Almost a third of the world’s land surface is classified as ‘arid’ and this area is expected to increase as climate change brings more frequent, extreme weather events, such as drought. There is a great need for innovative developments in this field. 

Al Bahar Towers in Abu Dhabi by Aedas Architects, which have a unique, dynamic shading system – a modular ‘Mashrabiya’ that opens and closes to provide self-shading as the sun moves around the building (image via archdaily).

A report by Arup, an independent firm of designers, planners, engineers, consultants and technical specialists working across every aspect of today’s built environment, warns that technologies of the last century, such as air conditioning, have allowed the “explosive but unsustainable growth” of arid cities.

At the same time the report warns that many cities are experiencing the Urban Heat Island Effect, where they become hotter than the surrounding rural areas. This, it says, is particularly impacting arid cities, increasing water use and reducing their ability to sustain existing standards of living.

Arup is calling on arid cities to move on from what it calls “a 1950s paradigm of city planning and design”, or face becoming increasingly less habitable as they become drier. The report urges cities to learn from innovative developments around the world, such as industrial-scale fog and dew harvesting and cooling pavements that can reduce ambient temperatures by up to 7 degrees.

The issue has been sharply brought into focus in recent months with Cape Town in South Africa experiencing its driest year on record in 2017 following extremely low rainfall in 2015 and 2016. Residents and businesses have been limited to just 13.2 gallons of municipal water usage per day, per person. To set that into context the average US citizen uses between 80 and 100 gallons of water per day.

The Arup report follows the Urban Oasis Experience – the 5th International Green Roof Congress 2018 held in Kuwait in February this year. It showcased some ground-breaking projects involving green roofs and living walls. The Congress was held at Al Shaheed Park in Kuwait City (photo), which consists of 310,000m2 of greenery – and almost 80,000m2 of green roof – one of the largest green roofs in the world. It also looked at a living wall project in Dubai and the new Stavros Niarchos Foundation Cultural Center (SNFCC) in Athens, Greece (photo), designed with a sustainable approach and including 25,568m2 of green roofs.