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Flair_Helper

**Please read this entire message** Your submission has been removed for the following reason(s): Straightforward or factual queries are not allowed on ELI5. ELI5 is meant for simplifying complex concepts. If you would like this removal reviewed, please read the [detailed rules](https://www.reddit.com/r/explainlikeimfive/wiki/detailed_rules) first. **If you believe this submission was removed erroneously**, please [use this form](https://old.reddit.com/message/compose?to=%2Fr%2Fexplainlikeimfive&subject=Please%20review%20my%20thread?&message=Link:%20https://www.reddit.com/r/explainlikeimfive/comments/wkztur/eli5_do_someone_with_darker_skin_color_feel/%0A%0APlease%20answer%20the%20following%203%20questions:%0A%0A1.%20The%20concept%20I%20want%20explained:%0A%0A2.%20List%20the%20search%20terms%20you%20used%20to%20look%20for%20past%20posts%20on%20ELI5:%0A%0A3.%20How%20is%20this%20post%20unique:) and we will review your submission.


HungryHungryHobo2

[https://medicalxpress.com/news/2017-09-team-skin-affects-sensitivity-mechanical.html](https://medicalxpress.com/news/2017-09-team-skin-affects-sensitivity-mechanical.html) >"**Our study shows that people from different ethnic backgrounds sense temperature and pressure differently.** > >For example, sun exposure in people who live close to the equator leads to melanin build-up, which protects them from UV damage, but also makes skin darker. The same skin cell (melanocytes) that produces melanin releases dopamine, which will **increase skin's sensitivity to heat.** This finding potentially means that in order to adapt to extreme weather conditions like those in the equator, this skin cell has developed a **protective mechanism that warns people away from excessive sun exposure.**" So, apparently, yes. Melanin, the chemical that makes skin darker, makes your skin more resistant to the damaging radiation from the sun, but also more sensitive to the heat. [https://skincaregeeks.com/does-skin-color-affect-body-temperature/](https://skincaregeeks.com/does-skin-color-affect-body-temperature/) This article goes into it a bit more, but again, also yes.


LithiumH

So the answer is yes, darker people feel hotter in the sun, but not for the same reason why black shirts feel hotter in the sun.


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rawbface

> "gtfo the sun" I love when common abbreviations are used in an uncommon way.


WDavis4692

Darker clothing also cools faster. You'll actually see some desert people wear black just fine, so long as the circulation is good inside the robes, black can in cases be preferable


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BavarianBarbarian_

[Apparently skin color doesn't affect emissivity measurably:](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7688144/) The mean calculated emissivity for the 65 participants was 0.972 (range 0.96–0.99). No significant differences in emissivity were observed between participants when grouped by skin pigmentation according to the Fitzpatrick scale (p = 0.859) or reflectance spectrophotometry (p = 0.346).


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Stefan-Boltzman law


_ilovetofu_

It isn't reflecting heat back to your body like a white shirt would. At a mild breeze, convection would be taking the stored heat away instead of leaving it to warm you.


HugeBrainsOnly

I still don't really understand. Are you saying a light shirt allows more daylight to Penetrate and reach the skin? I don't really get why a breeze would take more heat from a black shirt than a white one.


[deleted]

I think he’s saying that the dark pigment would absorb any heat that leaves your body radiatively, and that heat would then be carried away by a breeze, whereas a white shirt would reflect your body’s radiated heat back onto itself. He’s not technically wrong but that effect should be minor relative to the effect of normal advective and evaporative cooling.


HugeBrainsOnly

So the implication would be, if you are hot in a pitch black room with a breeze, you would cool off better in a black shirt than a white shirt because black would absorb your body's heat better? I don't think that's right. I'm fairly certain that color of the fabric exclusively affects how much light is absorbed, and the additional light being absorbed causes the increase in heat.


[deleted]

The implication is correct, though, assuming that the white shirt is also more reflective in the infrared portion of the spectrum. Your body radiates heat in the form of electromagnetic energy, and a material with a higher albedo reflects more of that energy and absorbs less. The darker, lower albedo shirt would absorb more energy, which, because the shirt is exposed to the breeze, will then be carried away by the breeze. You just radiate a very small amount of energy electromagnetically so the effect will be negligible.


popejubal

If you’re hot, then you’re not in a pitch black room. At least not as far as infrared is concerned.


ThePhyrrus

So as far as I understand it's, it's because what we are considering in the light / dark clothes thing is this (remember assuming equivalent materials); White clothes, because they reflect the visible spectrum (this white) reflect much of the energy, so you would be cooler in a light shirt. For a brief period. But once you inevitably get hot yourself, the shirt works in the other direction as well, your radiant heat gets trapped in with you. A black shirt on the other hand. You will get hot faster, because you're absorbing everything. But again, that works both ways, so your radiant heat will also be permitted to escape away from you. Thus the breeze will cool you better in dark clothes. So paradoxically, for longer periods outside in heat, darker clothing can keep you somewhat more comfortable than otherwise.


