Do you find the incessant background music in stores and shopping malls distracting? Even annoying? Well, here's another reason not to like it: The malls of America consume more than a gigawatt of electricity per month playing the anodyne sales-spurring pop.

Enterprising Stanford students crunched the numbers on how much energy it takes to play all that pop and came up with a figure of 1.18 gigawatt-hours. Given the present energy mix that means Mantovani adds more than 3,000 metric tons of CO2 to the atmosphere each year.

To put that in perspective, the world as a whole emits roughly 30 gigatons of greenhouse gases per year. So mall music isn't exactly singlehandedly changing the Earth's climate. But malls do contribute an outsized portion of the heat-trapping gases from buildings, given their need for immense amounts of heating and cooling as well as always-on lighting.

In fact, temperature control and lighting account for more than 80 percent of a mall's energy consumption. Simply changing to more efficient light bulbs or HVAC systems would more than muffle the discordant thought of mall music's contribution to climate change.

—David Biello