• freagle@lemmy.ml
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    5 hours ago

    I’m not aware of any heat-trapping properties of the colour white, other than it’ll reflect visible light.

    It reflects emr in the visible spectrum. It probably reflects emr slightly beyond the visible spectrum too, like infrared. Then you make a tube out of it and put a hot body in the tube. It will reflect the war back at the body.

    • Buddahriffic@lemmy.world
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      4 hours ago

      Ok yeah, you’re right that that is a factor. Though when in direct sunlight, the amount of heat reflected will be much more significant than the amount trapped. But it could be more significant in low light situations.

    • balsoft@lemmy.ml
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      4 hours ago

      That doesn’t make any sense, sure it will reflect slightly more heat from your body back inside but that is negligible because the vast majority of body cooling happens due to convection and/or evaporative cooling and/or “contact cooling” depending on heat/humidity/how loose your clothes are. Radiation plays very little effect in that cooling.

      Basically consider this: your body is emitting black-body radiation at 310K, and the sun is emitting black-body radiation at 6000K (+ a bunch of other radiation coming from all the fusion happening inside). Which one is a more important factor when you’re deciding the reflectivity of the shield between yourself and the rest of the universe?

      • freagle@lemmy.ml
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        3 hours ago

        It depends on whether you’re standing in direct sunlight for extended periods of time or not. Generally, staying in direct sunlight for extended periods of time is going to do so much to you that the albedo of your shirt isn’t going to really do too much.

        • balsoft@lemmy.ml
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          3 hours ago

          I have a black long-sleeve and a white long-sleeve which both promise SPF-50 (I don’t really trust them fully but they do seem to work well enough). The black one definitely feels hotter in the sun.

          Basically it’s either ambivalent (if you’re not in direct sunlight or the clothes are thick and loose so they don’t transfer most of the absorbed heat to you) or white wins.