A cool guide to heat absorption between different colored T-shirts
A cool guide to heat absorption between different colored T-shirts
"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.
Only if you don't know how to sandwalk, Outworlder.
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.
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.
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.
Dang green, you hot!
Also, grey... you have betrayed us.
So I saw this yesterday and I can't stop seeing things that may relate because green.
Just get some loose linnen button down shirts, they are fantastic
my friends make fun of me for wearing black in the summertime but i am more uncomfortable wearing non-black than i am just sweating it out 🫠
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.
So does black make a significant difference when it's colder? Or is it only noticable when there's harsh sun?
It's different: radiation of long-wave infrared balanced against absorption of ambient light.
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.
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.
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.
The temperature of the shirt itself will have a majority of the impact on the heat transfer. Whether a given pigment is reflective in the ir is impossible to predict by eye, see below. Black shirts will warm you up more in general, though offer better protection against UV. You can however get special UV protective white colored shirts.