Generally in summer, we’re treated to lines of loose summery white clothing. Not only is the white supposed to look nice floating around the edges of a picnic — until a few seconds into the event, when it has its first grass stain — people claim that white is the ideal way to keep cool in the summer. When we see white, we’re seeing the combination of all possible visible light. This means that white clothing reflects a great deal of wavelengths of energy coming in. This means it should reflect the sun’s rays back, instead of letting them cook us. And that’s perfectly correct.
Except that this explanation is also incomplete. Heat is not just coming in off of the sun. It’s also coming off a person’s own, sweating, warm-blooded, mammalian body, which is a lot closer than the sun is. When all that body heat hits the white clothing covering it, it gets reflected right back towards the body. When we wear white, we cook ourselves.
The best color to keep cool in the heat, it turns out, is to wear black. Black absorbs everything coming in from the sun, sure. But black also absorbs energy from the body instead of reflecting it back. Now, the helpfulness of black clothes depends on finding black clothes that are the same thickness and looseness as those summery white clothes. Black clothing also needs a little help from atmospheric conditions. Once it has absorbed heat, it has to have some way to radiate it away. If there’s even a little wind, black clothing is the better choice for those who want to keep cool, like goths who understandably don’t like sweating through their make-up. So find something black to wear this summer.