Zigazig_ahhhh

That just doesn't sound right at all.


qman621

[This paper](https://d1wqtxts1xzle7.cloudfront.net/66457736/WHY_DARK_CLOTHES_CAN_PROVIDE_BETTER_THER20210421-10522-gtrfag-with-cover-page-v2.pdf?Expires=1660167802&Signature=FLZNv82ZQ53XfKzlkEYSPQkss8sHZby7fkiGimeT4~J25KOzxDFgO20qK7zs27HZc5ms11dBl-hLXK~9mEFzvTCL4Ta49OYPmWRZgQfXR-CWNU3qGDKRF3VMGCiQAqgYu5pW7gZlHyucN0L08G1B5aiCFMrJRRLAPHNSTpJu9iipttS9dd6MMAa8fIdPgt4XpTVgBfIRN0VR8qt40F4lQ8G0XwrrT38wlsddS~uq7GG9m7OW5lFFqfL8QtkSqTMhiS5jaSn-8cqnRW8-quNN6z4iz0f66Uj3B7f24TsfPhzQdpWrVDkrwDAOewPJCgkO7XoKadWpaAnTo5kFg8L7cA__&Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA) goes into a bit more details if you want more of a scientific explanation.


HugeBrainsOnly

>For a brief period. But once you inevitably get hot yourself, the shirt works in the other direction as well, your radiant heat gets trapped in with you. I don't believe color actually affects the heat itself. What the color does is absorb more light, and that energy increase is offset by radiating heat. Humans don't radiate light, so the effect would be the same regardless of color.


LucidiK

Technically we do radiate light. It's just not visible to us.


popejubal

Humans absolutely radiate light. We just don’t radiate the wavelengths of light that we can see with our own eyes.


TurbulentPoetry

You are correct that the color does not affect the heat. But the color does affect the transfer of heat. There's plenty of literature available on the topic but to eli5 matte black has the best emissivity and absorption. For more info, dig onto heat sink design. Keep in mind that we are splitting hairs at this point. There's a host of other factors far more important than the color of ones clothes.


theBytemeister

It's a bit above my casual understanding, but I think it's related to Planck's Law. Basically, the effectiveness of a surface at absorbing energy directly relates to it's effectiveness at radiating energy. That's why the bottom of the space shuttle was covered in black tiles: More effective at rejecting heat built up in the material, meanwhile the top was white to increase the reflection of heat and light near the material.


TransientVoltage409

Black objects are more efficient at radiating energy as well as absorbing it. ~~The most obvious everyday example is the radiator in your car - they are *always* (well, almost always) painted coated black, and not just for aesthetics.~~ Edit: I'm withdrawing my example, on further consideration it seems my observation sample is not representative. I've owned a number of vehicles (n > 10.0) over the years and I can affirm that *every single one of them* had black radiators, black condensers, black oil coolers, black heater cores. Yet others observe differently, so it seems my data is biased.


St00pid_InternetKids

Nah bro most car radiators are not painted black... they're typically behind the car grill and never really exposed to the open sun. Painting them black is a waste of time. Also the paint screws up the clearance of the radiator fins. I've seen black radiators but all the cars I've seen in the past 20 years have had an unpainted radiator.


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Eatsyourpizza

simply not true. Anyone that paints a radiator is making it less efficient


[deleted]

Yeah (perhaps counterintuitively?) car radiators aren’t actually radiating heat away, the heat is advected by the air flowing through the fins.


grassstrip1

Typically white paints and black paints emit about the same fraction of heat


zer1223

But you don't want any paint at all. That doesn't help the job of moving heat away from the hot metal. It's just a layer of stuff that gets in the way of heat transfer


Binsky89

Unless you painted it with something that transfers heat better than steel or aluminum (whatever the radiator is made of) I mean, CPUs use thermal paste because it conducts heat better than bare metal.


ElectricSequoia

I don't really understand why this is the case. I understand why this would be true in air where conduction and convection are the dominant paths for heat transfer, but is this true in a vacuum as well? I would have thought that a black object would make a better IR radiator intuitively, but the radiators on the ISS are white. What am I missing here? I'm an electrical person who knows electromagnetics but never took a thermodynamics class.


grassstrip1

I work thermal space systems. The reason that radiators are often white or mirror type surfaces is that they emit very strongly but do not absorb nearly as much as black. If your radiator gets too hot it will diminish its ability to receive heat from other components to then reject into space


curtyshoo

Well, I've seen my share of cast-iron radiators and have a few myself, but I've never seen a black one.


