Air Conditioning Saves Lives but Deepens Climate Crisis, Experts Warn

As global temperatures climb, air conditioning has become a critical tool for survival, yet its widespread use is accelerating the very warming that makes it necessary. A new study published in Nature Health reveals that air conditioning saved nearly 58,000 lives in the United States between 2010 and 2020, an average of more than 5,000 lives per year.

The research, which analyzed 30 million death records, found the greatest life-saving impact in hot-weather states like Arizona, Florida, Texas, and Louisiana. However, the study's senior author, Yale School of Public Health professor Kai Chen, warns that the benefits come with a significant environmental cost. "Everyone knows air conditioning works, but air conditioning from a climate change perspective is not an ideal," Chen said. "It leads to more carbon emissions... then it accelerates the climate warming problem."

The scale of the challenge is immense. The International Energy Agency (IEA) and the United Nations Environment Programme (UNEP) project that electricity demand for cooling will triple globally. The UN estimates that greenhouse gas emissions from air conditioning could rise from 4.5 billion to 7.2 billion tons in the next 25 years—a figure nearly matching the current combined carbon output of the US and Europe.

In response, some nations are taking action. Eight countries, including Bangladesh, Cambodia, and Singapore, have imposed limits on how cool air conditioners can be set in offices. India proposed similar restrictions in 2025. Meanwhile, experts from 75 countries are set to meet in Singapore in September under the Global Cooling Pledge to balance heat-related deaths with climate goals.

Chen's research also highlights the problem of overuse, noting that more than half of the cases studied involved excessive cooling. He suggests 75 degrees Fahrenheit (24 degrees Celsius) as a reasonable limit. "Using more air conditioning than needed doesn't save more lives, but it does worsen climate change," he added.

The issue is also one of equity. UNEP officials note that many vulnerable populations cannot afford cooling. "In a warming world, thermal comfort should not be a luxury," said Eleni Myrivili, UNEP's chief heat officer. "It's becoming a prerequisite for health, dignity and increasingly survival."

Experts advocate for "smarter and more equitable cooling" rather than less cooling. Singapore serves as a model, using urban greenery and efficient building systems to reduce energy costs by $35 million annually and lower temperatures in some areas by 8 degrees Celsius. However, officials acknowledge that in extreme heat and humidity, air conditioning remains indispensable.