Mie scattering is caused by excess dust in the air , water droplets, pollen, or smoke in the lower atmospheric layers. Mie scattering occurs when the particles that cause the scattering are larger in relation to the wavelength of radiation. The angle of the sun and Rayleigh scattering also influence yellow cloud formation.
Rayleigh scattering is related to the chemical composition of the atmosphere and occurs the particles that cause the scattering of light are very small in relation to the wavelength of the light. Often during forest fires, yellow smoke emits, which is then directly reflected within the clouds up above, causing a yellowish tint in the clouds. Excess atmospheric nitrogen dioxide also causes yellow clouds; yellow clouds are more common in urban cities with high air pollution levels.
Once suspected to be an optical illusion, green clouds have long been paired with a hail storm or a tornado. It turns out, a greenish cloud is not necessarily a sign of either, despite some interesting folklore. However, the exact cause of green clouds is still subject to debate today.
Many scientists believe that the green tint comes down to the electromagnetic spectrum and the way particles absorb and reflect sunlight. According to one theory, the water droplets in the thunderstorm clouds absorb red light and make the scattered light appear blue.
When blue particles or objects are illuminated with red, the net effect is a green shade. Another theory states that the thunderstorm clouds remove all other wavelengths by acting as a filter, for the green waves to shine. Pink clouds are quite common in some parts of the world, while rare or totally absent in others.
They appear mostly sunset and sunrise. In certain areas of the world , especially highly polluted metro cities, the clouds will take a brighter pink to red shade — all thanks to the high concentration of aerosols in the atmosphere. Aerosols are emitted from automotive vehicles, excess dust, sandstorm, or forest fires. So, deserts, and urban areas with higher traffic are likely to witness pink clouds than any other places.
A professional writer, editor, blogger, copywriter, and a member of the International Association of Professional Writers and Editors, New York. He has been part of many reputed domestic and global online magazines and publications. In areas with a lot of haze, you don't typically see the types of sunsets that are likely to appear on a wall calendar— or in, say, National Geographic.
You see bright ones in the fall and winter particularly, especially in the East, because the air along the path of the ray of sunlight tends to be dryer and cleaner. I grew up in Baltimore, and this is part of why I got interested in weather.
I would wonder: Why is the sunset so pretty tonight? And there weren't answers to questions like this in standard weather books, because it's more about physics than forecasting. Speaking of forecasting, what about the saying: "Red sky at night, sailor's delight; red sky in morning, sailors take warning. Those spectrally pure colors are telling you there's a sizable swath of clear air off to your west that's likely to be over you the next day.
Yeah, you can forecast them to a certain degree. I guess it's a question of who cares—maybe filmmakers or photographers would find that information useful, but most people just want to know if it's going to rain or not. There's often a slanting band of clouds on the back side of the departing weather system, and that can act as a sort of projection screen for the low-sun colors, better than a horizontal band would. The slant means it captures more of the orange and red light, and if the cloud is thin enough, it will reflect those colors down to you.
Also, storms wash a lot of the big particles out of the air. Yes, true sunset occurs a minute or so before you see the sun disappear. What you see is a kind of mirage; the light is getting bent around the horizon by the effect of refraction.
Our eyes are sensitive to a very tiny part of the spectrum of the sun's wavelengths, and that's responsible for the way we see our environment. Other creatures seem able to see the ultraviolet area of the spectrum.
We can only see a tiny part of what's going on. So a butterfly or a reindeer , which can perceive ultraviolet light, might be seeing a different, perhaps more colorful sunset than we do? The more you look at things, the more you realize how unique your own experience is as a human on this planet, at this particular place and time. All rights reserved. In simple terms, what makes a good sunset happen? Do dust and air pollution make sunsets more dramatic? Do the seasons affect sunsets?
So conversely, could local weather forecasters predict a pretty sunset? Why are sunsets sometimes more dramatic after a major storm? Is it true that by the time we see a sunset, the sun is actually already gone? Sounds like there's a lot of science to sunsets, but it's also a very subjective experience.
This interview has been edited and condensed. Follow Amanda Fiegl on Twitter. Share Tweet Email. Read This Next Wild parakeets have taken a liking to London. Animals Wild Cities Wild parakeets have taken a liking to London Love them or hate them, there's no denying their growing numbers have added an explosion of color to the city's streets.
Thunder clouds are very dense and dense clouds have no intrinsic colour. Light rays are multiply scattered by their water droplets and so the wavelength dependence of angular scattering that, in very thin clouds, gives rise to iridescence or the colours of coronae is averaged out. Thick cloud colours result only from those of the light incident upon them be it the reds of sunset, the blues of the summer sky or the greens and earths reflected from the ground.
Two effects produced this cloud's pinks.
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