“For it is a land of illusion, a place in the mind, a shimmering mirage of riches and mystery and death. These illusions have distorted its landscape and contorted its history.” ~~Richard E. Lingenfelter
Current Weather:
-15°C|5°F Temperature
-22.9°C|-9.3°F Wind Chill
Skies: Mostly Clear
Visibility (miles): Unrestricted
Winds (knots): N @ 9
Station Pressure: 29.539 in.
Fata Morgana. It sounds like the title to a horror flick, an on the edge of your seat, heart stopping, hair curling film. But…it’s not.
It’s simply a mirage of something: an object or a landscape altered by shifting light and radiating air waves coming off of a landscape. You can most commonly experience this phenomenon either in a desert, ocean, or polar landscape. I had never heard of fata morgana let alone experienced a “vision/mirage” until I arrived in Antarctica. The first time I witnessed one, I found myself standing out at the Ice Runway squinting into the bright glare of the sun, wondering if I had just imagined that the distant mountain range, the Royal Society Mountains, had suddenly grown, swallowing up what had once been a flat expanse of sea ice.
Another word for Fata Morgana is phantasmagoria.
It’s simply a mirage of something: an object or a landscape altered by shifting light and radiating air waves coming off of a landscape. You can most commonly experience this phenomenon either in a desert, ocean, or polar landscape. I had never heard of fata morgana let alone experienced a “vision/mirage” until I arrived in Antarctica. The first time I witnessed one, I found myself standing out at the Ice Runway squinting into the bright glare of the sun, wondering if I had just imagined that the distant mountain range, the Royal Society Mountains, had suddenly grown, swallowing up what had once been a flat expanse of sea ice.
Another word for Fata Morgana is phantasmagoria.
phan·tas·ma·go·ria
noun \(ˌ)fan-ˌtaz-mə-ˈgȯr-ē-ə\
1: an exhibition of optical effects and illusions
2: A) a constantly shifting complex succession of things seen or imagined B) a scene that constantly changes
3: a bizarre or fantastic combination, collection, or assemblage
noun \(ˌ)fan-ˌtaz-mə-ˈgȯr-ē-ə\
1: an exhibition of optical effects and illusions
2: A) a constantly shifting complex succession of things seen or imagined B) a scene that constantly changes
3: a bizarre or fantastic combination, collection, or assemblage
The next few blog entries are going to be dedicated to wildlife and Antarctic specifics instead of philosophical ramblings. The season is winding down and there’s minimal time left for blogging, but I thought I’d try to get in what I could since I’ve slacked so much over the last few months. I apologize if these entries aren’t as interesting as the last few. But…it’s still a glimpse into life here on the ice.
In the words of Wikipedia a fata morgana is: an unusual and complex form of mirage which 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 sorceress 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 mirages distort the object or objects which they are based on significantly, often such that the object is completely unrecognizable. A Fata Morgana can be seen on land or at sea, in polar regions or in deserts. This kind of mirage can involve almost any kind of distant object, including boats, islands, and the coastline.
Here at McMurdo the fata morganas that I have gotten to witness have often occurred across the sea ice as I am driving toward the Ice Runway or out to the Pegasus Airfield. You’ll be driving along staring out at the mountains and suddenly realize that they have shifted to the left or to the right. The glaciers flowing out of the mountain valleys have suddenly gotten bigger or seem to be standing up like a wall of land and ice in front of you. The buildings out at Pegasus or LDB (The Long Duration Balloon Facility) suddenly seem like sky scrapers, standing tall silhouettes in the sky. The military LC-130’s tail fins are stretched out and wavering in the air, almost as if they had been made of silly putty and someone had put them through a pasta maker.
 |
| A "fata morgana" I was able to capture with my camera one morning |
It’s trippy. People call it a mirage, or a vision. You’ll find yourself sitting there wondering if there’s something wrong with your eye sight or if someone had slipped something into your morning orange juice. But no, it’s simply the Antarctic landscape dancing to its own rhythm.
This optical phenomenon occurs because rays of light are bent when they pass through air layers of different temperatures in a steep thermal inversion where an atmospheric duct has formed. A thermal inversion is an atmospheric condition where warmer air exists in a well-defined layer above a layer of significantly cooler air. This temperature inversion is the opposite of what is normally the case; air is usually warmer close to the surface, and cooler higher up.
