Ancient civilizations knew how to keep cool in deadly heat. We need to resurrect that lost knowledge now.

Modern buildings tend to take electricity and air conditioning for granted. They often have glass facades and windows that can't be opened. And when the power goes out for days in the middle of a heat wave, as the Houston area experienced in July 2024 after Hurricane Beryl, these buildings can become unbearable.

Yet, for millennia, civilizations knew how to shelter humans in hot and dry climates.

As an architectural designer and researcher studying urban resilience, I have examined many of the techniques and the lessons these ancient civilizations can offer for living in hotter and drier conditions.

With global temperatures rising, studies show that dangerously hot summers like those in 2023 and 2024 will become increasingly common, and intense storms might result in more power outages. To prepare for an even hotter future, designers today could learn from the past.

Related: People are getting 2nd-degree burns from sidewalks

Sumerians: Keeping cool together

The Sumerians lived about 6,000 years ago in a hot and dry climate that is now southern Iraq. Even then, they had techniques for managing the heat.

Archaeologists studying remnants of Mesopotamian cities describe how Sumerian buildings used thick walls and small windows that could minimize heat exposure and keep indoor temperatures cool.