Tropical Cyclone
A tropical cyclone refers to a storm system, which is featured by a huge low pressure center, along with several thunderstorms that result in strong winds and flooding rain. Tropical cyclones are caused due to heat released as a result of rise in moist air, which causes condensation of water vapor in the moist air. They are a result of a different kind of heat mechanism than other types of cyclonic windstorms. This has led to their classification as warm core storm systems.
The term tropical denotes both the geographic origin of these cyclones, as well as their formation in Maritime Tropical air masses. A very interesting feature in this regard, is the fact that they form almost exclusively in the tropical regions of the earth.
The term cyclone is used to denote, to storms of such cyclonic nature, which are characterized by counterclockwise rotational action in the Northern Hemisphere, along with clockwise rotation in the Southern Hemisphere. A tropical cyclone is denoted by several other names, like tropical storm, hurricane, typhoon, tropical depression, cyclonic storm, and simply cyclone, depending upon its location, as well as strength.
Tropical cyclones may result in extremely powerful winds, along with torrential rain. They may also result in high waves, as well as damaging storm surge, apart from menacing tornadoes. Their formations usually take place, over large bodies of water; and tend to lose their strength, when they move over land. This is the main reason as to why coastal regions usually receive substantial damage from a tropical cyclone, whereas inland regions are saved from such strong winds.
However, heavy rains can result in substantial flooding conditions; and storm surges might cause heavy coastal flooding, which may reach up to 25 miles from the coastline. Despite their devastating effects on human populations living in coastal areas, tropical cyclones can also contribute towards, relieving of drought conditions. They are also known to carry heat and humidity away from the tropical regions.
This makes them a vital part of the global atmospheric circulation mechanism. As it is, tropical cyclones are very much helpful in maintaining equilibrium in the Earth’s troposphere, apart from maintaining a relatively stable, as well as warm temperature worldwide.
Many a time, tropical cyclones form when the atmospheric conditions, surrounding a weak disturbance in the atmosphere are favorable enough. Others are formed while other types of cyclones achieve tropical features. Tropical systems are thereby moved by way of steering winds in the troposphere. In case the conditions remain favorable, then the tropical disturbances intensify resulting in the development of an eye. Till date, it is not possible to artificially induce the dissipation of these systems with the help of the current technology.
Tornado
A tornado refers to a violent, rotating column of air. This column of air is in contact with both, the surface of the earth, as well as a cumulonimbus cloud or, in some cases, base of the cumulus cloud. Tornadoes are formed in several sizes but are usually in the form of a visible condensation funnel, with a narrow end touching the earth. It is most often encircled by a cloud of debris.
In most cases, tornadoes occur with wind speeds ranging between 40 mph to 110 mph. They are around 250 feet across and tend to travel a few miles before they get dissipated. In some cases, they would manage wind speeds of more than 300 mph and might stretch to more than a mile. They may stay on the ground for dozens of miles.
Tornadoes have been found to occur in almost every continent except for Antarctica. They are however, every common in the United States. They may also occur in south-central and eastern Asia, Southern Africa, northwestern and southeast Europe, southern Canada, east-central South America, New Zealand, as well as western and southeastern Australia.
A tornado might not necessarily be visible. However, the intense low pressures resulted by the high wind speeds, along with rapid rotation typically because water vapor in the air, to be visible as a funnel cloud or condensation funnel. There is however, some argument in terms of what exactly can be termed as a funnel cloud or condensation funnel.
According to the Glossary of Meteorology, a funnel cloud can be defined as any rotating cloud suspended from a cumulonimbus. Thereby it includes most tornadoes, by way of this definition. As it is, many meteorologists define a funnel cloud as a rotating cloud, which is not related to strong winds at the surface, and a condensation funnel is actually a very broad term for any type of rotating cloud below a cumuliform cloud.
Tornadoes have often been found to begin as funnel clouds with no relative strong winds around the surface. As it is, not all of such conditions evolve into tornadoes. However, many a time, tornadoes are found to be lead by a funnel cloud. In the majority of the cases, tornadoes come up with strong winds at the surface, where the visible funnel is still above the ground. It therefore becomes quite difficult to discriminate between a funnel cloud and a tornado from a distance.
At times, many tornadoes arise out of the same large-scale storm system. In case there is no break in activity, then it is referred to as a tornado outbreak. There are however, several other definitions.