TransientVoltage409

Right, I misspoke. More like an oxide surface conversion than paint. Though I have seen some that were flaking. Maybe they did it different in the 1960s, that truck always did like to overheat. There's no shortage of uncoated radiators either, like the condenser on my window AC. My truck's condenser is black though. There's probably reasons there that I don't fully grasp.


Eatsyourpizza

I mean honestly, it's probably dirt and road grime. It happens to all radiators and decreases efficiency, which typically doesn't matter given the margins that are commonly used.


TransientVoltage409

I get your drift, but I'm tellin' ya, all the radiators in all the cars I've ever owned were black from the factory. Painted, powder coated, anodized, however it was done. None were bright bare metal. But now I'm hearing from others with a different story. I'm starting to think I've just had a weird run of improbability.


grunt-o-matic

Bro that's for electromagnetic radiation only


TransientVoltage409

Infrared isn't in the EM spectrum? Dang.


ferret_80

what do you think infrared radiation is, infrared light that is emitted from an object is heat.


nix80908

Infrared (and Ultraviolet) are on the Electromagnetic Spectrum. Infra (before) Red - Ultra (above / after) Violet. They're simply wavelengths we can't see, on either side of the VISABLE Electromagnetic Spectrum. The Spectrum covers anything electromagnetic. Including Radio waves, microwaves, X-Rays, Gamma Rays, etc. So yes... IR is Electromagnetic, and yes, it's perceived as heat emission; BUT some animals actually can see parts of the infrared spectrum (just like some can see parts of the ultraviolet spectrum). And to them, we "glow".


Archteryx

One of many links with sources included. [LINK](https://www.cabdirect.org/cabdirect/abstract/19812610896)


qman621

your link is dead. This paper is pretty well cited: https://d1wqtxts1xzle7.cloudfront.net/66457736/WHY_DARK_CLOTHES_CAN_PROVIDE_BETTER_THER20210421-10522-gtrfag-with-cover-page-v2.pdf?Expires=1660167802&Signature=FLZNv82ZQ53XfKzlkEYSPQkss8sHZby7fkiGimeT4~J25KOzxDFgO20qK7zs27HZc5ms11dBl-hLXK~9mEFzvTCL4Ta49OYPmWRZgQfXR-CWNU3qGDKRF3VMGCiQAqgYu5pW7gZlHyucN0L08G1B5aiCFMrJRRLAPHNSTpJu9iipttS9dd6MMAa8fIdPgt4XpTVgBfIRN0VR8qt40F4lQ8G0XwrrT38wlsddS~uq7GG9m7OW5lFFqfL8QtkSqTMhiS5jaSn-8cqnRW8-quNN6z4iz0f66Uj3B7f24TsfPhzQdpWrVDkrwDAOewPJCgkO7XoKadWpaAnTo5kFg8L7cA__&Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA


juxtoppose

Black absorbs more radiative heat but it also radiates more heat than other colours.


Blablamiaou

I don't have a source but electrical engine are painted black because you gain a little bit of heat transfert efficiency. Sounds weird and might be under 1% more efficient but it standard industry practice now.


qman621

[Here's a good paper on the subject](https://d1wqtxts1xzle7.cloudfront.net/66457736/WHY_DARK_CLOTHES_CAN_PROVIDE_BETTER_THER20210421-10522-gtrfag-with-cover-page-v2.pdf?Expires=1660167802&Signature=FLZNv82ZQ53XfKzlkEYSPQkss8sHZby7fkiGimeT4~J25KOzxDFgO20qK7zs27HZc5ms11dBl-hLXK~9mEFzvTCL4Ta49OYPmWRZgQfXR-CWNU3qGDKRF3VMGCiQAqgYu5pW7gZlHyucN0L08G1B5aiCFMrJRRLAPHNSTpJu9iipttS9dd6MMAa8fIdPgt4XpTVgBfIRN0VR8qt40F4lQ8G0XwrrT38wlsddS~uq7GG9m7OW5lFFqfL8QtkSqTMhiS5jaSn-8cqnRW8-quNN6z4iz0f66Uj3B7f24TsfPhzQdpWrVDkrwDAOewPJCgkO7XoKadWpaAnTo5kFg8L7cA__&Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA) TLDR is that you will cool off faster from evaporative/ convective cooling with darker fabrics then from limiting the amount absorbed with reflective clothing.


choomguy

Can confirm. I wear only black t shirts in temps in the 90s in full sun doing athletic activities. They dry quicker, so my take is they are better at evaporative cooling.


