Heatwaves : deadly for older adults
A deadly heatwave gripped large regions of Asia for weeks in April and May 2024. As temperatures soared past 43.3 degrees Celsius in India on May 7, campaigning politicians, local news announcers, and voters waiting in long lines fainted from the oppressive heat.
From as far north as Japan to as far south as the Philippines, the relentless heat wreaked havoc on daily life. In Cambodia, students and teachers were sent home from school as their hand-held fans provided little relief against the stifling heat and humidity in poorly ventilated classrooms. Farmers in Thailand watched their crops wither and mourned the loss of livestock that succumbed to the punishing sun. Hundreds of people died from the heat.
Most of the planet has suffered the dire effects of extreme heat in recent years.
A weeks-long heatwave in the southwestern United States in 2023 was described as “hell on earth” in one city, where temperatures reached 43.3 degrees Celsius or higher for 31 consecutive days. At the same time, Europe experienced unprecedented high temperatures that killed hundreds and contributed to devastating wildfires in Greece.
Regardless of where or when a heatwave strikes, one pattern remains constant: older adults are the most likely to die from extreme heat, and this crisis is expected to worsen in the coming years. As researchers studying climate change and population aging, we document two global trends that together foretell a dire future.
First, temperatures are hotter than ever. The nine-year period from 2015 to 2023 recorded the highest average temperatures since global records began in 1880.
Second, the global population is aging. By 2050, the number of people aged 60 and older will double to nearly 2.1 billion, making up 21 percent of the global population, compared to 13 percent today.
These combined trends mean that an increasing number of vulnerable older adults will be exposed to intensifying heat.
To understand the future risks, we developed population projections for different age groups and combined them with climate change scenarios for the coming decades. Our analyses show that by 2050, more than 23 percent of the world population aged 69 and older will be living in regions where peak temperatures routinely exceed 37.5 degrees Celsius, up from just 14 percent today.
Mapping the data reveals that most of these older adults reside in lower- and middle-income countries with insufficient services and limited access to electricity, cooling appliances, and safe water.
In historically cooler regions of the Global North, including North America and Europe, rising temperatures will be the primary factor driving older adults’ heat exposure. Conversely, in historically hotter regions of the Global South, such as Asia, Africa, and South America, population growth and increases in longevity mean that rapidly increasing numbers of older adults will face intensifying heat-related risks.
Policymakers, communities, families, and older residents themselves must understand these risks and be prepared, given older adults’ heightened vulnerability to heat.