“The amount of heat gained by a Bedouin exposed to the hot desert is the same whether he wears a black or a white robe. The additional heat absorbed by the black robe was lost before it reached the skin.”
Bedouin robes, the scientists noted, are worn loose. Inside, the cooling happens by convection - either through a bellows action, as the robes flow in the wind, or by a chimney sort of effect, as air rises between robe and skin.
Thus it was conclusively demonstrated that, at least for Bedouin robes, black is as cool as any other colour.
https://www.theguardian.com/education/2006/aug/15/research.highereducation
But t shirts don’t work like Bedouin robes.
So white and yellow for staying cool, every other color heats up.
Tradeoff is dark colors absorb more UV so it provides better protection from the sun
Umm…
Reflection is just as effective as absorption. As long as the UV isn’t passing through the fabric into you, you are fine.Well butter my biscuit, I might be wrong. There are other of factors to take into account, but it makes sense that, the portion of light that does make it through a light fabric will keep on reflecting inside the garment until it is absorbed or escapes back out. Like a photography light box.
Skincancer.org is my source for darker colors being better protection
I don’t have the highest degree of confidence in it but it makes sense to me that absorption matters more than reflection because a lot of the reflected UV will be going through the shirt and onto your skin
That’s why materials like linen aren’t as good for UV protection. They’re light weaves and let a lot of light through, still
Look at the sun through a white shirt, then black. Which is brighter?
The white would be as it would absorb (then converted to heat) less light and would reflect it instead.
Thebottom half is highlighting the absorption by showing radiance (giving off it’s own/stored energy), not reflection.
Gotta get that UV colored tshirt :-)
FYI there are UV absorbant tshirts, crazily practic for kids.
Red looks surprisingly effective as well.
Its a bit misleading. Black clothes will absorb the heat from the sun and your body and then the clothes will cool via convection. So the wind blowing through the clothes takes the heat away. White will reflect the heat from the sun away and your body back towards you.
Im sure theres some debate and probably way more to it but i have always felt more comfortable in the heat than other people and i wear darker clothes the majority of the time. If that anecdote bares any weight.
Are you telling me a human body is different from a manikan torso?
Seriously though, I think you’re onto something.
Google says : colors do not absorb different amounts of heat, only heat from light.
I just see that all colors turn into pride colors in the sun
Sun turns us gay!
Is there any way to tell the difference between infrared reflected between (I assume) 8 and 13 microns and the infrared emitted due to absorption of shorter wavelengths?
That’s not exactly heat absorbtion though. Infrared cameras capture the heat radiated by the shirts and black color is the one that radiates heat the best. That’s why matt black is the worst color for a thermos and chrome is the best.
If they have identical or close enough emissivity it is directly proportional to heat absorption, as given identical amounts of time in the sun and air flow, temperature will almost entirely depend in absorptivity, and emitted infrared is proportional to temperature^4.
Black bodies emit and absorb perfectly. These probably all have an emissivity that’s lower than a blackbody, and very close together, while absorptivity is related to the color of the shirt. So this test is actually fairly indicative.
Just get some loose linnen button down shirts, they are fantastic
What about sequined shirts? If I get the right angle I can boil a cup of water within seconds while staying cool inside. For an extra barrier I wrap my body in foil, keeps the 5g out as a bonus.
Also a good indicator of why must plants use chlorophyll, which primarily reflect green light in our planet’s biosphere.
I still can’t get myself to wear a white T-shirt despite me wanting it.
My sweat will ruin any white fabric after the first or second wear.
Do you use aluminum/antiperspirants? I think that is what causes the staining.
So does black make a significant difference when it’s colder? Or is it only noticable when there’s harsh sun?
As someone who grew up in northern areas, not really. In fall or spring (Oct, or April) when the sun has a better angle you can notice. But the rest of the winter when the sun’s at a slant? Not so much.
It’s different: radiation of long-wave infrared balanced against absorption of ambient light.
who would have guessed?
Well a dog. Could guess it I mean.
If dogs can guess things, which I don’t even know if they can. But maybe.
I think maybe a dog could guess it.
Dang green, you hot!
Also, grey… you have betrayed us.
How is a light gray that much warmer than yellow? Seems suspicious 🤔
I guess gray is just black and white mixed, and black does not do very well
Yellow also reflects a tonne of UV and IR light. Probably helps make it so much more visible to everything than other colors
Body puts off heat too. White reflects it back, black lets it escape.
Google says : colors do not absorb different amounts of heat, only heat from light.
