Night Time Heat Is Dangerous And Affects People’s Sleep

Oppressive heat during the daytime brings discomfort to people, but scientists also warned that nighttime heat can be dangerous to the public. How is this so?

Columbia University's Data Science Institute postdoctoral research scientist Kelton Minor said in a CNN report that most people do not realize that "hot nighttime temperatures have been outpacing daytime temperature increases across most populated regions worldwide in recent decades."

As the days become warmer, more air moisture traps the heat, the CNN report disclosed.

Heat trapped during night time

The Medical Society Consortium on Climate and Health explained that during the day, that moisture reflects the heat, but at night, it traps the heat in.

Cities experience increasing nighttime heat because of the urban heat island effect in which metro regions are much hotter than their surroundings, the report explained.

Places with concrete, buildings, asphalt, and freeways absorb more heat from the sun than areas with parks, rivers, and streets surrounded by trees.

At night, the trapped heat is released back into the air.

According to Kristie Ebi, a climate and health expert at the University of Washington, places with green space are cooler on summer's hottest days.

She added that city officials should consider urban planning to counter the effects of climate change.

"It's going to take a while for trees to grow, but we need tree-planting programs focusing on places that are particularly vulnerable, making sure that city planning takes into account that we're heading into a much warmer future," Ebi told CNN.

In the 2018 National Climate Assessment, nights are warming faster than days in most part of the United States.

Experts said that this are one of the consequences of the climate crisis.

Climate Change Affects People's Sleep

In a recent study that was published last May in the journal One Earth, it was indicated that climate change has an impact on people's ability to sleep.

A person may lose 50 to 58 hours of sleep annually due to rising temperatures by 2099, with each person experiencing two weeks of lost sleep annually.

"Our results demonstrate that temperature-driven sleep loss likely has and may continue to exacerbate global environmental inequalities," the researchers said, as reported by Smithsonian Magazine.

Meanwhile, Medical Consortium on Climate and Health executive director Lisa Patel said in a CNN report that people know the discomfort in sleeping on a hot night.

"We often lose sleep. It is estimated that by the end of the century, we could lose about two days of sleep per year, and it will be worse for people without access to air conditioning," Patel said.

Patel added that heat stress could lead to heat stroke, which could be associated with confusion, dizziness, and passing out.

Experts have also found out that people around the world are already losing roughly 44 hours of sleep every year on average because of the warm nighttime temperatures during just the first part of the 21st century.

Minor said this observation was called as the "sleep erosion," adding that each person may lose up to 58 hours of sleep by the end of the century.

"People in our study did not appear to make up for lost sleep on hotter nights by napping during the day or by sleeping more during the days or weeks after. In fact, they lost additional sleep over these periods due to a delayed temperature effect, possibly due to ambient heat being trapped indoors," said Minor.

Meanwhile, studies also found that heat wave could lead to death as the body cannot keep itself cool.

According to a 2022 study published in Communications Earth & Environment, the climate crisis is expected to increase exposure to dangerous heat index levels by 50% to 100% in much of the tropics and by up to 10 times across much of the globe unless planet-warming pollution is reduced, the Digital Journal reported.