In calm weather, a layer of significantly warmer air can rest over colder dense air, forming an atmospheric duct which acts like a refracting lens, producing a series of both inverted and erect images. A Fata Morgana requires a duct to be present; thermal inversion alone is not enough to produce this kind of mirage. While a thermal inversion often takes place without there being an atmospheric duct, an atmospheric duct cannot exist without there first being a thermal inversion.
A Fata Morgana is most commonly seen in polar regions, especially over large sheets of ice which have a uniform low temperature. Ta-da!! This might explain their common appearance here at McMurdo. They can however be observed in almost any area. In polar regions the Fata Morgana phenomenon is observed on relatively cold days, however in deserts, over oceans, and over lakes, a Fata Morgana can be observed on hot days.
This optical phenomenon occurs because rays of light are bent when they pass through air layers of different temperatures in a steep thermal inversion where an atmospheric duct has formed. A thermal inversion is an atmospheric condition where warmer air exists in a well-defined layer above a layer of significantly cooler air. This temperature inversion is the opposite of what is normally the case; air is usually warmer close to the surface, and cooler higher up.
In calm weather, a layer of significantly warmer air can rest over colder dense air, forming an atmospheric duct which acts like a refracting lens, producing a series of both inverted and erect images. A Fata Morgana requires a duct to be present; thermal inversion alone is not enough to produce this kind of mirage. While a thermal inversion often takes place without there being an atmospheric duct, an atmospheric duct cannot exist without there first being a thermal inversion.
A Fata Morgana is most commonly seen in polar regions, especially over large sheets of ice which have a uniform low temperature. Ta-da!! This might explain their common appearance here at McMurdo. They can however be observed in almost any area. In polar regions the Fata Morgana phenomenon is observed on relatively cold days, however in deserts, over oceans, and over lakes, a Fata Morgana can be observed on hot days.
 |
| Another shot I was able to capture. You can see the squiggles the fata morgana created at the base of the mountains. |
To generate the Fata Morgana phenomenon, the thermal inversion has to be strong enough that the curvature of the light rays within the inversion layer is stronger than the curvature of the Earth. Under these conditions, the rays bend and create arcs. An observer needs to be within or below an atmospheric duct in order to be able to see a Fata Morgana.
A Fata Morgana can be described as a very complex superior mirage with more than three distorted erect and inverted images. Because of the constantly changing conditions of the atmosphere, a Fata Morgana can change in various ways within just a few seconds of time, including changing to become a straightforward superior mirage.
Fata Morgana mirages are visible to the naked eye, but in order to be able to see the detail within them, it is best to view them through binoculars, a telescope or a telephoto lens. With a Fata Morgana it can be hard to say which individual segment of the mirage is "real" and which is not real: when a real ship is out of sight because it is below the horizon line, a Fata Morgana can cause the image of it to be elevated, and then everything which is seen by the observer is a mirage. On the other hand, if the real ship is still above the horizon, the image of it can be duplicated many times and elaborately distorted by a Fata Morgana.
Here, where there are patches of open water now that some of the sea ice has broken up, on cold sunny days, the patches of open water have appeared to look as if they have risen above the edge of the sea ice and are resting suspended in air. It’s interesting to be driving along and look out and see a bright blue pool of water quivering in the air above a bed of white.
A Fata Morgana can be described as a very complex superior mirage with more than three distorted erect and inverted images. Because of the constantly changing conditions of the atmosphere, a Fata Morgana can change in various ways within just a few seconds of time, including changing to become a straightforward superior mirage.
Fata Morgana mirages are visible to the naked eye, but in order to be able to see the detail within them, it is best to view them through binoculars, a telescope or a telephoto lens. With a Fata Morgana it can be hard to say which individual segment of the mirage is "real" and which is not real: when a real ship is out of sight because it is below the horizon line, a Fata Morgana can cause the image of it to be elevated, and then everything which is seen by the observer is a mirage. On the other hand, if the real ship is still above the horizon, the image of it can be duplicated many times and elaborately distorted by a Fata Morgana.
Here, where there are patches of open water now that some of the sea ice has broken up, on cold sunny days, the patches of open water have appeared to look as if they have risen above the edge of the sea ice and are resting suspended in air. It’s interesting to be driving along and look out and see a bright blue pool of water quivering in the air above a bed of white.
Some images I found on Youtube of Fata Morgana in the Arctic
Our landscape here is simple, yet not. We live in a world of white and blue. It’s been just over four months since I arrived here. It’s still the same landscape, yet it has changed so much and every morning as I make my daily commute out to the ice runway, I still find myself glad I’m here. It’s a beautiful, mystical landscape.
No comments:
Post a Comment