![]() The colors result from a combination of Rayleigh and Mie scattering.Īs light passes through the atmosphere, most of the shorter blue wavelengths are scattered leaving the majority of longer waves to continue. Some of the most picturesque clouds occur close to sunrise and sunset when they can appear in brilliant yellows, oranges and reds. Related: Meteotsunamis on the Great Lakes? Here's what they are and how they form Rayleigh and Mie If there is no direct sunlight striking the cloud, it may reflect the color of the sky and appear bluish. And as clouds thicken, sunlight passing through the cloud will diminish or be blocked, giving the cloud a grey color. Yet, clouds do not always appear white because haze and dust in the atmosphere can cause them to appear yellow, orange or red. The result is equally scattered 'white' light from the sun and therefore we see white clouds. ![]() Mie scattering does not differentiate individual wave length colors and therefore scatters ALL wave length colors the same. When the droplets and light waves are of similar size, then a different scattering, called 'Mie' scattering, occurs. Unlike Rayleigh scattering, where the light waves are much smaller than the gases in the atmosphere, the individual water droplets that make up a cloud are of similar size to the wavelength of sunlight. ![]() If the sky is blue, why are clouds white? Therefore, we perceive the blue color of the sky. The volume of scattering by the shorter blue light waves (with additional scattering by violet and indigo) dominate scattering by the remaining color wavelengths. Next, blue light waves scatter at a rate about four times stronger than red light waves. Indigo color light waves scatter next and can be seen from high altitudes such as jet airplanes flying at normal cruising altitudes. Yet, this scattering is not in equal portion but heavily weighted toward the shorter wavelengths.Īs sunlight enters the atmosphere much of the violet light waves scatter first but very high in the atmosphere and therefore not readily seen. The color of the sky is a result of scattering of ALL wavelengths. This is called Rayleigh scattering, named after Lord Rayleigh. The atoms and molecules comprising gasses in the atmosphere are much smaller than the wavelengths of light emitted by the sun.Īs light waves enters the atmosphere, they begin to scatter in all directions by collisions with atoms and molecules. So, if sunlight is ‘white’, why is the sky blue? Rainbows are partly the result of sunlight refraction through a rain drop, which acts like a prism. The end result is a dispersion of light into a rainbow of colors. The lowest energy light waves refract the least, while the highest energy waves exhibit the greatest refraction. The degree of refraction varies with the energy level each wave. The velocity of light decreases slightly as it moves into the prism, causing it to bend slightly. One way to see the colors of sunlight is by the use of a prism. This means the light waves that make up violets, indigo and blue have higher energy levels than the yellow, orange and red. The colors change as the wavelength increases from violet to indigo to blue, green, yellow, orange, red and deep red.Īs a light wave's length increases, its energy decreases. White light combines all of the colors in the 'visible spectrum', which is the range of colors we can see.Įach color in the visible spectrum represents electromagnetic waves of differing lengths. The Earth's natural source of light is the sun which provides 'white' light. The color of a cloud depends primarily upon the color of the light it receives. Here's a great explanation from the National Weather Service: The Color of Clouds ![]() There’s nothing more beautiful than a glorious sunset, especially when different colors are dancing in the skies.īut what do those colors mean and why do we see only certain colors? It starts with sunlight and science takes it from there.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |