Eps 1: Why is the ocean blue?
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The ocean is blue because water absorbs colors in the red part of the light spectrum.
Like a filter, this leaves behind colors in the blue part of the light spectrum for us to see.
The ocean may also take on green, red, or other hues as light bounces off of floating sediments and particles in the water.
Host
Sonia Duncan
Podcast Content
When light hits the water surface, different colours are absorbed, reflected, permeated, scattered and scattered in varying intensities by the so-called optically active components of the water droplets. Blue wavelengths of light are scattered in a similar way to blue light from the sky. The reason the ocean often appears blue is because of the absorption or scattering of this light. Absorption is the process of scattering in clear seawater, rather than absorbing the light itself.
This absorption plays a crucial role in generating the blue color of the ocean, whereas this is not the case in the sky.
The blue colour of the ocean is due to the absorption of light in the form of visible light by the water surface. Blue light has shorter wavelengths to which our eyes are not very sensitive, so the blue colors must be at least half the wavelength of visible light, neglecting the wavelengths to which the eye is sensitive, such as red, green and blue.
The colors we see depend on the reflection of visible wavelengths of light through our eyes, and the color you see depends on the reflections of visible wavelength light in your eyes.
When sunlight hits the seawater, water molecules absorb the light rays in different ways: first they absorb light waves, then they scatter them by absorbing them, and then quickly again - and emit them in a different direction. While the red wavelengths are absorbed quickly, the blue wavelength is transferred to the greater depths of the ocean.
Mathematically, blue light has a wavelength of about 1.5 micrometers, or about the same wavelength as a human eye. The shorter wavelengths of the blue wavelength tend to reflect back to our eyes, but the longer wavelengths - the red and green wavelengths, such as the light of the sun - are mainly absorbed by the water molecules.
The appearance of a blue color in the ocean is due to the fact that seawater absorbs the red spectrum of visible light, but not the green spectrum.
When light falls on the water surface, different colors of water molecules are absorbed, reflected or transmitted or scattered at varying intensities in the so-called optically active components of the upper layer, the epipelagic photic zone of an ocean. Seawater absorbs almost 99 percent of red light, while orange and yellow light can be absorbed at 25 and 51 meters, respectively.
The fact that open seawater appears blue at noon on clear conditions is due to the absorption and scattering of light. Water molecules absorb almost all sunlight blue, so the absorption is much greater than the scattering in clear seawater. The wavelengths of the blue are scattered, similar to the scattered blue light from the sky. For this reason, the open oceans will look deep blue from space, but the reason for the blue color of the ocean.
Seawater contains a lot of phytoplankton, so it appears greener because it contains chlorophyll, which absorbs most of the blue part of sunlight.
When more phytoplankton is present, more blue and red light disappears, making the water appear green. More green light is reflected back into the ocean, giving algae-rich regions a greenish hue. Think of it as the green color of the chlorophyll contained in a leaf, but with more green and less blue light.
The humic material, which enters rivers through precipitation and soil, leaves behind a yellowish-brown color on the water surface, which is reflected back in the sea in the form of blue and red light. The more color - blue area is created by the place where sunlight hits the particles, not by the color of the water itself.
In other words, the colors in the sea and the color of the sky are independent, but related. In both cases, the red and reddish light from the sun and the blue light from the water lead to blue. Taken together, the light we see rising from an ocean is unabsorbed, backward-scattered light that, for much of this time at least, makes blue appear. When the white light of our sun enters the oceans, it turns blue, returning to us, and not the other way around.
Note that this effect only works when the water is very pure; when it is full of mud, algae or other impurities, the light scattered by these impurities will cover the water with natural blue. Have you ever wondered why seawater looks blue and why water in your cup looks clear to you?
White light from the sun is actually a mixture of red, green and blue light, and you can see it every time you see a rainbow. When sunlight passes through the water, the red part of the light is absorbed by water molecules. The absorption of this red light by the water molecules is similar to the way the pigment molecules in your blue shirt absorb red and green light and reflect or bounce off it so that we can all see the blue light.