Adriana Zuniga-Teran works in the School of Geography, Development and the Environment and the Udall Center for Studies in Public Policy at the University of Arizona. His research is at the intersection of urban planning, sustainability, and environmental management, focusing on the transformation of urban infrastructure to environmentally-based solutions. Originally published on The Conversation.
Modern buildings often take electricity and air conditioning for granted. They often have glass facades and windows that cannot be opened. And if the power goes out for days during a heat wave, as happened in the Houston area in July 2024 after Hurricane Beryl, these structures can be tolerable.
However, for thousands of years, civilizations were able to shelter people in hot and dry places.
As an architect and researcher studying urban sustainability, I have explored the many strategies and lessons these ancient civilizations can offer to survive in extremely hot and dry conditions.
As global temperatures rise, studies show that dangerous heat waves like those in 2023 and 2024 will become more common, and strong storms may cause more blackouts. To prepare for an even hotter future, designers today can learn from the past.
The Sumerians: Keeping It Cool Together
The Sumerians lived about 6,000 years ago in the hot and dry area of what is now southern Iraq. Even then, they had heat control techniques.
Archaeologists studying the remains of Mesopotamian cities describe how Sumerian buildings used thick walls and small windows to reduce exposure to heat and keep interior temperatures cool.
The Sumerians built their walls and roofs with materials such as adobe or mud that can absorb heat during the day and release it at night.
They also built buildings close to each other, which reduced the number of walls exposed to the strong rays of the sun. Small courtyards provided light and ventilation. The narrow streets ensured shade throughout the day and allowed pedestrians to move comfortably through the city.
Ancient Egyptians: Binding the Spirit
Ancient Egyptians also used things that could help with heat. The palaces were built of stone and had courtyards. The residential buildings were made of mud bricks.
Many people also started moving around their buildings to escape the heat: They used the roof terraces, which were cool at night, as a place to sleep.
To cool the buildings, the Egyptians developed a unique technology called mulqaf, which consists of long holes facing the prevailing wind. These vents act as spaces to capture air and send it down to help cool the building. The incoming air creates air circulation that helps remove heat from the other vents.
The mulqaf principle can also be extended to cool in larger spaces. Known as an air conditioner, it is currently used in buildings in the Middle East and Central Asia, making them comfortable without air conditioning, even in very hot weather.
Ancient Puebloans: Working with the Sun
Civilizations on other continents and at other times developed similar strategies for living in hot and dry environments, and developed their own unique solutions.
Puebloans in what is now the US Southwest used small windows, materials such as mud brick and stone, and designed buildings with partition walls to reduce heat gain.
The Puebloan cliff dwellings on Mesa Verde provided protection from the elements and, because of their position, were protected from direct sunlight in the summer. Andreas F. Borchert, CC BY-SA
They also understood the importance of the position of the sun. The ancient Puebloans built whole communities at the base of the south-facing cliffs. This orientation ensured that their buildings were shaded and kept cool during the summer but received sunlight and heat that radiated heat to stay warm in the winter.
Their descendants adopted the same orientation and other urban planning techniques, and adobe homes are still common in the US Southwest.
Muslim Caliphs: Using Every Drop of Rain Where It Falls
Modern water management is also rarely designed for dry climates. Stormwater infrastructure is designed to drain stormwater away from the city as quickly as possible. However, those same cities must bring water and gardens to the people, sometimes from distant sources.
The landscaping of the Mosque of Cordoba, Spain, was designed to capture rainwater where it is needed for irrigation. Adriana Zuniga
During the 8th century, the Muslim caliphates in the arid regions of northern Africa and southern Spain designed their buildings in such a way as to collect rainwater to retain water. Rainwater runoff was collected from all roofs and directed to water sources. The slope of the roof and the floor of the yard directed the water to be used to irrigate the grassy areas of their yards.
Modern-day Mendoza, Argentina, uses this method to irrigate the plants and trees along its elegant city streets.
The Mayans and Teotihuacans: Capturing Rainwater Later
At the urban scale, people also collected and stored rainwater to withstand the dry season.
The ancient Teotihuacan city of Xochicalco and many Mayan cities in what is now Mexico and Central America used their towers, plazas and aqueducts to direct stormwater to large wells for future use. Plants were often used to help purify water.
Large pits like the one in Xochicalco, a Teotihuacan community in what is now Mexico, were used to collect and store rainwater. Adriana Zuniga
Scientists today are exploring ways to store good quality rainwater in India and other countries. Rainwater harvesting and green infrastructure are now seen as effective strategies to increase the city’s energy.
Making These Lessons Work
Each of these ancient traditions offers lessons on staying cool in hot, dry climates that modern designers can learn from today.
Some architects are already using them to develop designs. For example, buildings in the northern hemisphere can be oriented to maximize exposure to the south. South-facing windows combined with shading devices can help reduce the sun’s rays in the summer but allow the sun’s heat through in the winter. Harvesting rainwater and using it to irrigate gardens and grounds can help reduce water use, adapt to drought conditions and increase urban sustainability.
Retrofitting modern cities and their glass towers for better thermal management is not easy, but there are strategies that can be adapted to accommodate new designs for living better in a hot and dry environment and less dependent on constant summer weather. These ancient civilizations can teach us how.
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