Wearing black in a desert


by kjamha
Tags: black, desert, wearing
Karl Coryat
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#19
Feb12-12, 02:36 PM
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Sounds like no one here has been to the Mideast. When I lived in the UAE, which is incredibly hot in the summer, the traditionally clothed men wore white. The women wore black and were veiled, on the occasions when they left the house and went into public. Considering that men call the shots in that culture, I'd conclude that in a very hot sunny climate, white is better than black.
cepheid
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Feb12-12, 09:06 PM
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Quote Quote by Karl Coryat View Post
Sounds like no one here has been to the Mideast.
Way to NOT read the thread carefully.

Quote Quote by Karl Coryat View Post
When I lived in the UAE, which is incredibly hot in the summer, the traditionally clothed men wore white. The women wore black and were veiled, on the occasions when they left the house and went into public. Considering that men call the shots in that culture, I'd conclude that in a very hot sunny climate, white is better than black.
Yes, it is a patriarchal society, and yes, women in many ways are oppressed there. But I do not think that that oppression extends to deliberately trying to make women suffer discomfort for no good reason (which would be sadism). There's just nothing to justify that assertion. The motivation for the burka has to do with the extreme notion that exists in that society of what modesty is. Assuming that the difference in colouration is motivated by practical knowledge of heating and cooling, rather than just being simply cultural (which is a much more likely explanation) is just silly. I think that the Burka is just traditionally dark coloured, and the stereotypical "Arab dude" costume is just traditionally white. There is no explanation other than simply, "that's the way it has always been."

Besides, we haven't yet established conclusively whether the black, loose flowing burka isn't *better* than the white, loose flowing Arab dude outfit. So using your own tenuous assumptions about another culture to come to some sort of conclusion about physics seems even more unsound.
sankalpmittal
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#21
Feb13-12, 12:30 AM
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You must have across like - Bedouins or Arabs wearing loose black ropes and loose black clothes in deserts.

This is because this clothing acts like poor man's air conditioner. How ?

Here is the answer :
Firstly cloths (black or white) are itself poor conductor of heat. But this reason is negligible though.

Main reason : The cloths being loose traps air inside them. As we know that air is poor conductor of heat , it prevents the heat to be gained by the body. In other words , it insulates the body. Now the loose cloths are black because black is a good absorber and radiator of heat. When black cloth absorbs heat , it sets up convectional current in the air being trapped inside. Air then becomes lighter but why do you think that there will be one directional movement ? It will expand in all directions. It displaces heavier and cooler air to move in interior thus giving cooling effect to desert traveler. At night also , it does not allow the body heat to be lost. Similarly , what if there were white clothing ?

It reflects heat and does not develop convectional current and hence will not be of greater cooling effect. During night , the black cloth which has absorbed heat dissipates it in body via air trap. It protects the body from cold breeze.
Moreover it causes windy air to enter during day , which causes evaporation of sweat faster !
NascentOxygen
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#22
Feb13-12, 12:36 AM
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Quote Quote by sankalpmittal View Post
YMain reason : The cloths being loose traps air inside them. As we know that air is poor conductor of heat , it prevents the heat to be gained by the body. In other words , it insulates the body. Now the loose cloths are black because black is a good absorber and radiator of heat. When black cloth absorbs heat , it sets up convectional current in the air being trapped inside. Air then becomes lighter but why do you think that there will be one directional movement ? It will expand in all directions. It displaces heavier and cooler air to move in interior thus giving cooling effect to desert traveler.
So why do most middle eastern men wear white?

I was sort of in agreement with you, up until this about black cloth:
During night , the black cloth which has absorbed heat dissipates it in body via air trap. It protects the body from cold breeze.
Being black, it will absorb the night chill more quickly than does white.
sankalpmittal
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#23
Feb13-12, 12:46 AM
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Quote Quote by NascentOxygen View Post
I was sort of in agreement with you, up until this about black cloth:

Being black, it will absorb the night chill more quickly than does white.
Careful with the terms !
No object absorbs night chill or coldness ! Its about gain or loss of heat which causes sensation of hotness or coldness. When wind strikes the cloth it will be conducted by black and white cloth equally. Nothing is being radiated. From day (when there is radiation) , black has absorbed more heat and will dissipate more heat in air trapped as well at night.

So why do most middle eastern men wear white?
Is it desert in middle east ? In India and at normal places except deserts , people wear loose and light coloured clothes in summer and dark and tight clothes in winter. That's it.
klimatos
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#24
Feb14-12, 03:36 AM
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Before the days of store-bought clothing, Bedouin men and women wore black because the mohair that they used to weave cloth came from black goats--and still does. I refer you to a verse from the Song of Solomon, "Thy hair is like a flock of goats on the mountainside".

Today, most Bedouin wear cotton store-bought clothing, and white has become the standard. Black is still the traditional, conservative color and is the color of respectable married women even today.

White reflects more visible light, but its infrared albedp is usually no different than black colored fabrics. When it comes to reflecting or absorbing body heat, there will be little difference. The loose robes of the Bedouin do circulate air as they move.

Mohair or wool is still preferred for desert excursions in very hot weather because of its insulating ability. I remember a Bedouin guide remarking that, "If I had known it was going to be this hot, I would have worn my thicker robe!"
NascentOxygen
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#25
Feb14-12, 11:14 PM
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Quote Quote by sankalpmittal View Post
Nothing is being radiated.
The heat in the cloth is being radiated into space. Black radiates heat better, so black becomes chilly more quickly. Alpine climbers and arctic explorers seem to prefer white clothing, not dark, even though I think dark would be safer by being more visible if they become partly buried.
In India and at normal places except deserts , people wear loose and light coloured clothes in summer and dark and tight clothes in winter.
On winter nights, does the interior of a black car chill noticeably faster, when it is parked on the street, compared with a white car?
NascentOxygen
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#26
Feb14-12, 11:18 PM
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Quote Quote by klimatos View Post
Before the days of store-bought clothing, Bedouin men and women wore black because the mohair that they used to weave cloth came from black goats--and still does.
Fair enough, then. But why do desert goats have black hair, when a light colour would seem to be better suited to hot climates?


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