329
you are viewing a single comment's thread
view the rest of the comments
[-] frisbird@lemmy.ml 2 points 3 days ago

That's not measuring body temp, it's measuring the heat radiating off the shirts. The fact white isn't radiating heat off the shirt means that if you are inside the shirt producing heat then it's not letting your heat out

[-] Buddahriffic@lemmy.world 4 points 3 days ago

Or the manequin holding up that shirt in the sunlight doesn't have as much heat to give off as the others do because the lighter shirt reflected more heat away prior to that.

I'm not aware of any heat-trapping properties of the colour white, other than it'll reflect visible light. Though I think how it handles IR and UV light might be more relevant than visible. Like would a black shirt that reflects UV light well feel cooler than a white shirt that doesn't?

[-] frisbird@lemmy.ml 1 points 3 days 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 3 points 3 days 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 1 points 3 days ago* (last edited 3 days 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?

[-] frisbird@lemmy.ml 1 points 3 days 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 1 points 3 days 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.

[-] JimmyMcGill@lemmy.world 3 points 3 days ago* (last edited 3 days ago)

No

It means white is not absorbing the heat so it doesn’t radiate as much. White reflects the heat while black absorbs it. The more you absorb the more you radiate.

If what you said was true the heatmap would be even across the shirt. It isn’t

this post was submitted on 09 Sep 2026
329 points (99.1% liked)

People Twitter

10404 readers
161 users here now

People tweeting stuff. We allow tweets from anyone.

RULES:

  1. Mark NSFW content.
  2. No doxxing people.
  3. Must be a pic of the tweet or similar. No direct links to the tweet.
  4. No international politcs
  5. Be excellent to each other.
  6. Provide an archived link to the tweet (or similar) being shown if it's a major celebrity, figure or any politician. You can replace the addres of .x.com to xcancel.com in the address. https://web.archive.org/save is an option. Archive.is is no longer recommended because they remove/alter content.
  7. If a tweet (or similar) makes a statement of fact, either mark it as "satire" in the body or provide the original source link backing up the statement (see rule 6)

founded 3 years ago
MODERATORS