Clothing to beat the heat?

[ScienceNostalgia101]

I keep hearing conflicting stories about what clothing is most effective at beating the heat. Some say white clothing is best to reflect the heat away. Others say dark clothing is best to absorb heat from the body and then radiate it elsewhere. (I would assume white during the day, dark at night?) Some say loose clothing is best to allow convection currents under the clothes, others say tighter clothing is best to radiate heat. Some say it's more effective to wear less, others to wear more. (It's possible the former's just an excuse by narcissists to show as much skin as possible, but it's possible the latter's an excuse by puritans to put modesty over health.)

 

Do all these things depend on time of day, solar angle, temperature, wind, and humidity? Or are the answers more simple than the debates over this are made out to be?

[joigus]

I'd say human skin and sweat are the major factor in evacuating heat. Evaporation of water is the most efficient way for us humans to get rid of heat. It's no coincidence that we've evolved that. It's been proven that human skin is our trump card with respect to furry animals, allowing humans to use persistence hunting in very intense heat until prey die of heat exhaustion. Interesting studies by Harvard anthropologist Daniel Lieberman.*

Colour is not nearly as efficient, although I would recommend white for reflectivity.

*About persistence hunting and adaptation to running. There are other studies more directly related to skin.

Edit: Also pick up anything by Nina Jablonski on human skin. There's a lot on the web. 

Edited August 12, 2020 by joigus

[MigL]

3 hours ago, ScienceNostalgia101 said:

(I would assume white during the day, dark at night?)

Good way to get hit by a car...

[Phi for All]

I like some of the new fibers that wick moisture away from the body and dry in seconds. Covers the skin, but lets it breathe. They've come a long way since polyester leisure suits.

19 minutes ago, MigL said:

Good way to get hit by a car...

These are people who think their clothing affects sunlight at night. We can lose a few.

[Externet]

From a years old thread, seems these Tuareg people know how to deal with it better than anyone... I still do not get how they do it.  Body temperature is less than ambient Since milennia before hi-tech fabrics...

And not always in white :

-Images borrowed from the web-  If against rules, please delete.

Edited August 13, 2020 by Externet
Added image

[Endy0816]

12 hours ago, Externet said:

From a years old thread, seems these Tuareg people know how to deal with it better than anyone... I still do not get how they do it.  Body temperature is less than ambient Since milennia before hi-tech fabrics...

And not always in white :

-Images borrowed from the web-  If against rules, please delete.

 

Found an interesting article on this:

Quote

The results were clear. As the report puts it: "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."

Bedouins' 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/science/2012/aug/19/most-improbable-scientific-research-abrahams

 

Granted be curious to find out how much an impact higher levels of humidity would have.

[ScienceNostalgia101]

Yeah, convection sounds like it could only do so much good if there is an actual difference in dewpoint to allow sweating to help.

 

Just so we're clear I'm referring to dark clothing in a hypothetical circumstance where all other considerations are already addressed. (Eg. Taking public transit everywhere you go, or not going out at night except through walking trails to which motor vehicles have no physical access at all, let alone lawful physical access, etc...)

[dimreepr]

It's hardly surprising that people have found a way to insulate themselves from the extremes of temperature; since they continue to live there...