Analysis of Thunderstorm - Report Example

Analysis of Thunderstorm Name Institution Course Date Introduction The world is characterized by severe weather conditions. Severe weather is any dangerous meteorological phenomenon that has the potential of causing damage, loss of human life or serious disruption to social life. These types of weather phenomena vary as it depend on altitude, atmospheric conditions, latitude and topography. Thunderstorm is a form and effect of severe weather. In general, severe weather is defined by meteorologists as any aspect of weather that threatens human life and property. It can also be described as any weather phenomena that relates to severe thunderstorms. Indeed, thunderstorm is one of the most devastating weather phenomena in United States. This report analyses thunderstorm as a weather phenomena and its consequences to aviation industry. Overview Thunderstorms are considered among the most destructive weather-related natural disasters. In comparison with hurricanes, the areas that are affected by thunderstorms are relatively small. A typical thunderstorm lasts for almost thirty minutes and its diameter is 15 miles (Alcorn, 2007). At any given point in time, almost 1,800 thunderstorms occur all over the world. This translates to 16 million thunderstorms being registered globally in a single year. Although thunderstorms are small in size, they are very dangerous. Basically, a thunderstorm is a cumulonimbus cloud that has developed to a level that it produces lightning (Alcorn, 2007). Therefore, the combination of lightning and thunder are responsible for many deaths each year. In fact, they kill more people than tornadoes. Flash flooding can be caused by heavy rains that are triggered by thunderstorms. Also, tornadoes, and strong winds are threats that are related to thunderstorms. In United States, nearly 10 per cent of all the thunderstorms that occur in a single year are categorized as severe (National Severe Storms Laboratory, 2016). A thunderstorm is considered severe by National Weather Service (NWS) when it produces tornadoes, wind of 58mph or hail that has a diameter of at least ¾ inch (Alcorn, 2007). However, there are several conditions that every thunderstorm needs regardless of its severity. Requirements of Thunderstorms Every thunderstorm requires moisture, lifting mechanism and unstable air (American Public Health Association, 2016). For thunderstorm to occur, there must be clouds and rains. Clouds lead to formation of rain that triggers thunderstorms. Before clouds and rain are formed, moisture must be present in the environment. This means that moisture is needed to formed thunderstorm. Unstable air is needed by every thunderstorm. Unstable conditions in the environment are created by a relative warm air near the earth surface and cool air at the middle of the troposphere (Alcorn, 2007). The general instability of air is increased by the near surface air that has high moisture content. The third incident that each thunderstorm needs is lifting mechanism. There are four active vital mechanisms in the environment that are responsible for lifting air near the ground. However, the processes that occur at the mid-level of the troposphere all the way to upper level can influence elevation of surface air. Orographic, frontal, convergence and convention lifting are four lifting mechanisms that cause elevation of air into the upper surface of earth. In other words, these are the four types of thunderstorms. Types of Thunderstorms Orographic lifting takes place when air that is flowing in a horizontal direction meets the surface of the earth. It is forced to move in upward direction in conformity with how land is elevated as shown below. This kind of lifting occurs everywhere as long as air is directed against increasing land elevations. However, this happen mostly in mountainous regions. On the other hand, frontal lifting happens when activities in the earth surface forces air to flow up from a less dense air mass to a denser air mass. This is illustrated in the figure below. Convergence lifting occurs slightly different from both orographic and frontal lifting. This lifting mechanism is as a result of air being forced to move towards each other. Air cannot move downwards near the surface of the earth as the surfaces of both earth and ocean act as physical barriers. Lastly, conventional lifting is caused by warm air that is heated near the ground. Daytime heating can significantly warm the surface of the earth especially during summer and in places that have low latitudes. The parcels of air that are in contact with the earth surface are warmed hence becoming less dense and starting rising. All the above features play an important part in formation of thunderstorms as it happen in stages. Stages of Thunderstorms Thunderstorm occurs in stages. Before thunderstorms develop, the direction of wind changes with height as the speed of wind increase with the increasing height. Hence, a spinning effect which is invisible in nature is created in the lower atmosphere. The rotating air is tilted from a parallel angle to vertical by rising air in the thunderstorm draft as shown below. At this point, the Developing Stage of thunderstorm starts. Indeed, thunderstorms occur in three stages; the developing stage or cumulus stage, the mature stage and the dissipating stage or decaying stage (NSSL, 2016). In the developing stage, thunderstorm is characterized by cumulus cloud that a rising air is pushing upwards. In a short while, cumulus cloud looks like a tower as rising air continues to build up. Occasional lightning occur during this stage but there is absence or little rain (NOOA, 2016). When the rising column of air continues to stir up the storm, as precipitation starts to decrease in the storm hence creating air that pushes downwards marks the start of mature stage of thunderstorm. The column of air that is pushing downward and air that has been cooled by rain spreads along the ground eventually forms ‘a line of gusty winds’ (NSSL, 2016). In the mature stage of thunderstorms, frequent lightning, heavy rain, tornadoes and strong winds are most likely to be experienced. At the end, production of significant amount of precipitation is realized and the rising column of air is overcome by line of air pushing downwards giving birth to dissipating or decaying stage. It is characterized by line of pair pushing downwards throughout the whole cloud (State Climate Office of North Carolina (SCONC), 2016). Dissipation often starts when the droplets of supercooled cloud freezes and the cloud contains ice crystals. The cloud then starts