BALL LIGHTNING On August 17, 1978, a group of Soviet climbers camping in the Caucasus Mountains was attacked by ball lightning. The fireball flew into their sleeping bags one by one. One person died, four received severe burns. There are a lot of interpretations of the phenomenon of ball lightning - from UFOs and certain life forms to scientific hypotheses. P. L. Kapitsa believed that a standing electromagnetic wave arises between the clouds and the ground and a gas discharge can form on it, which moves along the field lines. There is a version of a plasmoid, thermochemical effects occurring in saturated water vapor under a strong electric field, etc.
Light pillars Light pillars (solar pillars) are an optical phenomenon that represents bands of light extending up or down from a bright object, for example, the Sun. Most often they can be observed during sunrise or sunset. A column of light occurs when sunlight reflects off the surfaces of tiny ice crystals suspended in the air. Such crystals form in high cirrus clouds, most often in cirrostratus clouds. At low temperatures, such crystals can also form in lower layers of the atmosphere. Therefore, light pillars are more often observed in the cold season.
Halo Halo is the refraction and reflection of light in the ice crystals of the upper clouds; They are light or rainbow circles around the Sun or Moon, separated from the luminary by a dark gap. Halos are often observed at the front of cyclones and can therefore serve as a sign of their approach
ST. ELM'S FIRE. If the electric field strength in the atmosphere is high, then in addition to spark discharges - lightning - sometimes there is an outflow of electricity from the ends of sharp objects. This phenomenon is explained by the fact that the air near protruding objects becomes a conductor of electricity and a glow appears at their sharp ends. These "quiet" discharges are sometimes accompanied by a faint crackling sound and are called the fires of St. Elmo, the patron saint of sailors. It is especially beautiful when St. Elmo's lights appear at the ends of the masts and yards of a sailing ship. These mysterious lights do not require thunderclouds to form; they are more often seen in the mountains, as well as during dust storms and blizzards.
Red Elves Elves are huge but faintly luminous flash cones (most often curved cones) that appear directly from the top of a thundercloud (anvil). They appear above the active system (core) of a thunderstorm and are directly associated with strikes of linear and plane lightning. They are red oval or cone-shaped spots that can be located above the cloud either in groups or individually. Elves are very tall, their tops rise to an average height of 95 km.
Gloria Gloria (from Latin gloria - glory, halo) is an optical phenomenon that consists of multi-colored rings around the observer’s shadow cast on a cloud consisting of water droplets. Gloria is similar to a rainbow, but it is much smaller than the colorful companion of rain. Its angular size ranges from 5 to 20 degrees, so it is almost always a complete circle. There is no exact theory of the formation of gloria, however, it is believed that, like a rainbow, it is formed due to the diffraction of light reflected by water drops.
MIRAGE (FATA MORGAN) Mirages are an optical phenomenon caused by the refraction of light rays in the atmosphere due to uneven heating of the air. They come in several types. Fata Morgana is the rarest type of mirage. It occurs when several alternating layers of air of varying densities are formed, capable of giving specular reflections.
The Northern Lights are not a terrestrial phenomenon because they are caused by the Sun and occur high above the earth. Periodically, a flare occurs on the Sun, equal in released energy to the explosion of an unimaginable number of atomic bombs, and a mass of particles is thrown into space, rushing at the speed of light. Deflected by the Earth's magnetic field, they strike atmospheric particles, imparting an electrical charge to them. Getting rid of the charge, the particles begin to “glow” - this process gives light, creating a show in the night skies. And the reason that the lights have chosen the polar regions lies in magnetic fields: they deflect particles rushing towards the equator and direct them towards the Earth's magnetic poles.
The phenomenon, known as "swaying curtains", occurs at an altitude of about 113 km. Maximum height at which lights are formed, km. above the earth's surface; There is also some indication that reddish lights are more common in the upper layers, where the atmosphere is thinner and particles are less likely to collide. As particle collisions become more frequent, the color changes to purple; at low altitudes the most common color is green. Although these dancing lights have been scientifically explained, they have retained an aura of mystery and a reputation as one of nature's most spectacular phenomena.
Presentation on the topic "20 most unusual natural phenomena" in geography in powerpoint format. This presentation for schoolchildren describes unusual phenomena found in nature, such as lunar rainbows, mirages, halos, northern lights and others. All phenomena are illustrated in the work. Author of the presentation: Kiseleva L. A.
Fragments from the presentation
Moon Rainbow
We are almost used to the usual rainbow. A lunar rainbow is a much rarer phenomenon than a rainbow that is visible in daylight. A lunar rainbow can only appear in places with high humidity and only when the Moon is almost full. The photo shows a moonbow at Cumberland Falls in Kentucky.
Mirages
Despite their prevalence, mirages always evoke an almost mystical sense of wonder. We all know the reason for the appearance of most mirages - overheated air changes its optical properties, causing light inhomogeneities called mirages.
Halo
Usually, halos occur when there is high humidity or severe frost - previously, a halo was considered a phenomenon from above, and people expected something unusual.
Belt of Venus
An interesting optical phenomenon that occurs when the atmosphere is dusty is an unusual “belt” between the sky and the horizon.
Pearl clouds
Unusually high clouds (about 10-12 km), becoming visible at sunset.
Northern lights
Appears when high-energy elementary particles collide with the Earth's ionosphere.
Colored Moon
When the atmosphere is dusty, high humidity, or for other reasons, the Moon sometimes appears colored. The red Moon is especially unusual.