A period characterized by several successive days along with tornado outbreaks in the same area, is referred to as a tornado outbreak sequence, which may at times, also be referred to as an extended tornado outbreak.
Squall Line
A squall line refers to a line of rigorous thunderstorms, which may form along or to the fore of a cold front. The term was used in the early twentieth century, as a synonym for a cold front. It consists of heavy precipitation, frequent lightning, hail, strong straight line winds, along with tornadoes and waterspouts. Ruthless weather conditions along squall lines may be expected in case, it reveals a line echo wave pattern or in case the line is in shape of a bow echo.
The best warning of the occurrence of severe weather conditions down a squall line is when it morphs into a line echo wave pattern. A line echo wave pattern is a special arrangement in a streak of convective squalls, which indicates the incidence of low pressure area along with the probability of large hail, damaging winds, and tornadoes. Along every curve of the line echo wave pattern is a meso-scale low pressure area. As it is, in response to the very strong outflow in southwest of mesoscale low, a section of this line bulges outside. This leads to the formation of a bow echo. It is behind this bulge, that there lies a mesoscale high pressure area.
The polar front theory was presented by Jacob Bjerknes, who derived it through a complex set-up of surveillance sites in Scandinavia at the time of the First World War. This theory suggested that the major inflow into the cyclone was concentrated down two lines of convergence, with one in advance of the low, whereas the other tailing behind the low. As it is, the trailing convergence zone has been referred to as a squall line or a cold front. The areas of rainfall and clouds would appear to be focused alongside this convergence zone. Concepts of frontal zones resulted into the notion of the air masses. It is noteworthy that the nature of a three dimensional structure in terms of a cyclone had been conceptualized after the expansion of the network of upper air during 1940s.
An organized area of thunderstorm activity reinforces the pre-existing frontal zones. Along with this, they can outrun the cold fronts. Such outrunning takes place in a pattern wherein the upper level jet cracks into two torrents. The ensuing mesoscale convective system structures at the point of an upper level split of the wind pattern in an area of the best low level inflow. Thereafter, the convection moves east and towards the equator in the warm sector and parallel to the low level thickness lines.
While the convection is tough and curved or linear, the mesoscale convective system is known as a squall line, along with the feature positioned at the foremost edge of the major wind shift and the pressure rise.
Mesocyclone
A mesocyclone denotes a vortex of air, which is around two to ten kilometers within a convective storm. So, it is air, which rises and keeps rotating around a vertical axis, generally in a similar direction as the low pressure systems of a given hemisphere. These are most usually cyclonic, i.e., associated with a restricted low-pressure area within a rigorous thunderstorm. Such storms may feature strong surface winds as well as severe hail.
Mesocyclones usually take place, together with the updrafts in case of supercells, where tornadoes might form. Mesocyclones are said to form when there are strong changes in wind speed or direction with height sets sections of the lower fraction of the atmosphere spiraling in the form of invisible tube like rolls. As it is, the convective updraft in case of a thunderstorm is thereafter believed to draw up this rotating air, leaning the orientation of the roll upward and resulting in the total updraft to revolve as a vertical discourse. Mesocyclones are usually relatively localized, i.e. they lie in between a synoptic scale and small scale. Radar imagery has been used for identifying such features.
Mesocyclones may also drop several tornadoes at one time, which spin around the parent funnel, just like spokes across a central wheel. The tornadoes tend to appear on right rear side of the supercells, thereby taking place where torrent of cold air from the downdraft twists into the main temperate air updraft.
It is not necessary that Mesocyclones should always produce tornadoes. According to an estimate, more than 1,500 mesocyclones strike United States each year, yet only half of them give rise to tornadoes. In case, the cyclones run out of warm, wet, surface air, they die out. In case they do not run out of their fuel, however, rotating cloud would stretch towards the ground and might become a giant tornado. It has been observed that tornadoes are probable to form when clouds look green or yellow, or in case the air is muggy or still after rain.
One of the best ways to detect, as well as verify the existence of a mesocyclone is through Doppler weather radar. Therefore, the word mesocyclone has been associated with the weather radar terminology.
Mesocyclones have most often been identified in right-rear flank of the supercell thunderstorms as well as squall lines and might be distinguished by way of a hook echo revolving signature on Doppler weather radar map. The visual cues like a rotating wall cloud or a tornado might also hint at presence of a mesocyclone.