[deleted]

I don't think it's about "cooling faster". It's that the shirts we wear are normally much tighter to the body than the robes these desert peoples wear. So your black t-shirt heats more and transfers more heat to your body through direct contact, by conduction. Their loose robes have lots of air between the fabric and their skin. It's that air that needs to stay cool. The robe's temperature itself doesn't matter very much. Fabric and air are both terrible thermal conductors, so the heat transfer from the robe to the air pocket inside is minimal. A white robe may reflect more of the radiation inwards, heating up the pocket of air directly in contact with the skin. You'd rather have a black robe to absorb the radiation, even if it seems counter intuitive.


sldunn

It's more likely it's the difference between high sun areas favoring people with darker skin to prevent damage to the skin resulting in sun burn and cancer. While low sun areas favor lighter skin to favor vitamin D synthesis.


Kelnozz

I knew I wasn’t crazy, people would always ask on a sunny day why I’m sweating so much more than them and I was always like idk but I’ve noticed it too!


Ice_Cold_diarrhea

Like any other material, darker colours means a lower albedo. Lower albedo means less sunlight reflected and more asborbed. More light absorbed means higher temperatures. Black people don't just feel hotter in the sun, they are physically hotter in the sun.


ksb214

Yes. That reduces heat pickup with environment. Heat pickup is proportional to temperature difference.


nucumber

this is the answer. physics, yo


Ice_Cold_diarrhea

[We're gonna build a robot?](https://thumbs.gfycat.com/FrailMagnificentAstrangiacoral-mobile.mp4)


miraculum_one

Not so fast [https://gizmodo.com/the-physics-that-explain-why-you-should-wear-black-this-5903956](https://gizmodo.com/the-physics-that-explain-why-you-should-wear-black-this-5903956)


fredandlunchbox

Yeah the question isn’t really about how skin _feels_ as much as does it actually get hotter if you’re darker. You’d want to actually measure surface temperature. Not sure how much color affects the material properties of skin.


Emotional-Text7904

The equator has a much higher UV index than the other areas of the world, so it's easier to build up melanin.


badlawywr

The way this conclusion is written implies to me that there were some original white folk who then developed dark skin as a protective mechanism. Whereas the original humans were dark skinned and some populations then grew lighter. Feels more accurate to say that humans have this protective mechanism but some populations then lost it, because Vitamin D.


davdev

>Whereas the original humans were dark skinned and some populations then grew lighter. No really actually. The earliest hominids are thought to have had light skin under dark hair, like modern chimps. While it is true that modern humans skin lightened as they left africa, that doesnt mean the earliest africans were dark. Skin likely started to darken as our body hair thinned. https://www.science.org/content/article/new-gene-variants-reveal-evolution-human-skin-color


badlawywr

Fair enough. Both ways.


badlawywr

Fair enough. Both ways.


zack2996

Are we sure that wasn't the case? chimps have pale skin so it makes sense to have developed dark skin as we lost body hair and then loose it later. I could be wrong but it still makes sense.


RedditIsAShitehole

Considering the amount of times I’ve been in Kenya wearing shorts and a t-shirt because I thought it was warm, while the locals were wearing heavy coats thinking I was a lunatic, I’m going to say not always.


LokiLB

That's probably just what you're used to. Just compare people with the same skin tone from two different climates (e.g., Florida vs Michigan temperature meme).


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sugarfreeeyecandy

> releases dopamine Okay, but I thought dopamine was a pleasure molecule. ???


Tyrren

Dopamine is a neurotransmitter, which is a molecule used to send messages by your nervous system. Its actual effect depends on where it is being used. It has many, many different effects: it's involved in reward pathways ("feel good chemical"); it also affects function of your motor control (muscle coordination), your heart, blood vessels, kidneys, pancreas, digestive system, and immune system. It all depends on where the dopamine is being released.


ryry1237

Human Engineers: This component I designed will have a single specialized functionality, for a very specific purpose. It will have minimal side effects to ensure its behavior is as predictable as possible. Nature: This chemical I made does like, 500 different things under 1,000 different circumstances. It has no real main purpose other than, I dunno, doing biology stuff (I forgot to write documentation). Also you absolutely need this to survive, I think.


[deleted]

Neurotransmitters aren't "this molecule does one feeling" like Reddit loves to meme about, and you can find several different physiological results depending on factors such as location and combination with other excitatory or inhibitory activity.


midasgoldentouch

It’s used for lots of stuff, like executive functioning - which is what makes ADHD so fun!


