Nighttime Temps Rising Faster Than Daytime Temps

Nights Are Warming Faster Than Days. Here’s Why That’s Dangerous.

1920  1940  1960  1980  2000         1920  1940  1960  1980  2000

Nationwide, summer nights have warmed at nearly twice the rate of days, with overnight low temperatures increasing 1.4 degrees Fahrenheit per century since 1895, when national temperature records began, compared to a daytime high increase of 0.7 degrees per century. (Nights have warmed faster than days during other seasons, too.)

 As you can see from the plot, what appears to be small increases in global temperatures, 1.4 degrees Fahrenheit since 1895, has large consequences to weather.

In a typical year, heat waves kill more Americans than any other natural disaster including floods, tornadoes and hurricanes.

While warm summer nights may seem less concerning than scorching afternoons, “the combination of high daytime and high nighttime temperatures can be really lethal because the body doesn’t have a chance to cool down during the nighttime hours,” said Lara Cushing, professor of environmental epidemiology at San Francisco State University.

As our planet warms, air conditioning to which people will resort, will only make things worse.

While air conditioning can provide a respite from intense heat, it isn’t a panacea. Air conditioners work by sending hot air outside, adding to the heat island effect. If fossil fuels are used to provide power for air conditioners, it exacerbates climate change. And, increased air conditioner use taxes electrical grids making power failures more likely. In the midst of the recent heatwave, roughly 90,000 Los Angeles area residents lost power because transformers, which help distribute electricity, overheated and failed.

Health officials in Canada estimated that up to 70 people in Quebec may have died from heat-related causes after a July heat wave stretched north.