Dust Devil
A dust devil refers to a well-formed, strong, and a relatively long-lived whirlwind, which may range from around half a meter width to over 10 meters width. The main vertical movement is upward. In most cases, dust devils are harmless, but in rare cases, they can grow up large enough to pose as threat to both people as well as property.
Dust devils are formed most frequently in the desert areas wherein the sun burns down on poorly conducting sand surface. They might also occur in case of non-vegetated areas like parking lots, particularly if they are accompanied by large buildings nearby to help in causing irregular air currents. As it is, hot deserts or parking lot surfaces heat up a thin cover of air just above, which sets up the stage for the formation of the dust devils.
The sudden uplift of hot air results in air to speed up horizontally inward towards the bottom of a newly-forming funnel. As it is, one of the principles of physics in terms of moving air is its vorticity getting preserved. The need that vorticity should be preserved results in a large speed up in circular motion of air, which spirals inward towards the bottom of this new funnel.
A dust devil, when fully formed, resembles a funnel type chimney through which movement of hot air takes place, both upwards as well as circular. As the hot air ascends, it cools down, loses its resilience and eventually stops to rise. As it ascends, it displaces the air that descends exterior to the core of vortex. The cool air returning tends to act as a kind of balance against the spiraling hot air outer wall as well as keeps the system stable.
A dust devil might last for less than a minute to several hours. The air may speed up to 70 mph a limit, which has been measured in case of vigorous dust devils. This helps them to pick up debris, leaves, dust and at times, rather large objects. These storms tend to get formed in groups. So, a large dust devil may sometimes be seen to be accompanied by little, shorter devils traveling alongside or behind it.
Dust devils are quite often compared with tornadoes in a sense that both of them are weather phenomenon in terms of rotating column of air of vertical orientation. Most of the tornadoes are linked with a bigger parent circulation, with the mesocyclone on back of the supercell thunderstorm.
The dust devils form up as swirling updraft under sun-drenched conditions through fair weather conditions, rarely coming close to an intensity of a tornado.
Tornado Warning
A tornado refers to a violent, rotating column of air. This column of air is in contact with both, the surface of the earth, as well as a cumulonimbus cloud or, in some cases, base of the cumulus cloud. Tornadoes are formed in several sizes but are usually in the form of a visible condensation funnel, with a narrow end touching the earth. It is most often encircled by a cloud of debris.
Tornadoes have been found to occur in almost every continent except for Antarctica. They are however, every common in the United States. They may also occur in south-central and eastern Asia, Southern Africa, northwestern and southeast Europe, southern Canada, east-central South America, New Zealand, as well as western and southeastern Australia.
A tornado might not necessarily be visible. However, the intense low pressures resulted by the high wind speeds, along with rapid rotation typically because water vapor in the air, to be visible as a funnel cloud or condensation funnel. There is however, some argument in terms of what exactly can be termed as a funnel cloud or condensation funnel.
A tornado warning refers to an alert, which is issued by the government weather services, in order to warn the inhabitants of an area that a tornado might be impending. It may be issued after a tornado or a funnel cloud has been spotted already, or in case, there are radar indications, which suggest that a tornado might be possible.
A tornado warning means that there is an immediate danger for the forewarned and the immediately surrounding areas from a severe thunderstorm forming up or likely to form. All the inhabitants, falling in the way of such a tornado are advised to take cover instantly, since it is a life-threatening condition. A warning must not be befuddled with a tornado watch, which only indicates those conditions, which are favorable in terms of the formation of tornadoes.
The first warning of a tornado was issued by meteorological staff of Tinker Air Force Base in the year 1948. It was also incidentally the very first successful tornado forecast, as well. Nowadays, tornado warnings are generated with the help of computers and then disseminated by way of various communication routes, which are accessed by media and the various agencies, on internet, to the NOAA satellites, and on the NOAA Weather Radio. The civil defense sirens have also been activated for affected areas if present.
Thunderstorm
A thunderstorm, or lightning storm, as it is also known as, refers to a weather condition, which is characterized by lightning, as well as its effect, i.e. thunder. It is typically accompanied by heavy rains and at times, snow, hail, or no precipitation at all. Thunderstorms might line up in the form of a series; and strong as well as severe thunderstorms may rotate.
