Black robes are COOL
![[Corel] Tuareg in black burnoose leads his camel, Sahara, Mali](2001-12-12-black-robes.jpg) Q: In sun-drenched climes is there an advantage to wearing long black coverings, instead of
white (as I've seen so often in the movies). --Stay Cool,
Maynardville, Tennessee
A: Yes. Black robes create a pleasant breeze wafting up a robe from the desert floor and out the loose
robe top.
[Corel] Tuareg in black burnoose leads his camel, Sahara, Mali
Scientists checked into the matter by having a man stand in the hot desert sun first in a white robe and
then in a black one. They found that the black robe absorbed 2.5 times more solar radiation and was
11 degrees Fahrenheit (6 degrees Centigrade) hotter than the white one. About what I, having walked
on black asphalt roads and white concrete ones in my bare feet, expected. Here's the kicker: The skin
temperature was the same in either robe; the man felt cooler in the black one.
The extra warm air trapped by the black color experiences a buoyancy force equal to the weight of the
cool air it displaces. Cooler air from below pushes the warm air up and out of the robe top. This, in turn, creates a breeze. The breeze
evaporates sweat, cooling the robe wearer, and moves the sweat-laden air out the robe top. The loose-fitting burnoose is a solar air-conditioning system.
(Answered by April Holladay, science correspondent, December 12, 2001)
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