When Mother Nature Paints A Masterpiece: Atmospheric Optics!
These natural events which are also known as 'Novaya Zemlya Effect,' 'Fata Morgana,' and 'Green Flash' are kinds of mirages.
A mirage is a naturally occurring optical phenomenon in which light rays are bent to produce a displaced image of distant objects or the sky.
Let's learn more about nature's magical optical illusions and how they come about.
The Novaya Zemlya effect is a polar mirage caused by high refraction of sunlight between atmospheric thermoclines.
This effect gives the impression that the sun rises earlier and sets later than usual. Depending on the meteorological conditions, the Sun looks like a flat, horizontal line or a rotated hour glass (known as rectangular Sun).
The mirage requires rays of sunlight to have an inversion layer for hundreds of miles and depends on the inversion layer's temperature gradient. The sunlight must bend to the Earth's curvature at least 250 miles (400 km) to allow an elevation rise of 5 degrees for the sight of the sun disk.
*__A thermocline (sometimes metalimnion in lakes) is a thin but distinct layer in a large body of fluid (e.g. water, such as an ocean or lake, or air, such as an atmosphere) in which temperature changes more rapidly with depth than it does in the layers above or below.
The first person to record this phenomenon was Gerrit de Veer, a group member of William Barents' third unfortunate polar excursion.
'Novaya Zemlya' means 'new world' in Russian and is also the name of the archipelago De Veer made this observation on.
An example of "Novaya Zemlya Effect" recorded during sun set:
'Green Flashes' take place right before sunrise or right after sunset.
A green spot is visible, usually for no more than a second or two, above the sun, or a green ray shoots up from the sunset point.
Green flashes are actually a group of phenomena stemming from different causes, and some are more common than others. Green flashes can be observed from any altitude (even from an aircraft).
Green Flashes coming from bright celestial objects such as the Moon, Venus or Jupiter are also observable on the horizon.
Fata Morgana, on the other hand is a rare, complex, and superior form of mirage; like many other kinds of superior mirages, is seen in a narrow band right above the horizon.
It is an Italian phrase derived from the vulgar Latin for 'fairy' and the Arthurian sorcerer Morgan le Fay, from a belief that the mirage, often seen in the Strait of Messina, were fairy castles in the air, or false land designed to lure sailors to their death created by her witchcraft.
Fata Morgana can cause objects to look quite distorted, so much that the objects look extraordinary and sometimes so different that it is impossible to identify them.
It can be observed on land, sea, in polar regions, and deserts.
The mirage comprises several inverted (upside down) and erect (right side up) images that are stacked on top of one another.
This optical phenomenon occurs because rays of light are strongly bent when they pass through air layers of different temperatures in a steep thermal inversion where an atmospheric duct has formed.
In still air, colder and more intense air layers can be observed on a milder temperature layer of air, which forms an atmospheric canal that creates rotated and distorted images by acting like a refractor lens.
In the photo on the left side, you can see the ship that looks like it is floating in the air. On the right side, however, it is the 'normal' image that was captured a couple of hours later.
On a closer look: it looks like there are flying ship experiments going on. 😦
It was also claimed that the phenomenon that took place in China last year could be Fata Morgana:
Mirages that were captured in 6 minutes, from the same location:
In the upper-most photo, you can see an inferior mirage of the Farallon Islands. In the second one, there is a Green Flash. The one in the middle and the one below show us the superior mirages of the Farallon Islands. This pattern is consistent with Fata Morgana.
Lastly, it is fair to say that this photo summarizes it all. You can see both the real and the fake image in one frame.
But when you look at it from a bigger distance, you can only see the mirage.
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