Lenticular clouds
An extremely rare phenomenon, appearing mainly before a hurricane. Opened just 30 years ago. Also called Mammatus clouds.
St. Elmo's Fire
A fairly common phenomenon caused by increased electric field strength before a thunderstorm, during a thunderstorm and immediately after. The first witnesses to this phenomenon were sailors who observed St. Elmo's lights on masts and other vertical pointed objects.
Fire whirlwinds
often form during fires - they can also appear over burning haystacks.
Mushroom clouds.
They also form over places with elevated temperatures - over forest fires, for example.
Light pillars.
The nature of these phenomena is similar to the conditions that cause the appearance of a halo.
Diamond dust
Frozen water droplets scattering the light of the Sun.
Fish, frog and other rains.
One of the hypotheses explaining the appearance of such rains is a tornado that sucks out nearby bodies of water and carries their contents over long distances.
Virga.
A phenomenon that occurs when ice crystals fall from clouds that do not reach the surface of the earth, evaporating along the way.
Bora
Hurricane winds have many names. They arise when air masses move from the upper layers to the lower ones.
Fire rainbow.
Occurs when sunlight passes through high clouds.
Green beam.
An extremely rare phenomenon that occurs at sunset or sunrise.
Ball lightning.
There are many hypotheses explaining the origin of these phenomena, but none have been proven yet.
Optical flares and jets
Only recently discovered due to their short existence (less than a second). Occurs when hurricanes occur.
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A rainbow is an atmospheric optical and meteorological phenomenon observed when many water drops are illuminated by the Sun. A rainbow looks like a multi-colored arc or circle made up of the colors of the spectrum. These are the seven colors that are customarily identified in the rainbow in Russian culture, but it should be borne in mind that in fact the spectrum is continuous, and its colors smoothly transition into each other through many intermediate shades.
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A halo is a light, rainbow-colored ring around the sun. This vertical circle occurs when there are many hexagonal ice crystals in the atmosphere that do not reflect, but refract the sun's rays like a glass prism. In this case, most of the rays are naturally scattered and do not reach our eyes. But some part of them, having passed through these prisms in the air and refracted, reaches us, so we see a rainbow circle around the sun. Its radius is about twenty-two degrees. It happens even more - forty-six degrees. Halos are the surest sign of worsening weather. And if in winter white crowns of large diameter appear around the sun or moon, as well as pillars near the sun, or the so-called false suns, then this is a sign of continued frosty weather.
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Any of us has seen the simplest mirages. For example, when you drive on a heated asphalt road, far ahead it looks like a water surface. And this kind of thing has not surprised anyone for a long time, because a mirage is nothing more than an atmospheric optical phenomenon, thanks to which images of objects appear in the visual zone that under normal conditions are hidden from observation. This happens because light is refracted when passing through layers of air of different densities. In this case, distant objects may appear to be raised or lowered relative to their actual position, and may also become distorted and acquire irregular, fantastic shapes.
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Fata Morgana (from Italian - the fairy Morgana, according to legend, lives on the seabed and deceives travelers with ghostly visions) is a rarely encountered complex optical phenomenon in the atmosphere, consisting of several forms of mirages, in which distant objects are visible repeatedly and with various distortions. Fata Morgana occurs when several alternating layers of air of different densities are formed in the lower layers of the atmosphere (usually due to temperature differences), capable of giving mirror reflections. As a result of reflection, as well as refraction of rays, real-life objects produce several distorted images on the horizon or above it, partially overlapping each other and quickly changing in time, which creates a bizarre picture of Fata Morgana.
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Aurora (northern lights) - the glow of the upper layers of the atmospheres of the planets. Modern scientists believe that the lights in the sky are caused by the collision of electrically charged solar particles and atoms from our atmosphere - the energy from the collision is released in the form of light. The fact that the northern lights are observed mainly at the poles is explained by the fact that the Earth's magnetic field is especially strong there.
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A rare optical phenomenon - the “Ghost of Brocken”: a person standing on a hill or mountain, behind whom the sun rises or sets, sees that his shadow falling on the clouds becomes incredibly huge. This happens because tiny drops of fog refract and reflect sunlight in a special way. The phenomenon got its name from the Brocken peak in Germany, where, due to frequent fogs, this effect can be regularly observed
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St. Elmo's Light is a bright glow caused by the build-up of electrical discharge during a thunderstorm. This phenomenon can be observed on the masts and yards of ships, around an airplane flying through a cloud, sometimes on the top of a mountain peak. The flame does not burn or cause fire; the duration of this phenomenon is no more than a minute. Sometimes it is accompanied by a hissing or whistling sound.
Usually a thunderstorm occurs on a hot summer day. A strong wind rose, rain poured, lightning flashed, thunder rumbled. Why does a thunderstorm occur? Warm air with water vapor rises quickly. The higher you are from the Earth's surface, the lower the air temperature (see Shells of the Earth), so water vapor turns into water droplets and small ice crystals. Water drops and ice hailstones collide with each other, receiving an electrical charge. The resulting charges accumulate in the cloud, reach a certain power and are discharged with a bright flash - lightning. Lightning heats the air very strongly, it quickly expands and a blast wave occurs - we hear thunder. Light travels much faster than sound, so lightning is seen first, and only then thunder sounds. Based on the time interval between lightning and thunder, you can judge the distance to the thunderstorm: the later the thunder sounds after the flash, the further away the thunderstorm is.