As it is, warm air has a density, which is much lower than cool air; hence warm air rise within cooler air, displaying a phenomenon, witnessed in case of hot air balloons. Cloud formation takes place, when warm air carrying moisture ascends up within cooler air. When warm air goes up in the air, it cools down. Thereby, the moist water vapors begin to condense. When the moisture gets condensed, this releases energy, keeping the air warmer than its surroundings, so that it continues to rise. In case of presence of enough instability, in the atmosphere, the process continues for a period long enough for the formation of cumulonimbus clouds. This support lightning, as well as thunder.
Formation of a thunderstorm, irrespective of the type, goes through three stages, i.e. the cumulus stage, the mature stage, and the dissipation stage. These stages can take anywhere from 20 minutes to several hours to occur, depending on the conditions present in the atmosphere.
Thunderstorms take place throughout the world; in fact, even in the Polar Regions. They show the greatest frequency in areas covered by tropical rainforest, where they might take place, as often as everyday. Thunderstorms have been linked with the different monsoon seasons across the globe; and they occupy the rainbands of all the tropical cyclones. In case of temperate regions, they occur most frequently during springs and summer.
They may however, occur along or at times, ahead of the cold fronts during any time of year. They might also occur within a cooler air mass pursuing the channel of a cold front over a comparatively warmer water body. Thunderstorms are rarely to occur in Polar Regions, mainly due to cold surface temperatures.
A severe thunderstorm is the most devastating stage of a thunderstorm; and the term is used to denote a thunderstorm, which has arrived at a determined level of severity. Quite often, this level is evaluated by the storm, which is strong enough to cause wind or hail damage. As it is, in the Central Region of the United States National Weather Service, the hail verge for a severe thunderstorm is not until it is up to 1 inch in diameter. Although a funnel cloud or a tornado might indicate the presence of a severe thunderstorm, a warning of tornado would be issued in place of a warning for severe thunderstorm.
Bermuda Triangle Theories
The Bermuda triangle is a stretch over the Atlantic Ocean. Bordered by Florida, Bermuda, and Puerto Rico, the location became famous on account of the strange disappearances of ships, as well as aircrafts in the area. A number of supernatural explanations have been put forward in regard to the mysterious disappearances in this area.
However, many probable logical explanations for the missing vessels include hurricanes, earthquakes, as well as magnetic fields, which render navigation devices worthless. But, most people would not like to accept such boring explanations and would instead opt for more interesting options like alien abduction, or giant squids or getting sucked into another dimension. The following is a list of supernatural theories, which have been quite popular:
1.Presence of a time warp is one of the most popular theories of all times. With many people claiming to be lost in the time warp while going through the region; this theory was able to garner strength.
2.Another popular theory is that of alien abductions. According to it, the Bermuda Triangle is a collecting station where aliens take our people, ships, planes and other objects back to their planet to study.
3.Sea monsters are another popular theory, which has been quite popular. In fact, presence of sea monsters have been perhaps the most widely believed explanations for the strange disappearances, especially the earlier times, when the existence of sea monsters were widely believed to be true.
4.Another explanation for this, has been said to be death Rays from Atlantis. Those who believe in this explanation, state the presence of magic crystals, left from the time of Atlantis, deep down in the sea. It is said that rays from these crystals are responsible for the strange sinking of the ships. However, several underwater expeditions have revealed places under the ocean that look man-made, but no such crystals were found. In fact no real proof that Atlantis existed, was even found.
Apart from the above supernatural explanations, several natural explanations are also there. These include bad weather, sea piracy, giant whirlpools, presence of live bombs in the past, along with magnetic fields and methane gas formation. As it is, among all these theories, the theory in regard to methane gas formation appears to be quite believable. As it is, formation of methane can lower the density of water, leading to the sinking of ships. Similarly, Methane can cut out an aircraft engine with very little levels of it in the atmosphere, leading to aircraft crashes.
Whatever be the actual reason, it has always occurred to me that there is an involvement of more than one factor, behind the disappearances of ships and aircrafts the Bermuda triangle region.
Bermuda Triangle Survivors
The Bermuda Triangle is unavoidably associated with disappearances of aircrafts and vessels. Several theories in regard to the strange phenomenon have been put forward, which include time travel, UFO’s, missing time, as well as wormholes. Uncommon incidents have however been reported by several people, while they were on their way through the Bermuda triangle.