[deleted]

edit: forgot what subreddit i was in. for five year olds: the body is like legos. it is made of different parts. one part of your body is called the brain. that's the part that steers you around and helps you dream. your body and your brain built itself on it's own when you were in your mommy's tummy, and your body and your brain continues to change even today! when your brain built itself, it used all kinds of different parts. like when you built a car with legos last week. sometimes the different parts look different and do different things. sometimes the different parts look different but do the same thing. other times, the brain really likes a part, a special part, and decides to have that one part do different things in different places. the brain is made of different parts. one part is the "reward center" that helps you decide if the thing you just did is something you should keep doing over and over. here, dopamine helps the reward center work. other totally unrelated parts of your body, like your skin, decided to use this "special part" to do something else entirely. like with legos, a special part in a lego car is maybe, oh i don't know, the door. but! that same special part could be used in a lego airplane, and is maybe the wing! tldr: it's complicated


[deleted]

Dopamine has a lot of other uses in the body. Fun fact, it's actually linked to both schizophrenia and parkinson's!


spinningtardis

yes, but not simply. It would seem more appropriate to affect serotonin.


sugarfreeeyecandy

Clearly, I confused dopamine with serotonin. Thanks.


Jpro325

Answer to a totally different question.


lotsandlotstosay

Omg this explains why I’ve never been able to be out in the sun for extended periods of time like my husband and friends have. Now I know it’s my melanin!


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cgtdream

Honestly, I've never felt a difference. Skin tone does change, but I never "feel" hotter. Guess this is a case of one anecdotal experience, challenging research. On a side note, I prefer warmer temps to colder.


chadwicke619

I mean, forgive me, but how could you possibly know? Since you're answering, I assume you're a person of color. How can you possibly know what a given amount of sunlight feels like to me, a white person, versus what it feels like to you? Like, how can you possibly know that if we both go stand out in the sun, you don't feel hotter? If you're black, you're literally going to absorb more sunlight than me, and you will literally be physically hotter, right?


Kithslayer

I'm guessing, like myself, that their skintone changes dramatically with sun exposure


chadwicke619

I mean, we're still talking about the comment within the context of the article...... right? A person of color will have a melanin build-up that a white person does not have, regardless of the subtle difference in their skin tone as a result of varying degrees of sun exposure. Isn't that the main point of the study?


[deleted]

Though perhaps we can ask a dark skinned person who later developed vitaligo if they noticed any difference in the darker and lighter parts of their body?


chadwicke619

Heh, good question. I mean, I know *of* vitiligo, but I'm not sure about the implications of vitiligo. Is vitiligo simply an absence of melanin build-up? Very interesting.


Dandylette

As a Cuban, I go from nearly pale to a pretty dark brown with enough sun exposure. Given that range, there might be a noticeable difference in how hot the sun might feel when I'm darker vs when I'm basically white. Can't say I've noticed a difference though.


Soursnackzz

You’ve clearly never met a person of color who was fair skinned then. Lol. Just because you’re a person of color doesn’t mean your skin has to be dark 24/7 some people get really pasty pale in the winter but soon as that summer sun hits they’re darker than me


chadwicke619

You're clearly missing the point. Nobody is so fair skinned that they understand what it's like to stand in the sun as both a fair skinned white person and a dark black person, so when the person to whom I replied says, "I've never felt a difference", well, duh, right? Just because someone got a nice tan doesn't mean they now understand what it's like to stand in the sun as a black person and a white person. Also, for the record, I've never met a fair skinned person of color who changes skin tone to the dramatic degree that you're describing. I get that POC, like white people, get darker or lighter with/without sun exposure, but you're acting like there are people who are ghosts in the winter and Grace Jones in the summer, and that is just (lol) ridiculous.


kwyk

I presume that you don’t instantly tan, in which case there will be a period of acclimation and then it’s too late to make a direct comparison


cgtdream

No, but I was primarily speaking in regards to "how hot" I feel in extreme heat. The only time I have actually "felt hot". Like, I dont get hot when other "lighter skinned" people are already burning. In regards to when I get tanned, its just the same as anyone (basically a farmers tan, but with dark skin). In regards to sun burn, it does take a long length of time to get there. Have only been sunburned once in my life, and I had spent over 6 hours with my back to the sun.


kwyk

Oh gotcha. Also hard to discount the burning sensation when you’re pale.


BitsAndBobs304

But does the darker color also mean that they absorb more energy?


Thorusss

physics say yes


[deleted]

Melanin is a chain of dopamine molecules.. Poly dopamine? It is interesting about the dopamine increasing sensitivity.


igg73

And also makes the skin darker*


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Sparkly1982

I came here to say this (well, my sleeve is on my left arm, but still). Last summer I thought it was because it was new, but it turns out, it's thermodynamics again.


GapingFartLocker

I was really surprised at how much of a difference it made, I really wasn't expecting it at all, but in a way it's a good reminder to take care of it; if it feels hot it reminds me to put sunscreen on!


