What color is water?

Filming on a gray overcast day. I debunk the common misconception that water's blue color comes from the reflected sky. The distant ocean here looks DARK BLUE with gray reflections, yet the sky is gray. The visible reflections are gray, yet this doesn't stop the water looking blue. Also we see many shades of blue-green and blue in the spots where white bubbles are mixed in. With a gray sky!

In fact, WATER IS A GENUINELY BLUE CHEMICAL, although thin layers under 3ft do appear colorless. Water is very strongly colored in the infrared band, and the "tails" of the IR absorption curves spread into the visible spectrum, making water colored. As with window glass, if we look through a layer many feet thick, we'll discover its true color. To see the real color of any transparent substance, just hold a thick layer of that substance in front of a white background such as white beachsand or a swimming pool painted white. Here the white background is the white foam kicked up by the ship's props.

For the science behind water's blue color, see:

http://www.lsbu.ac.uk/water/vibrat.html

http://www.dartmouth.edu/~etrnsfer/water.htm#blue

http://en.wikipedia.org/wiki/Color_of_water

http://www.webexhibits.org/causesofcolor/5B.html


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[xXRonzellXx]

water is every color :o

[wbeaty]

@xXRonzellXx That's why it's blue!

Well seriously H2O is much like yellow food coloring. Ever notice that the Red, Green and Blue are those colors, but the Yellow food color bottle is dark orange? Wha? Water acts like that too. In shallow layers it's light turquoise or "seafoam-green," while in thicker and thicker layers it's bright blue, then blue-black.

Aerial photos of white caribbean beaches show this perfectly: bit.ly / uwxbbL

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[Sanotaru92]

what kind of water are you talking about? there is a lot of kinds of water, depending on the substances that are solved in... The des-ionized and Destiled water, I mean, H2O is aparently Transparent, but you got to make an emision specter!

[wbeaty]

@Sanotaru92 Water, obviously.

Not water+dirt or water+algae. Fresh water is blue. Distilled water is blue. DDW is blue.  You need >3ft thick before the color is visible. Blue indoor swimming pools with white sides.

Mineral coloration isn't very common. We see dissolved mineral colors in hotsprings, mine tailing streams, industrial waste ponds. Rarely in lakes, rivers, oceans.

[joyting]

Great video. I've learned something new today \o/. it's a pity that all of these things people keep saying in the comments are the same and can be disproved with an almost copy and paste answer.

[wbeaty]

@007s00s Don't be stupid. Even liquid mercury isn't 100% reflective. A shiny red car is very reflective, but it doesn't turn blue during sunny days, and neither does the ocean.

Water only acts reflective when light is glancing off at low angles, as when the surface looks bright red at sunset. To see the blue color of water, find photos of white swimming pools. In the Caribbean and tropical beaches the water's blue color is revealed because it's seen up against the white sand bottom.

[wbeaty]

@Sanotaru92 didn't bother to click on any of the links? Or click "SHOW MORE?"

Get educated. Their demo is with a several-meters pipe full of pure water. The blue color is obvious. The other site shows the absorption spectrum of pure water. It's not flat! Water is colored.

If you have an indoor pool with white sides and bottom, and fill it with water, why does it turn bright blue? Everyone says "it's reflecting the sky!" Lol, it's indoors. It's because water itself is blue. Always has been.

[Sanotaru92]

@wbeaty Distiled water is blue? Looool

[LongHairedAntelope]

@bastian74 the sun is white. you see a yellowish during day and redish during dusk and dawn because the rays of lights are being bounced through our atmosphere allowing only certain colors through

[wbeaty]

@bastian74 the sun is actually white. Go look upwards at noon in clear weather, and block the blue sky with your hands so it doesn't mislead.

But seriously, search on "land color theory," Edwin Land. During sunsets when the sun is red, paper still looks white. Brain processing allows eyes with color vision to see surface colors and ignore the illuminator wavelength bias.

[wbeaty]

@OllieWheats they probably learned it wrong during K-6 grade school. And... if school was this wrong about something so important and simple, why, that means *all of it* could be wrong. We thought we were living in 2010, but it's like we're still in the year 1500

Questioning your textbooks, it's called "critical thinking" and either turns you into a scientist who intentionally questions all assumptions, or perhaps knocks you entirely into distrusting paranoia against all authorities.

[bastian74]

Last comment tonight. I enjoyed flipping through your videos. Make more, it's been 2 years. Question:  Why is white paper white if you look at the sun directly and it's yellow? Shouldn't white paper be the same color as the sun? There should really only be one color of water, what varies with depth is attenuation.