New nightmare formany: Hot nights that mean lost sleep

Climate change is even getting in the way of a decent night’s sleep. Higher nighttime temperatures are disrupting sleep patterns, a new study finds, with more sleep lost in the summer and among elderly and lower- income Americans.

It’s the largest real- world study yet to link lack of sleep and unusually warm nighttime temperatures and the first to look at what that means if global warming remains unchecked.

“We found that unusually warm nights are associated with increased reports of nights of insufficient sleep,” said study lead author Nick Obradovich, who conducted much of the research as a doctoral student at the University of California- San Diego.

In October 2015, an unusual heat wave hit San Diego, where not everyone has air conditioning. Obradovich and colleague Robyn Migliorini noticed “friends and colleagues in grad school weren’t sleeping well at night — sheets off, tossing and turning in the heat — and as a result people were lethargic and somewhat grumpy,” he said. “It was pretty unpleasant.”

Spurred on by that experience, Obradovich found that no one had studied sleep disruptions as a potential impact of climate change.

Researchers collected sleep data from 765,000 U. S. residents and compared the nights they reported trouble sleeping to temperature data from the National Oceanic and Atmospheric Administration. The study, published in the journal

Science Advances, found that unusually warm weather led to three nights of poor sleep per 100 people per month.

Lower- income people suffered more sleep loss because they face tighter budgets than high- income individuals.

“Running the air conditioning all night can be costly,” Obradovich said.