In the colder months of winter, it is understandable to let global temperature rise and the risks of extreme heat temporarily slip our minds. In the Northern Hemisphere, October to May can often provide a welcomed respite, with the heat of summer becoming a distant memory.

However, we must recognize that this respite isn’t universal.

While things may feel cooler in places like San Francisco, Beijing, or Paris during the time those cities experience winter, rising temperatures remain a pressing global issue. It’s essential not to lose sight that when it’s winter in the North, it’s summer on the other side of the world.

Seasonable unpredictability

Not surprisingly, 2023 has been officially confirmed as the hottest year on record, with the boreal summer (June to August) being the hottest individual season, and by a significant margin. In fact, during this period, much of the Northern Hemisphere, including China, Europe, India, and the United States, experienced several extreme heat waves and record-breaking temperatures. With these events came numerous associated impacts, such as death, sickness, and income loss.

Even in the Southern Hemisphere, where it was the end of winter, extreme temperatures prevailed. In August and September, for example, temperatures soared above 104° F (40° C) across large parts of South America, setting a worrying precedent for what the austral summer (November to February) might have in store for the 850 million people — or 10% of the world’s population — who call the Southern Hemisphere home.

This warming trend continued into late 2023, with Brazil recording its hottest-ever temperature when the mercury hit 112.6° F (44.8° C) in November. These high temperatures led to red alerts for almost 3,000 towns and cities across the country and spikes in energy use as residents turned on their air conditioners to stay cool. It is estimated that more than 100 million people were affected by the heat during this period.

And now, in 2024, much of Australia has been battling “sweltering” temperatures above 86° F (30° C), increasing the risk of bushfires. In recent weeks, temperatures in the west of the country have climbed past 104° F. Several countries across Africa and Southeast Asia have also experienced well above-average temperatures over the last month or so.

Overall, around 80% of the world’s population was exposed to “unusual warmth” due to climate change between December 2023 and February 2024.

One of the most worrying aspects of this problem is that scientists predict that these record-breaking temperatures will continue over the coming years due to a combination of the El Niño effect and climate change-driven temperature rise. In fact, the Southern Hemisphere summer of 2024-25 is on track to bear the brunt of these impacts.

Cooling for climate resilience

To cope with rising temperatures — in both hemispheres — billions of people are expected to turn to air conditioning over the coming decades (if they can afford to), with an additional 3 billion AC units projected to be installed worldwide by 2050. Without action, a significant rise in global energy demand and greenhouse gas emissions will accompany the installation of these appliances.

For the billions of people who cannot afford air conditioning, a warmer world presents many risks to their health, well-being, and livelihoods.

To ensure resilience during periods of extreme heat, we must invest in the widespread adoption of energy-efficient, climate-friendly, and affordable cooling solutions. Not only will this ensure that no one is left behind, but it will also minimize the impact staying cool has on our planet and its climate.

In Australia — where heat contributed to the deaths of more than 36,000 people between 2006 and 2007 — a number of actions are being taken to boost resilience. In Sydney, for example, researchers launched mobile cooling hubs to help protect the city’s homeless communities during February’s extreme heat. Australia’s Bureau of Meteorology recently introduced a heatwave warning system, and its state and local governments are investing in nature-based solutions to mitigate urban heat islands. NGOs are also pushing for policies to improve construction codes to ensure more resilient buildings.

In Indonesia, CCC implementing partner Cool Roofs Indonesia is working to expand access to reflective cool roof materials to boost the resilience of low-income housing. Under the Million Cool Roofs Challenge, Cool Roofs Indonesia found that cool roofs could reduce indoor temperatures by up to 10° C (18° F).

Global action

While some countries have a bigger role to play than others, combating the cooling challenge requires global action. The pathway to a cooler future for all is clear, but it requires all stakeholders to get involved.

We must scale up the adoption of passive cooling solutions, dramatically improve the efficiency and grid-friendliness of our cooling technologies, and accelerate our transition to refrigerants with low global warming potential (GWP). Taking such action could result in a 60% reduction in cooling-related emissions by 2050. Decarbonizing our power grids could increase this to 96%.

To encourage the worldwide implementation of these efforts, the Cool Coalition and its partners have developed the Global Cooling Pledge — a set of commitments that countries can make to improve access to cooling while cutting emissions.

Since its launch at COP28, 70 national governments (and multiple other stakeholders) have rallied around the pledge. In the Southern Hemisphere, signatories include some 16 countries, indicating the region’s commitment to action on cooling — from both a mitigation and adaptation point of view.

As one season moves to the next, those in the Southern Hemisphere prepare for the cool of autumn and winter, while billions in the Northern Hemisphere anticipate what this spring and summer may have in store.

However, no matter where you live, temperatures are rising, and heat waves are becoming more frequent, more intense, and longer. We must take urgent action to boost cooling access and reduce cooling-related emissions.

Efficient, climate-friendly cooling for all is critical.