Climate change is leading to warmer nights, which in turn is disrupting sleep, according to US researchers. The poor and elderly are most affected.
Climate change is keeping some of us awake at night – and not just metaphorically, writes the University of California San Diego. According to its recent study, warmer temperatures in 2050 could cost Americans millions of additional nights of insufficient sleep per year. That figure could rise by several hundred million more nights of lost sleep annually by 2099 if climate change is not addressed.
“Sleep has been well-established by other researchers as a critical component of human health. Too little sleep can make a person more susceptible to disease and chronic illness, and it can harm psychological well-being and cognitive functioning,” said lead researcher Nick Obradovich said. “
“What our study shows is not only that ambient temperature can play a role in disrupting sleep but also that climate change might make the situation worse by driving up rates of sleep loss.”
Obradovich was inspired to investigate the link between climate change and sleep after a heat wave hit San Diego in October 2015 – leading him and his fellow students to sleep poorly from the excessive heat.
The study’s main findings is that atypical increases in night-time temperatures by 1°C translate to three nights of insufficient sleep per 100 individuals per month.
In other words: one single month of nightly temperatures average 1°C higher than normal is equivalent to 9 million more nights of insufficient sleep in a month across the population of the US today, or 110 million extra nights of insufficient sleep annually.
The researchers found that those whose income is below USD 50,000 and those aged 65 and older are affected most severely.
Using climate projections for 2050 and 2099, the study found that warmer temperatures could cause six additional nights of insufficient sleep per 100 individuals by 2050 and approximately 14 extra nights per 100 by 2099.
While the study only looked at US data, Obradovich believes that the pattern could be extended to other countries. “One can imagine that in places that are warmer or poorer or both, what we’d find could be even worse.”