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In Jurassic Park, Dr. Ian Malcolm says he wears black to stay cool even in warm or hot climates. Is there truth to his claim, is it cinematic fiction, or character development?

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It is true under certain circumstances anyway (e.g. air is not still). This is really a question for Physics.SE, not SciFi, but here's a link with more info.

In brief, in sunlight, black absorbs more of the light, so it doesn't get through to you; if the material is fluffy, then the outside layer absorbs all the heat and is cooled by the wind; inner layers are dark and cool. Also, the hot air rising on the outside can create air currents that are strong enough to help cool you underneath the clothes if they're loose enough. (Air currents are extremely important for keeping cool, since humans sweat, and evaporation is a major source of cooling.)

Incidentally, it does not appear to me that Dr. Ian Malcolm as shown in the movies is wearing clothing that optimizes his ability to stay thermodynamically cool. Rather, the clothing appears to be chosen for him to stay socially cool.

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    Socially cool, indeed. I believe he also said he always wears black so he never has to decide what to wear. – Jeffrywith1e May 1 '11 at 17:02
  • I would have thought it's a Skeptics.SE question, not a Physics.SE question. – Andrew Grimm May 1 '11 at 23:34
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    @Andrew Grimm - Skeptics.SE has taken a stance that they have no expertise in any particular field, but are good at finding references. If you want the physics discussed and explained, Physics.SE is the place to go. If you want to find something online that describes the answer, Skeptics.SE is the better choice. – Rex Kerr May 2 '11 at 2:53
  • "black absorbs more of the light, so it doesn't get through to you" - Huh? If the material absorbs more light than a white material would, that means it heats up faster, so it'll be warmer against your skin. Similarly, in astronomy on object's "albedo" tells you how much light it reflects, with lighter bodies having higher albedo than darker ones, and all else being equal, higher albedo means lower temperatures (also, this page says "lighter clothing keeps you cooler") – Hypnosifl Jul 14 '16 at 22:58
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    OK, I did some googling and it seems there has been empirical research into this stuff--the study cited here shows that if there's wind faster than about 3 m/s, black clothing is better, otherwise white is better. However it's not for the reason you gave involving opaqueness--rather, it's because black clothing is more efficient at creating a layer of heated air immediately around it, and then a modest wind can continually blow that heated air away, transporting heat away from the body. Would you consider incorporating this into your answer? – Hypnosifl Jul 27 '16 at 20:08
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This is fiction. Wearing black actually heats you up, wearing white will cool you down.

It has to do with colors and light. Light works on an RGB model, or additive model, which means you start at white and add to get to black. How pigments work are the same, if all the pigments are off, you've got white, if they're all on, you've got black.

Pigments that are on take in the colors you're not seeing, in the case of blue, red light and green light are being absorbed and blue light is being reflected. When you have white objects, because all of the pigments are off, red, green and blue light is being reflected. The opposite is true with black, red, green and blue light is absorbed by the object, making it hotter.

sources:
High School Physics class
http://phoenix.about.com/od/car/qt/carcolor.htm
http://www.colormatters.com/colorheat.html

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    You really confused it all up. Lights work in an additive model. You add lights up to white. The absence of light is black. Pigments work in a subtractive model. You add pigments up to black, white is the absence of pigment. Other than that, you're correct. But you didn't need to get into that territory. Just say "white reflects all light, black absorbs all light". – R. Martinho Fernandes May 1 '11 at 3:54
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    This is simplistic, and doesn't explain why Bedouins usually wear black. – user56 May 1 '11 at 10:43
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    Darker colored materials will heat up more when exposed to light. In daytime he would be cooler all other things being the same with lighter colored garments. Thats also true of Bedouins, it seems there clothes are not optimal. White reflects light without converting it to heat, so it is cooler. They probably wear black ,because white plus dirt looks bad. – Omega Centauri May 2 '11 at 20:13
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    @OmegaCentauri Tests shows that it actually doesn't matter what color is the Beduin robe - in case of black one, the heat is lost before it reaches skin – Yasskier Jul 14 '16 at 22:58
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Black bodies radiate away heat when in shade. Dr. Malcolm intended to be in shade.

  • Evidence needed? – bleh Jul 14 '16 at 22:10

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