Rising temperatures erode human sleep globally

Insufficient sleep is a risk factor for several adverse physical and mental outcomes. A lack of sleep has been associated with reduced cognitive performance, diminished productivity, compromised immune function, adverse cardiovascular outcomes, depression, anger, and suicidal behavior. High ambient temperatures have been associated with reduced subjective sleep quality, but little is known regarding the influence of outdoor weather conditions and rising outdoor temperatures on objective measures of sleep globally. When linked with global weather and climate measurements, sleep-tracking data from wristbands reveal that warmer nighttime temperatures do indeed harm sleep, with unequal effects. The elderly, residents of lower-income countries, females, and those already living in hotter climates are disproportionately impacted. Further analysis reveals that elevated ambient temperatures may already be impairing human sleep globally. Without further adaptation, and should greenhouse gas concentrations not be stabilized until the end of the century, each person could be subjected to an average of 2 weeks of temperature-attributed short sleep each year