Eddie Cochran had it all wrong. Who would want to cure the summertime blues? On the contrary: Blues are the cure for summertime.

Or at least for those days when summer, wonderful as it mostly is, gets to be too much: when your car is an oven, when the air ripples up from the pavement on the highway, when the sun’s glare in the evening rush hour feels like it’s frying your corneas.

That’s when blue — a lake, sky, dusk — becomes summer’s antidote: the optical equivalent of putting your face in front of the air conditioner and cranking it up full blast.

It’s no coincidence that swimming pools are painted that inviting azure.

The color blue is relatively scarce in nature if you don’t count the oceans, which cover 70 percent of the Earth, making the planet a blue marble when seen from space. Or the sky, which — in case a 5-year-old ever asks you — is blue because of the way the color’s light wavelengths bounce off gas molecules in the atmosphere.

But among mammals, blue pigmentation is rare. There are various explanations. Want a technical one? According to a 2004 article in the Journal of Biological Chemistry, “to appear blue a compound must contain an extended and usually highly polarized system of the conjugated π-electrons.” Well, of course! A simpler way to explain it is that in most terrestrial environments, blue stands out, making it ineffective as camouflage. Blue coloration is more common among birds and sea creatures, exceptions that would seem to prove the rule.

Maybe its rarity is why people are most likely to pick blue as their favorite color (green runs a distant second). Or maybe that’s because our ancient ancestors associated it with clear skies and clean water.

If you really love blue, just wait a few months and the color will be all over the place in the form of shadows on snow (blue because the snow’s icy crystals reflect the sky). By the time you’re done shoveling, the reds and yellows of a roaring hearth will probably look mighty appealing.