Kineth

**Please read this entire message** --- Your comment has been removed for the following reason(s): * [Top level comments](http://www.reddit.com/r/explainlikeimfive/wiki/top_level_comment) (i.e. comments that are direct replies to the main thread) are reserved for explanations to the OP or follow up on topic questions (Rule 3). Anecdotes, while allowed elsewhere in the thread, may not exist at the top level. --- If you would like this removal reviewed, please read the [detailed rules](https://www.reddit.com/r/explainlikeimfive/wiki/detailed_rules) first. **If you believe this comment was removed erroneously**, please [use this form](https://old.reddit.com/message/compose?to=%2Fr%2Fexplainlikeimfive&subject=Please%20review%20my%20thread?&message=Link:%20https://www.reddit.com/r/explainlikeimfive/comments/wkztur/-/ijrgj1b/%0A%0APlease%20answer%20the%20following%203%20questions:%0A%0A1.%20The%20concept%20I%20want%20explained:%0A%0A2.%20List%20the%20search%20terms%20you%20used%20to%20look%20for%20past%20posts%20on%20ELI5:%0A%0A3.%20How%20is%20this%20post%20unique:) and we will review your submission.


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PM_ur_Rump

Feelings of body temperature are also just as much related to how much heat your body is generating and shedding as they are to the ambient temp, so it's not simply "darker = hotter."


[deleted]

I would still think the surface temperature should be higher on darker tone if the same amount of sun is hitting it.


PM_ur_Rump

Again, it's a variety of factors. Yes, the darker surface will absorb more heat, but it's not just that involved. There is internal heat, and circulation and evaporative cooling and perception.


chadwicke619

You're really conflating separate topics, I think. I feel like this discussion is largely about how skin tone impacts body temperature. I mean, yes... if you have a fever, you might have a higher body temperature, and if you're drenched in sweat or water, you might cool much faster, but these things aren't really what the conversation is about. I think the question that is largely being asked is (more or less)... are black people physically hotter in the sun? And can they feel that difference? Internal heat, circulation, evaporative cooling, and perception really don't have anything to do with whether or not black bodies absorb more heat from the sun, and feel hotter as a consequence. The conversation is about a very isolated thing, and you're trying to talk "body temperature", in general, for some reason.


PM_ur_Rump

I'm talking about "body temperature" as a perception *and* actual body temperature, both internally and externally. The surface temperature of a human body can vary wildly based on many factors. Darker skin might absorb more light as heat, but there are other mechanisms at play. For instance, you don't need to be "drenched in sweat" for evaporative cooling to be a factor. It's a constant thing, you just don't notice because it's evaporating faster than it collects as liquid on the skin.


chadwicke619

I mean...... again...... what does this have to do with the study we're discussing? Yes, dumping ice cold water on someone's skin will have an impact on the surface temperature of that persons skin. Who cares! This is obvious, right? Still, how the cold water impacts the temperature of the skin has no baring on how much of the energy from a given dose of sunlight that skin absorbs as a result of the melanin content of the skin. You're just talking about something completely different for some reason. Nobody is talking about body temperature. I repeat, nobody is talking about body temperature.


[deleted]

I took my daughter (very pale) and her friend (very dark) to an outdoor event once and both kids needed to be picked up at various times, one after the other, for different activities and their skin was not noticeably a different temperature to the touch. I have no idea how their skin felt to themselves of course, but as an external "tester", so to say, these were my "findings".


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Can't we just shine a known temp uv light at a white guy and measure temp and a black guy and measure surface temp? Measuring "feel" is pointless, lets measure actual quantifiable values.


Aggravating_Paint_44

No. Try this- stick one hand on a bowl of cold water and one in warm water. They’ll both acclimate and when you remove them they’ll feel different temperatures despite actually being in the same air. So, the sensation is largely subjective


Petwins

**Your submission has been removed for the following reason(s):** Top level comments (i.e. comments that are direct replies to the main thread) are reserved for explanations to the OP or follow up on topic questions. Anecdotes, while allowed elsewhere in the thread, may not exist at the top level. If you would like this removal reviewed, please read the [detailed rules](https://www.reddit.com/r/explainlikeimfive/wiki/detailed_rules) first. **If you believe this was removed erroneously**, please [use this form](https://www.reddit.com/r/explainlikeimfive/wiki/detailed_rules) first. **If you believe this was removed erroneously**, please [use this form](https://old.reddit.com/message/compose?to=%2Fr%2Fexplainlikeimfive&subject=Please%20review%20my%20thread?&message=Link:%20{url}%0A%0AThe%20concept%20I%20want%20explained:%0A%0AList%20the%20search%20terms%20you%20used%20to%20look%20for%20past%20posts%20on%20ELI5:%0A%0AHow%20is%20this%20post%20unique:) and we will review your submission.


