting with an old technique perfect by ancient people: use water that cools in the night to cool the city during the day.
One of the coolest spots in Seville, Spain, is the site of CartujaQanat, an architectural experiment in cooling solutions that relies not on air conditioning but on natural techniques and materials. Inspired by ancient tunnels dug to bring water to agricultural fields in what is today Iran, the $5.6 million structure uses a network of aqueducts, pipes and solar-powered pumps to cool water at night and then turn it into cold air during the day.
Seville is among the world’s hottest cities looking for new ways to cool down and save lives. Yet despite the project’s early promises, the CartujaQanat remains in limbo amid financial and political hurdles, Laura Millan reports.
In the cold of winter you might not be thinking of the nice hot summer days as a negative thing. In the winter when temperatures get really low people suffer from hypothermia or worse, whereas in heat they can suffer from heat stroke or worse. When it comes to the heat there’s a nice and simple solution of planting trees.
In urban environments tree coverage can literally save lives by having a minium of 30% of urban space shaded by trees. Not only will the trees reduce heat in their immediate area they will provide cleaners air and a nicer place to be.
We found substantial variation in UHI death rates across European cities. In 2015, Gothenburg in Sweden recorded no premature UHI deaths, while urban heat was responsible for 32 premature deaths per 100,000 people in the Romanian city Cluj-Napoca.
The cities with the highest UHI death rates were in southern and eastern Europe. Most of these cities generally had low tree coverage and recorded the highest UHI effect.
Just 3.3% of Thessaloniki in Greece is covered by trees, resulting in urban temperatures 2.8? higher than the surrounding area. By contrast, 27% of Gothenburg is covered by trees, delivering an UHI effect of just 0.4?.
Overall, southern European cities will benefit most from increasing their tree cover. Our model estimates that Barcelona could reduce its UHI death rate by 60% by meeting the 30% tree coverage target.
Global warming is bringing more intense heat waves to our urban environments which means cities will need to adapt to the new temperatures. Indeed, regular readers will recognize a lot of ways cities can mitigate extreme heat from painting roads white to regulating green roofs. Over at Arch Daily they have compiled a neat list of good ways cities are exploring to stay cool.
The standard North American home (pictured above) is horrible inefficient and quite bad for the environment. As the climate crisis conies to worsen we need to change the way we provide shelter for people: and that’s exactly what Phoenix, Arizona did. Arizona is experience such extreme heat that everyday objects are melting and car tires explode, sometimes the airport can’t function either. This led the City of Phoenix to launch a competition for making the most affordable and environmentally friendly home.
The winning home building plan is available for free online from the city, meaning you can download a home.
The winner of the contest, Marlene Imirzian & Associates Architects, went even lower. The studioâ€™s affordable, three-bedroom home, dubbed HOME nz, has an impressive HERS rating of zero. A $100,000 prize went to Imirzianâ€™s firm, and the design is now available for widespread use; the City of Phoenix has made the construction plans for HOME nz available for free to encourage the public to build more eco-friendly homes. â€œThe city of Phoenix has a very visionary sustainability director and department who are looking for leadership for built work in the Phoenix area,â€ says Imirzian. â€œ[The] goal was to show how simple moves could result in significant [environmental] changes.â€
Since Phoenixâ€™s dry, sun-bleached environment involves extreme heat, the design incorporates high-performance glass, which reduces heat transmission from outside, and retractable fabric screens for greater shade and passive cooling without the help of an AC unit. But HOME nz is a useful and applicable model no matter the climate. â€œIf the volume performs well in terms of the separation of the interior and exterior then no matter where you build your house, it will be managed optimally by what youâ€™re surrounding the house with,â€ notes Imirzian. â€œIt would do just as well in a very cold climate or [a place] where you need conditioning or heating.â€
The urban heating effect is a very real threat to how we cool our cities. The concentration of cement and machinery generates and stores a lot of heat that natural systems can’t see cool. Unless we purposefully design our cities to incorporate natural cooling techniques. The video above explores three ways that cities can start to cool their local environments.