Why Does Ordinary Water Appear Blue in a White Bucket?

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Discussion Overview

The discussion revolves around the phenomenon of why ordinary water appears blue when contained in a white bucket, particularly in a controlled environment without external light sources. Participants explore various explanations related to the optical properties of water and its interaction with light.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant notes that water is generally considered a clear liquid, but questions why it appears blue in a white bucket, suggesting a need for clarification on this observation.
  • Another participant proposes that water absorbs other colors, indicating that clear does not necessarily mean colorless, and mentions that underwater photography tends to show bluer hues at greater depths.
  • A different viewpoint suggests that the blue appearance of water is due to its enhancement of blue wavelength scattering, with deeper water appearing more blue due to increased scattering effects.
  • One participant references personal experience with a specific location, asserting that the water appears blue regardless of sky conditions, implying that factors other than the sky may contribute to the color.
  • A later reply expresses satisfaction with the information provided, indicating a level of understanding achieved through the discussion.

Areas of Agreement / Disagreement

Participants present multiple competing views regarding the reasons for water's blue appearance, and the discussion remains unresolved with no consensus reached on a singular explanation.

Contextual Notes

Some claims depend on specific conditions, such as water depth and the presence of impurities or minerals, which may influence the perceived color of water.

Typhoon_rising
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blue Water !

i have been told that water is a clear liquid ignooring any impurities, and that the ocean is blue because of the sky. This i am perfectly willing to accept, however if you fill a white bucket full of ordinary water from a tap in a white room with no windows, why does it appear blue?

Thanks, Chris
 
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Typhoon_rising said:
i have been told that water is a clear liquid ignooring any impurities, and that the ocean is blue because of the sky. This i am perfectly willing to accept, however if you fill a white bucket full of ordinary water from a tap in a white room with no windows, why does it appear blue?

Water absobs the other colors somewhat. Clear doesn't necessarily mean colorless. That's also why pictures taken underwater tend to get bluer as you go deeper. In some places, the tap water may also contain trace minerals that make it more blue.
 
The reason water is blue isn't because the sky is blue. It's because the water enhances the scattering of the blue wavelengths. The more water i.e., deeper) the more scattering of blue. That's why shallow water appears clear, deeper water appears green, and deeper water appears blue. Eventually, the visible wavelengths no longer penetrate, and the deepest water is absent of visible light.
 
I have visited http://www.nps.gov/crla/" many times, it is blue whether the sky is cloudy or clear.
 
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Thanks a lot, i understand now :D
 

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