# A couple Oceanography questions

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My Oceanography teacher from time to time gives us information to look-up that he doesn't know for extra credit. So, I turn to you all to assist me in formulating some answers.

1) Why don't Violet wavelengths penetrate deeper than blue or green? If they did, then you could say that the shorter the wavelength, the longer the penetration of light.

2) Why do clouds have different shapes? I'd guess because it's all relative to how the water vapors condense at the Dew Point and take shape, but I'm not positive.

3) Finally, what's the difference between a calorie and Calorie? calorie is the amount of heat required to raise/lower the temperature of water. Calorie on the otherhand, I'm not sure of how to explain it. Something to do with food

Those are the questions. Anyone?

2. ### David-S Second Unit

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3)If you look at some good conversion tables (for energy) you should be able to figure it out (no, i won't give you the answer :p) but i will say it has to do with orders of magnitude)

3. ### Leila Dougan Screenwriter

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1) The color of the water is dependent on two things: the particles in the water and the wavelength of the light hitting it.

Refer to the Rayleigh scattering theory (named after Lord Rayleigh). It predicts that independant particles smaller than a wavelength of light will scatter light with a scattering cross section proportional to the inverse of wavelength to the 4th power.

Thus shorter wavelengths are scattered more strongly than longer wavelengths. For the same reason, longer wavelengths will penetrate the scattering region more deeply (the attenuation coefficient is also proportional to the inverse of wavelength to the 4th power).

The deep sea looks blue-green because seawater has a transmission maximum in the blue-green thus dispersion properties are dominating here, and the other wavelengths are being absorbed.

4. ### Kevin P Screenwriter

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Clouds have different shapes due to air currents (wind), differences in air temperature at different altitudes and locations, etc.

If I recall correctly, a Calorie = 1000 (or 100 or something) calories. Case sensitive naming, sounds like Unix.

KJP

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