Hotter nights are costing you sleep: Here's how much
The benefits of good sleep
Most adults need 7 or more hours of quality sleep each night, according to the National Institutes of Health. Kids and teens need even more.
Hotter nights are making it increasingly difficult for people around the world to get a good night's sleep, according to a new analysis from Climate Central.
The nonprofit organization analyzed 1,338 cities worldwide, including 253 in the United States.
To estimate how climate change is affecting sleep in cities globally, Climate Central applied an established relationship between nighttime temperature and sleep to both observed and counterfactual temperatures — or the temperatures that would have occurred in a world without carbon pollution.
The organization analyzed two time periods: 2020 to 2025, and a historical period in the early 1970s. This allowed researchers to estimate how much sleep the average person lost due to high nighttime temperatures and how much of this sleep loss was due to climate change.
Person loses sleep each year due to nighttime temperatures
Big picture view:
According to the analysis, the average person lost nearly 56 hours of sleep each year because of high nighttime temperatures during the 2020 and 2025 period.
Climate Central found the average person lost nearly 56 hours of sleep per year due to high nighttime temperatures from 2020-2025. (Credit: Getty Images)
The report found that between 2020 and 2025, about six of those lost hours – just over 10% – were directly attributable to human-caused climate change.
In fact, across nearly every city analyzed, the amount of temperature-related sleep loss linked to climate change has at least doubled since the early 1970s.
What they're saying:
"Sleep plays a crucial role in human health and well-being," the report said, noting that poor sleep has been linked to mood disorders, reduced cognitive performance, lower productivity, and increased risks for cardiovascular and immune-related health problems.
Middle East experiences greatest climate-related sleep loss
Local perspective:
The report also found that the impacts were not evenly distributed.
Cities across the Middle East experienced the greatest climate change-related sleep losses during the study period.
Residents in cities across Saudi Arabia, Oman and the United Arab Emirates lost an estimated 55 to 87 hours of sleep annually because of hot nights, including 12 to 16 hours directly linked to climate change – nearly two full nights of sleep each year.
Other regions experiencing substantial climate-related sleep loss included southern India, Southeast Asia and parts of West Africa, where people lost up to 91 hours of sleep annually because of elevated nighttime temperatures.
Meanwhile, in the United States, people lost an average of 36 hours of sleep each year because of hot nights between 2020 and 2025. About four of those hours, or 13%, were attributed to climate change. The largest climate-related sleep losses occurred in cities across Arizona, California, Florida and Nevada, where residents lost between seven and nine hours of sleep annually due to warming linked to climate change.
Sleep loss has increased over time
Dig deeper:
The analysis also found that climate change's role in sleep disruption has increased dramatically over time.
Globally, climate change-related sleep loss has roughly doubled since the early 1970s, rising from about two hours per year to about five hours annually. Among the 1,338 cities studied, the climate change-related portion of sleep loss at least doubled in all but three cities and at least tripled in 840 cities.
In U.S. cities, climate-related sleep loss has grown even faster, roughly tripling from just over one hour annually in the early 1970s to about four hours today.
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Scientists note that while air conditioning can reduce the effects of hot nights, it is not a complete solution. Access to cooling is closely tied to income, and many households worldwide still lack air conditioning. Even in places where air conditioning is common, hotter nights can continue to reduce sleep quality.
The report also found that some populations are especially vulnerable. Previous research cited in the analysis showed that adults over age 65 experience more than twice the sleep disruption from warm nights as middle-aged adults. Women, people living in lower-middle-income countries and residents of already hot climates also face greater impacts.
The Source: The information for this story was provided by Climate Central. This story was reported from Los Angeles.