Experts agree that humans can live comfortably only in the temperate climate zone, a surprisingly narrow Goldilocks range between 17 and 24 degrees Celsius. This presents us with a problem as climate change increases summer temperatures alarmingly, causing record heat waves around the world.
Already, about 12 percent of the Earth’s land area is uninhabitable due to extreme weather conditions. This is expected to increase to more than 45 percent by the year 2100, and at least 44 percent of the world’s population is likely to have chronic depression. The World Health Organization estimates that between 2000 and 2019, there were 489,000 heat-related deaths – 45 percent in Asia and 36 percent in Europe.
In perspective, that’s a small number compared to the estimated 4.6 million annual deaths from colds. But heat deaths are expected to increase rapidly, and hundreds of cities could be unlivable by the end of the century. This brings us to the big challenge of staying cool wherever we live on the planet and, in more general terms, cooling space, which includes refrigeration.
As Europeans – who usually expect summer temperatures below those we endure in Hong Kong – have slowed down in recent weeks as temperatures rise. 40 degrees CelsiusThis focuses on the year of record heat, record heat deaths and questions about why Europe has very little air conditioning.
To be fair, we don’t rely on air conditioning alone to keep cool. Egyptians thousands of years ago hung soaked reeds in their windows to cool their homes. And the Romans ran aqueducts in their walls to achieve the same effect. Cities like Seville in southern Spain, which can see temperatures approaching 50 degrees Celsius, have built narrow streets, small shaded squares, fountains and planted shade trees to keep the heat down. And siestas are still a common practice to push work hours into the chilly evening hours.
Yet air conditioning, for those who can afford it, has played a major role in making life bearable in the world’s most tropical climate.
