Climate change likely to reduce the amount of sleep that peo
Most research looking at the impact of climate change on human life has focused on how extreme weather events affect economic and societal health outcomes on a broad scale. Yet climate change may also have a strong influence on fundamental daily human activities—including a host of behavioral, psychological, and physiological outcomes that are essential to well-being.

The investigators report that increasing ambient temperatures negatively impact human sleep around the globe. The team says their findings suggest that by the year 2099, suboptimal temperatures may erode 50 to 58 hours of sleep per person per year. In addition, they found that the temperature effect on sleep loss is substantially larger for residents from lower income countries as well as in older adults and females.

The investigators used anonymized global sleep data collected from accelerometer-based sleep-tracking wristbands. The data included 7 million nightly sleep records from more than 47,000 adults across 68 countries spanning all continents except for Antarctica. Measures from the type of wristbands used in this study had previously been shown to align with independent measures of wakefulness and sleep. The study suggested that on very warm nights (greater than 30 degrees Celsius, or 86 degrees Fahrenheit), sleep declines an average of just over 14 minutes. The likelihood of getting less than seven hours of sleep also increases as temperatures rise.