These witnesses constitute a long list of pilots, sailors and crew man, along with fishermen. It is interesting to note that none other than the great Christopher Columbus was also one to witness an uncommon phenomenon. The incident has been reported in his diaries. Christopher Columbus wrote in his memoirs on how his compass acted strangely while sailing through the Bermuda Triangle. He along with another shipmate witnessed a glowing globe of light that seemed to hover over the sea. Another major witness to such a phenomenon was Gerome Cook, the great sailor of the fifteenth century.
Several witnesses have reported a strange cloud or fog, hovering around the area. It is said that when strange clouds or fog enter the Bermuda Triangle, strange things start happening. Such a phenomenon has been witnessed with the Philadelphia Experiment in which the USS Eldridge vanished and reappeared later miles away, with some of the crew men wrapped into the hull of the ship. A number of incidents have been reported in the past, in regard to people disappearing into a strange mist around this area, without a trace. In 1901 Anne Moberly & Eleanor Jourdain stepped into a mist and claimed to arrive at a time period before the French Revolution. It is said, that the mist and the ominous clouds might be the key to time travel or entering other dimensions.
Great pilots like Charles Lindbergh have also said to witness this unusual phenomenon, while they were travelling through the Bermuda triangle. It is said that when Charles Lindbergh was making a nonstop flight from Havana to St. Louis his magnetic compass started rotating. His Earth-inductor-compass needle jumped back and forth erratically. This has now all been revealed in his autobiography. Even a great pilot like Charles Lindbergh witnessed unusual events while flying in the reaches of the Bermuda Triangle.
Another eyewitness account is that of Bruce Gernon, who flew his plane, a Bonanza A36 into the Bermuda Triangle and encountered a non-threatening mile and a half long cloud. As he neared, the cloud seemed to come alive. It became huge and engulfed his plane. However, a tunnel opened up in the cloud and he went through this tunnel. The tunnel had cloud trails swirling around his plane. He also reported that while going into this tunnel, he experienced zero gravity and the only thing keeping him in the cockpit was his seatbelt.
Such incidents are some of the few famous eyewitness accounts of people facing strange phenomenon in the area.
How the Bermuda Triangle Works
This mysterious place accounts fro more than 1500 disappearances, which include ships, boats, as well as aircrafts. The term “Bermuda Triangle” was first coined by a famous magazine in 1964. The mystery behind these disappearances has continued. As it is, several explanations have come up since the discovery of the dangers posed by these waters. These explanations range from supernormal phenomenon like giant squids, sea monsters, time warp, death rays from Atlantis, as well as alien abduction.
However, with the passage of time, fewer and fewer people now believe it to be a handiwork of any sea monster. Alien abduction however continues to be a widely believed phenomenon, along with presence of a time warp. However, some people have also come up with some scientific explanations as well. The following are some of the possible explanations for this strange phenomenon:
1.One of the scientific explanations states that, in the 1940s, navigating a plane involved relying completely on a magnetic compass to guide them. So, pilots had to be guided by their compass as they estimated how the wind would influence their planned flight path, in order to remain on the right track.
2.Another explanation revolves around a highly unpredictable weather. Now, since the island is situated in the Atlantic Ocean, it has an extremely unpredictable weather. So, it gets a weather, which is influenced by several factors and can change with lightening speed. That means that one moment you have a brilliant weather, whereas the other moment, you may be faced with an extremely perilous weather.
3.Also, another factor, can that be of hurricanes, which are very common in the Bermuda Triangle area. In this region, they generally originate from the African coast and flourish with the moisture of the warm, tropical waters, leading to creation of several destructive hurricanes. Along with it, you also have an additional peril in the form of thunderstorms. Several ship wrecks were caused due to the thunderstorms in the region.
4.Apart from these, another factor, which holds much strength, is the formation of methane in the sea. As it is, formation of methane can lower the density of water, leading to the sinking of ships. Similarly, Methane can cut out an aircraft engine with very little levels of it in the atmosphere, leading to aircraft crashes.
As it is, Bermuda triangle continues to evoke a lot of enthusiasm. Most people like to read about it. In fact, in the last few decades, Bermuda has emerged as a major tourist destination as well; mainly due to its close proximity with the Bermuda Triangle.
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