Why do the tuaregs wear dark blue?

[temujin]

Why do the tuaregs wear dark blue..?

Hi,

I tried to find a suitable forum for this question...this seemed to be the most appropriate.

The Tuaregs living in the Sahel/Sahara region in North Africa cover their body completely in dark dark blue clothing. A long time ago I read somewhere that covering their entire body in this color is the best way to keep the water balance and the heat away.
Does anyone know the physical explanation behind this.? Does not dark clothes absorb more energy than white clothes (so wearing dark clothes should be much warmer)...?


regards
t.

 

[enigma]

I don't know where this question belongs either, but you'll probably get better response in General Physics.

 

[hexhunter]

hmm? water is actually blue, but it's only noticable at large quantities, and the body is somethinbg like 70% water, so perhaps that has something to do with it

 

[Curious6]

It makes them look all pretty so they feel satisfied.

 

[rdt2]

Yes, I think the explanation is more likely to be cultural rather than thermodynamic. Many 'tribes' (in the widest sense) use clothing as an identifying uniform (blue jeans?). If the blue had any intrinsic value then everyone in such climates would have adopted it.

 

[Berislav]

I think that the reason is when the air around their bodies becomes warmer than the outside air it starts to circulate (pressure difference) and then they feel more comfortable.

 

[Sarahchichi]

temujin,
Tuaregs wear dark blue clothes aim at reducing the effect of UV radiation from the Sun. Also, they always have a cloth around their mouth and nose to keep a moist flow of air as they breathe. I think it is this piece of cloth that keeps the water balance and heat away.

 

[dextercioby]

BTW,the water,pure chemical dihydrogen monoxyde,is incolor.

Daniel.

 

[temujin]

hi again

finally, I found the answer somewhere on the web.
I´ll post it here in case somebody might be interested.

Black clothes absorb more sunlight and heat radiated from the body than white clothes. However,if they are loose-fitting, and there is wind, the wind convects the heat away faster than it is absorbed. White clothing reflects sunlight, but also reflects internal heat back towards your body, so the net effect under identical conditions is less cooling than with black clothes...



t.

 

[hexhunter]

so in hot conditions you should have a dark inner layer and a light outer layer?

 

[temujin]

That´s what I was thinking as well.

Some stuff related to this is here:

http://www.politikforum.de/forum/archive/29/2005/03/3/97240

t.

 

[Ryan Lucas]

hmm? water is actually blue, but it's only noticable at large quantities, and the body is somethinbg like 70% water, so perhaps that has something to do with it

WHAT? Water is NOT blue, this is the most elementary basic knowledge! water is clear, it reflects the blue of the sky, which is blue because of the gas molecules dispursing the blue region of the EM spectrum!

 

[Doc Al]

the color of water

WHAT? Water is NOT blue, this is the most elementary basic knowledge!

Actually, water is blue. http://www.dartmouth.edu/~etrnsfer/water.htm

 

[Danger]

Actually, water is blue.

That's a very interesting link. Thanks, Doc.

 

[danAlwyn]

Black clothes absorb more sunlight and heat radiated from the body than white clothes. However,if they are loose-fitting, and there is wind, the wind convects the heat away faster than it is absorbed. White clothing reflects sunlight, but also reflects internal heat back towards your body, so the net effect under identical conditions is less cooling than with black clothes...

I have a cousin who did some field work for archaeology in the Middle East, and he claimed that this was the reason that they wore black robes. He also did say that once the air inside your clothes got warm enough it started expanding outward, and that the net effect was sort of like a constant wind blowing through your clothes, cooling you off.

 

[Ryan Lucas]

So is this to say that an ocean on a planet without an atmosphere would still be blue? Very interesting, thanks Doc!

 

[Ryan Lucas]

Thanks for correcting me Doc, very interesting read! Thanks

 

[temujin]

and another good reason for wearing black in hot climate is that nobody can see these big sweat spots on your back and under your arms
:-)

t.

 

[Danger]

It might be irrelevant at this point, but as to the question of why dark blue, it might just be that this particular culture (about which I know nothing) doesn't have ready access to truly black dyes.

 

[thearny]

I always understood that the cultures in warmer climates were dark colours because they move in the shade, and as dark colours also emit heat better it is cooler. Obviously when standing in direct sunlight the lighter colours are better to reflect the heat.