Science·What on Earth?

Air conditioning in a warming world

In this week's issue of our environment newsletter, we look at how we cooled ourselves before air conditioning became used as much as it is today, and how artificial intelligence could help in the response to climate change.

Also: How artificial intelligence could help in the response to climate change

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(Sködt McNalty/CBC)

Hello, folks! This is our weekly newsletter on all things environmental, where we highlight trends and solutions that are moving us to a more sustainable world. (Sign up here to get it in your inbox every Thursday.)

This week:

  • Cold comfort: How we cooled ourselves before A/C
  • Which countries use air conditioning the most?
  • How AI could help us respond to climate change

Cold comfort: How we cooled ourselves before A/C


Roughly 2.8 billion people live in countries where the daily average temperature is 25 C, which is set to increase as the planet warms.

As a result of cheaper technology and a greater quality of life, more people will have access to air conditioners in the future. The International Energy Agency (IEA) estimates that by 2050, as much as two-thirds of the world's population could own an air conditioner.

This is both good and bad news. For one thing, it has literally saved lives. In 2013, an American study found that air conditioning had helped reduce the "mortality effect of an extremely hot day" by about 80 per cent between 1960 and 2004 compared to 1900 to 1959. A/C certainly makes people more comfortable during hot spells, but more cooling units put more stress on electricity grids, which in turn contributes to climate change.

While our grids are likely to become greener as we use renewables like solar and wind energy to replace fossil fuels like coal and natural gas, we can also become smarter in how we design buildings.

"From a technical perspective, pretty much anywhere in the world, you can build a building and not need air conditioning," said John Dulac, an energy consultant with the International Energy Agency. He said it depends "on how you design the building environment and the ventilation in the building."

Today, many of the office towers and condominiums we see are predominantly glass. This brings in more sunlight and therefore heat, which means a lot of electricity goes into cooling. Right now, a lot of buildings contain "thin walls, poor insulation, a lot of air gaps," said Dulac. "It's very hard to keep [buildings] cool." 

Even if we were to do so with greener energy, it would still be a waste of resources.

Dulac points out some older methods that can help us keep cool. For example, typically hot countries like Italy and Greece have used white roofs and lighter-coloured walls to resist the heat. 

In the past, homes also had higher ceilings that kept rooms cool. Windows were built with shutters that would keep direct sunlight out, saving the home from the punishing daytime heat in summer.

In the Middle East — no stranger to extreme heat — buildings were constructed based on the typical direction of the wind and available shade. Also, the placement of buildings was important: it was common to have a courtyard that maximized shade during the day and allowed heat to rise, which was in turn replaced by cooler air from surrounding rooms. These buildings didn't have many windows — just a couple to ensure air flow.

Dulac notes that it's difficult to retrofit existing buildings around the world with these concepts, especially since most people live in cities, where it's "cost-prohibitive to do those kinds of designs, and there's not a knowledge around it."

But since greater cooling is going to be a necessity, we might consider incorporating some of these older methods to keep us comfortable.

Nicole Mortillaro

(Thanks to reader Christina van der Wal Anonby for asking about this topic.)

Reader feedback

After our piece on air travel last week, reader Bernie Klassen wrote that Canadians "are all convinced that to see something different you have to travel the world! There are a million things in Canada that most people have never seen, and I have no need to leave this country until I've seen them all!"

Comments or suggestions? Write us at

Old issues of What on Earth? are here.

The Big Picture: Air conditioning use around the world

Air conditioning: For many of us, it makes summers bearable. As the world warms because of climate change, it's expected that more people around the globe will invest in these cooling units. A report released by the International Energy Agency last year said that the number of A/C units worldwide was expected to rise from 1.6 billion units in 2018 to to 5.6 billion units by 2050. Below is a sampling of countries and the percentage of their respective populations that own an A/C unit. Numero uno: Japan, with 91 per cent.

Hot and bothered: Provocative ideas from around the web

  • Farming practices — particularly meat production — have received a fair bit of criticism when it comes to emitting carbon, but Canadian farmers are playing a major role in mitigating climate change. One of the key strategies? Using the soil to capture carbon.

  • In a bid to make cities more livable, many urban planners have been pushing for increased green space. To wit, Montreal recently announced it is creating a 3,000-hectare park, which will be one of the largest of its kind in Canada. Mayor Valérie Plante said Grand parc de l'Ouest, as it will be called, will aid in wetland protection and become a natural barrier in the event of rising water levels.

  • Deforestation is a major issue when it comes to climate change, and until recently, Indonesia has been one of the worst offenders. But its president recently announced a permanent moratorium on new clearance in 66 million hectares of old-growth forest.

How AI could help us respond to climate change

(Ekaterina Anisimova/Getty Images)

Given the likelihood of higher temperatures and more extreme weather in our future, experts are searching for ways to sustain the planet. Some believe machine learning and artificial intelligence (AI) offer promising strategies to respond to the effects of climate change.

AI can work faster than a human, can forecast further into the future, has a low error rate and is available 24/7. Many people believe this allows it to better predict flooding, natural disasters and other destruction linked to climate change. 

And that's why in June, the University of Waterloo partnered with Microsoft AI for Earth. Launched in 2017, AI for Earth is a program that issues grants to projects using AI to address climate change challenges. It is dedicating $50 million US to this cause, and has given grants to more than 250 applicants in 66 countries.

The project focuses on finding solutions in four specific areas —  agriculture, water, biodiversity and climate change. 

The AI uses combinations of historical data, simulations and real-time satellite observations to track patterns much faster than a human being. This technology can better predict future events, including potentially forecasting the location of the next wildfire or using past data to improve food production through weather tracking and soil information.

Christopher Fletcher, associate professor at the University of Waterloo and grantee of the AI for Earth program, acknowledges there is fear of AI in some quarters. "I think most people think about AI as being a machine somehow replacing something that a human being does," Fletcher said. 

His project aims to use AI to predict future climate forecasts more accurately. "I have a machine that is able to kind of learn, but it's not replacing a human. It's actually replacing a more complicated computer model."

There are other commercially available projects, which focus on everything from creating sustainable, data-driven farming to analyzing blood from mosquitoes to stay ahead of diseases.

These applications could go some way in addressing climate change, but one analyst fears AI's success could dissuade people from altering their consumption habits, which contribute to environmental degradation.

"Although [AI] could be helpful for tracking things like overfishing or pollution, it takes people off the hook," said Kerry Bowmen, a bioethicist and conservationist. 

"Solving challenges like these doesn't make people change. This brings an issue of intergenerational ethics — we have a responsibility to future generations. We need more long-term solutions."

Taylor Logan

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Editor: Andre Mayer | Logo design: Sködt McNalty


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