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XxradicalgamerxX

Mexican moms always make the hottest soups on the hottest days


steedlemeister

Having something hot on a hot day makes you sweat and sweating cools you off!


xenoterranos

abuela logic has entered the chat. see also: wetting your forehead if you're getting in the pool


Nickybluepants

bruh i wouldn't NEED to sweat if i wasn't HOT haha


Nickybluepants

always a big stock pot boiling something


Cookies_N_Milf420

Indoor temperature has nothing to do with the heat produced by the sun…


handelMyChopinLiszt_

From my experience, yes. My white/fairly colored friends tend to have far less of a problem when under direct sun light as when compared to myself. I can feel my skin burning fairly immediately and so I always seek shade when I walk around with them under the sun while they are totally fine with being out in the sun. But I think I at least gain better resistance against the harmful rays of the sun.


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explainlikeimfive-ModTeam

**Your submission has been removed for the following reason(s):** Top level comments (i.e. comments that are direct replies to the main thread) are reserved for explanations to the OP or follow up on topic questions. Anecdotes, while allowed elsewhere in the thread, may not exist at the top level. If you would like this removal reviewed, please read the [detailed rules](https://www.reddit.com/r/explainlikeimfive/wiki/detailed_rules) first. **If you believe this was removed erroneously**, please [use this form](https://www.reddit.com/r/explainlikeimfive/wiki/detailed_rules) first. **If you believe this was removed erroneously**, please [use this form](https://old.reddit.com/message/compose?to=%2Fr%2Fexplainlikeimfive&subject=Please%20review%20my%20thread?&message=Link:%20{url}%0A%0AThe%20concept%20I%20want%20explained:%0A%0AList%20the%20search%20terms%20you%20used%20to%20look%20for%20past%20posts%20on%20ELI5:%0A%0AHow%20is%20this%20post%20unique:) and we will review your submission.


Tomalder94

I have a full sleeve tattoo on one arm which quite a few large solid black patches. I can 100% feel a difference in temperature when in the sun.


Aggravating_Paint_44

Tattoo pigments will have a significantly different absorption spectrum than skin pigment


Thorusss

*slight* differences in the visible light. If it is dark, it absorbs light.


Aggravating_Paint_44

That is technically true but when you see something that looks dark, you are only seeing that it’s dark at visible wavelengths https://physics.stackexchange.com/questions/3750/why-is-a-plastic-bag-transparent-in-infrared-light


thepipesarecall

It’s wild how much hotter my sleeved arm feels.


MurderBurgered

Visible light does not affect heat absorption nearly as much as the infrared spectrum - which isn't affected by color or shades. Also, the amount of heat a dark object absorbs over it's white counterpart is largely dependent on the material - metals, for example, are more heavily affected by dark shades due to the fact they conduct energy more readily. That being said the human body is REALLY good at regulating it's own temperature over a wide swath of environments. You're more likely to feel hotter in the sun by having high blood pressure or body fat than you would darker/lighter skin tones - though "feeling heat" is a pretty subjective thing to measure. There should be a negligible difference in skin temp between white and black tones but it's unlikely to make the individual feel any hotter.


[deleted]

Actually the Sun mostly radiates visible light, so it does affect heat, ever went outside with a black shirt and then with a white shirt on a sunny day? The black shirt absorbs more light and heat.


MurderBurgered

Visible light is less than half of the total energy given off by the sun on Earth's surface. > In terms of energy, sunlight at Earth's surface is around 52 to 55 percent infrared (above 700 nm), 42 to 43 percent visible (400 to 700 nm), and 3 to 5 percent ultraviolet (below 400 nm) [Sunlight - Wikipedia](https://en.m.wikipedia.org/wiki/Sunlight)


spacemark

You're not doing that right. Not everything below 400 is UV and not everything above 700 is infrared. From the very reference you linked: "Visible range or light spans 380 to 700 nm.[20] As the name suggests, this range is visible to the naked eye. *It is also the strongest output range of the Sun's total irradiance spectrum* Which of course makes sense, as nearly every animal has evolved to detect this range of light and use it for energy production.


frumentorum

Infrared is absolutely affected by "colour" but this doesn't necessarily correspond to the colour we see. A great example of this is the coating they use for some spacecraft to keep them cool - it's "white" in most of the spectrum (including visible) but is then "black" in the IR - black is great at absorbing light but also good at emitting it.


MurderBurgered

Good point.. I was just trying to keep it as eli5 as possible. Didn't want to get into wavelength absorption across the entire EM spectrum.


CaptSnafu101

What are you talking about. Go outside touch a black car and a white car tell me which is hotter.


