The Magnificent Atmospheric Optical Effects: Weird and Wonderful Oddities of Nature
Published by The world’s rainbow capital is Honolulu in Hawaii. The mountains on the windward side of the islands cause the prevailing warm, moist trade winds to rise, creating clouds and almost daily rain, and forming lots of rainbows.
The Magnificent Atmospheric Optical Effects: Weird and Wonderful Oddities of Nature
By Mr Ghaz, May 20,2010
The Magnificent Atmospheric Optical Effects: Weird and Wonderful Oddities of Nature
When sunlight strikes the atmosphere it is scattered, and sometimes split into its component colors, by water droplets, ice crystals and dust particles in the air, causing a variety of optical illusions.
Rainbows and fogbows are formed by the bending (refraction) of light by water droplets.
The Northern and Southern Lights (aurora borealis and aurora australis) that appear in the sky over the poles are caused by changed solar particles reacting with the atmosphere.
Intense heat can create mirages – optical illusions caused by refraction of light by heated layers of air close to the ground.
Rainbows and Fogbows
Image Credit
Raindrops bend (refract) light rays from the Sun, acting much like prisms by splitting the light into its seven component colors. Each color emerges again at a slightly different angle depending on its wavelength, producing separate bands of color. Red (the longest wavelength) appears on the outside of the rainbow, followed by orange, yellow, green, blue, indigo, and violet. The higher the Sun is in the sky, the flatter the rainbow. A double rainbow occurs when light is reflected within the raindrops.
When sunlight hits water droplets in fog an almost colorless fogbow results. The lack of color is due to fine water droplets of fog not dispersing light as well as larger droplets.
Green Flash
A green flash can occur at sunrise or sunset when some part of the Sun suddenly and briefly seems to change color from red or orange to green or blue. This is an optical effect caused by the larger refraction of light at the blue/ green end of the spectrum.
Weird and Wonderful
The world’s rainbow capital is Honolulu in Hawaii. The mountains on the windward side of the islands cause the prevailing warm, moist trade winds to rise, creating clouds and almost daily rain, and forming lots of rainbows.
Sun Effects
Rainbows are just one optical effect caused by sunlight passing through the air. Here are some more.
Halo: A circle of colored light appears around the Sun.
Parhelion (sundog, mock sun): A bright spot appears on either side of the Sun. Haloes and parhelia are caused by sunlight refracting through ice crystals in the atmosphere.
Corona: A circle of light round the Sun, caused by refraction through water droplets.
Iridescence: Light is diffracted into patches of brilliant color when it passes through thin clouds.
Sun pillars, subsuns: White streaks and discs appear above the Sun, caused by light being reflected by ice crystals rather than refracted through them.
Glory: A highly magnified shadow of someone stranding on a mountaintop is cast on clouds below by a low Sun. Sometimes the shadow is surrounded by bands of color, as happens on the German mountain Brocken, where it is called Brocken’s Spectre.
Crepuscular Rays: Alternating dark and light rays are caused when sunlight is split by an obstruction such as low cloud or a mountain.
Mirages
When sunlight passes through air layers of different temperatures and densities, it bends (refracts). On very hot surfaces, such as a desert floor or tarmac road in summer, the light is refracted upwards. This produces a false image (such as a sheet of water) just above ground level. Alternating layers of cold and warm air can produce complex mirages that look like buildings surrounded by water. They are called Fata Morganas, after the legendary Morgan le Fay who was said to live in a castle under the sea. One famous Fata Morgana appears in the Strait of Messina between Italy and Sicily.
Seeing Things: Layers of air at different temperatures bend the light, creating an image perceived by the viewer as floating above ground.
Aurora
These spectacular, shifting colors seen at high latitudes are caused by charged solar-wind particles entering the upper atmosphere and being deflected towards the Poles by the Earth’s magnetic field. As particles spiral down the magnetic lines of force they bombarded gas molecules, causing them to emit colored light.
Light Display: Dancing aurora lights illuminate the northern night sky.
Liked it
On November 5, 2009 at 4:22 pm
Great photos for a great article. These phenomena are fantastic and depend on the latitudes. So everyone will have theirs!
On November 5, 2009 at 5:15 pm
Another great article Mr g. Very informative and with wonderful pictures to go with it.
On November 5, 2009 at 5:53 pm
Wow thats amazing…
On November 5, 2009 at 7:01 pm
Your work is always spectacular Mr Ghaz!!This had some very interesting and educational facts for just about everyone on the planet! Excellent write!
On November 5, 2009 at 7:19 pm
Mr. Ghaz, I was astounded and overwhelmed as I read your article and the photo’s were absolutely amazing.
On November 6, 2009 at 2:11 am
Very informative piece with some beautiful pictures!
On November 6, 2009 at 4:44 am
Wow! A fantastic and very educational piece. Once again you have taught me so much. I alo love the illustrations. Great work.
Christine
On November 6, 2009 at 8:16 am
Ghaz: Coolest thing I’ve seen on the web in some time. Sparkling text, awesome photos.
On November 6, 2009 at 7:04 pm
An amazing display of natural wonders within these awesome pictures. Great article and very well done!
On November 6, 2009 at 10:29 pm
Interesting and superb pictures!
On November 7, 2009 at 2:59 am
Another awesome article..wonderful and stunning pictures..Well done Mr Ghaz!! Keep it up
On November 7, 2009 at 4:25 am
This is A-1 article. well presented and astonishing pictures.
On November 7, 2009 at 6:22 am
Just brilliant! An in-depth look at all these optical phenomena. We live on a wonderful planet.
On November 7, 2009 at 10:08 am
A good dose of interesting physics. Amazing photos too.
On November 8, 2009 at 1:50 pm
amazing pictures with great info!!
On September 26, 2010 at 9:27 pm
Wonderful!