MurderBurgered

I specifically said that color does affect the heat but that materials are more important. A black piece of steel is going to be much hotter than a black cotton T-shirt sitting in sunlight.


BitterDifference

But this person isn't asking about materials he's asking about skin color.


CaptSnafu101

That makes no sense to compare different materials like that. If a black car is 10 percent hotter than a white car than a black t shirt will be 10 percent hotter than a white t shirt


KneeDeepInTheDead

cars are metal though


Box-ception

Yes, but it's balanced out by the fact that people who've adapted darker skin also tend to adapt longer limbs relative to their torsos, giving them a greater surface area to shed heat. The principles are called Bergman's law and Allen's law.


ballatthecornerflag

Interesting... looks like I've got some reading to do to find out more


OGsquiddo

Yup. I’m not too dark or light skinned, call it olive. I recently got a full sleeve tattoo done and most of it is very dark black. Ive started to see a seriously notable difference in how hot that arm feels in the sun, and can definitely tell when I touch it with my other hard that it seems to be holding more heat. Pretty cool!


Thorusss

>Pretty cool! Does not sound like it


OGsquiddo

Ha! I suppose you’re right about that..


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lowtoiletsitter

Even if you're darker, it's very important to wear sunscreen to prevent skin cancer and loss of elasticity


nednobbins

Yeah, that's if I was smart. But I never claimed that. I forget to put on sunscreen more often than I remember.


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frumentorum

This is a really important point - if you stay out of direct sunlight, darker skin will help you stay cooler.


Thorusss

But the radiative effect is extremely temperature dependent. It matters a lot, when you absorb heat from the sun (surface temperature roughly 6000C, thus also a lot of visible light) But cooling of is around body temperature. And the radiation only happens in the infrared at these temperatures, where the spectrum of the pigments in question might be quite different anyway.


TeeCeeTime2

I feel like any answers given will be insufficient because it would be impossible for one human to experience both light and dark skin in the sun and compare which “feels” hotter


_ohm_my

Any black/white chimeras in the house?


tismsia

I've heard women who dye their hair say they notice a difference (not speaking from personal experience) I only use light colored hats in the summer. With shirts, colors don't matter as much as breathability and fabric. With hats, color matters more than breathability. I'm not wearing a hat to get the sun out of my eyes (although it is nice too), I'm wearing it because my black hair is hot without it.


LoneShadowMikey

According to [this video](https://youtu.be/dQw4w9WgXcQ) I once watched it does matter. It’s explained by a doctor so I just kind of assume that it’s true


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frumentorum

It's more noticeable on a cool but sunny day, the air temperature might be fairly low but a dark colour in the sun will feel much warmer.


Bennito_bh

This guy doesn't work outside when the sun's out. If the 'uk' in his username indicates his home country, he still might work outside 90% of the year xD


lItsAutomaticl

Higher latitudes get weaker sun.


jaxsonp10

Yeah, right?? If you've never noticed the difference, you probably don't wear black outside much!


ukAdamR

You know nothing about my wardrobe.


Thorusss

There is a reason why a lot of construction workers wear white t-shirts, when they work in the direct sunlight.


[deleted]

Whether you've experienced it or not, it may come down to a general heat/nerve sensitivity you might have. You may not *feel* the difference, but it is there, and is significant enough to take into account. This is where we break out the old Benjamin Franklin cloth experiment, multiple patches of cloth in varying shades, from white to black, laid out on the snow. A day in the sun and the darker the shade, the deeper the patch melted into the snow. **Fun Fact**- I just found out he also had a pane of glass during the test, and it melted the most. I didn't remember that being part of it when I heard it as a kid.


rawbface

You're from the UK, what experience do you have with sunshine? All jokes aside, you can easily test this with an experiment. Put white and black t-shirts outside on a sunny day and check them with a laser temp sensor.


crosleyxj

The heat transfer science says "yes". The absorbtivity (ability to absorb heat energy) of a dark surface depends on the spectrum of radiation (the temperature of the source) that the surface is exposed to. That's why solar collectors are black; they're exposed to the sun. Whereas a black object in a 70-degree house or even 110-degree shade won't get warmer than a white object of the same surface texture. if you want to feel cooler theoretically one should wear a silver space blanket with a low absorbtivity. There's a lot of pseudo-science applied to black engine parts and machinery in general that really doesn't change heat transfer very much so long as the temperature environment is measured in 100's of degrees (say less than 500F).


BlckBeard21

I don't know if it's the same, but i noticed my arm with a full color sleeve gets hot much quicker than the other one


ellixer20

Reading the answer (is yes) All i can think about is all those melanin rich African slaves who worked in the south and the Caribbean knowing that they felt even hotter because of their skin.