to collapse because of the absence of latent heat after cloud droplets are freezes out. Furthermore, dissipation of thunderstorm can be started when lifting stops, supply of moisture is no longer available or precipitation in the storm turns out to be too heavy (National Oceanic and Atmospheric Administration (NOAA), 2016). The intensity of rainfall decreases but lightning is still a danger at this stage. The three stages of air mass thunderstorms can be illustrated below. The first column depicts cumulus stage, second is mature stage, and the third denotes decaying stage. Types of Thunderstorms based on Structure There are several types of thunderstorms. They can be classified by their structure or severity. A thunderstorm is classified as severe if it either produces hail of 2.5 centimetres long, a tornado, or wind gusts of 93km/hr (National Weather Service, 2016). The damages caused by these types of storms can be so devastating. Thunderstorms can be classified by the basic building blocks that are known as cells. A cell is a region in a cloud that is compact and has a strong upright rising column of air. This give rise to various thunderstorms cells hence types of thunderstorms that include single cell, multi-cell and super-cell thunderstorms. Single-cell thunderstorms last for a short period of time and measures a few kilometers or miles in diameter. They exist for a period of not more than one hour (Borade, 2016). On the other hand, super-cell storms are larger in size and can last for many hours. It produces dangerous weather conditions in form of large hail, tornadoes, strong wind gusts or dangerous lightning. The severity of super-cell thunderstorms is primarily as a result of the manner in which the environment that storms form is structured. In order this kind of storm to occur, there must be strong vertical wind gusts and an atmosphere that is very unstable. Thunderstorms can also be multi-cell cluster or multi-cell line (squall line) types of storms. Most of the thunderstorms are multi-cell storms (Bureau of Metereology (BOU), 2016). Multi-cell storms are comprised of multiple individual single-cell storms, each one of them being a different stage of storm development: cumulus, mature, and decaying. Multi-cell storm can last for several hours depending as some cells can be in the decaying stage while others in cumulus stage. There is a moderate wind shear which tilts the storm hence preventing precipitation from falling into the rising column of air and absorbing it as in the case of single-cell thunderstorm. This is known as multi-cell line thunderstorm. It is also a severe storm composed of several single-cell storms. It is a complex of individual storms covering a large area. In most cases, multi-cell line storm forms in the late afternoon. A low-level inflow of moist air is required to form this kind of storm which has a life span of about six to twelve hours or more (BOU, 2016). It slowly develops and grows in size as moist air continually developing and maintaining thunderstorms. All over the world, thunderstorms take place in varied force. They mainly occur in the tropical rainforest regions (Borade, 2016). However, storms are also witnessed in the polar regions. Often, thunderstorms are associated with the start of monsoons (Borade, 2016). Indeed, it is associated with several other weather phenomena including lightning, flash floods and tornadoes. Thunderstorms are caused by warm, moist air that is present in cloud. A warm updraft is initiated when this kind of air in cloud rises with a greater velocity and large volumes forcing storm cloud to rise upwards. As a result, vapor is cooled and condensed forming water droplets and hail. It begins to descend, stoking rising column of air resulting in turbulence inside the cloud. A force is triggered causing cumulus clouds to erupt violently hence releasing electrical activity. Thunderstorm then occurs causing several effects depending on the nature of its severity. Effects of Thunderstorms Thunderstorms can cause a lot of damages. Indeed, several hazardous incidents in the world are associated with thunderstorms (NSSL, 2016). Flash flooding can occur as a result of rainfall from thunderstorms albeit under the right set of circumstances in the environment. It kills many people every year as compared to hurricanes and tornadoes (NWS, 2016). Lightning that is associated with thunderstorms causes many fires all over the world hence is responsible for a number of fatalities. The strong winds from thunderstorms uproot trees and power lines causing blackouts and damages to property and people’s homes. It may lead electrocution of people and animals. In general, thunderstorms have several effects. Thunderstorms have severe effects on human beings, animals and people. It includes deaths, electrocution, shock and massive destruction of property. One thunderstorm can result in heavy winds, rainfall, lightning, tornadoes, and hail. Of all these events, lightning is considered as the most dangerous and the worst (NWS, 2016). Scientists have attempted to understand how thunder and lightning combine in order to minimize its potential destructive effects. Nonetheless, thunderstorms continue to affect human beings in several fronts including general health and psychological well being of people. There have been scientific reports in Australia, Canada, and Great Britain about massive outbreaks of asthma attacks related to thunderstorms in the last thirty years (Andrews, 2012). One factor that ties thunderstorms to asthma is pollen. There is a popular theory that argues that whole pollens are carried into the storm cloud base by the rising column of air where they started breaking hence opening up into forms that are easier to inhale. When thunderstorms begin, the columns of air that is being pushed downwards (downdrafts) transport the pieces of pollen back into the ground level where are capable of easily triggering allergy and asthma symptoms (Andrews, 2012). The sound associated with thunderstorms also affects human ears. During a lightning storm, thunder occurs due to acoustical effect between high pressure and temperature (McDonaugh, 2016). Human ears are affected because of the significant change in pressure. The rumbling noise can cause impair hearing of an individual or worsen the situation of a person who already had a hearing problem. Aside from sound effect, thunderstorm also has a mechanical effect. Lightning strikes associated with thunderstorm are highly pressured and can cause damages to properties especially metallic objects. This pressure is so destructive when a lightning strike hits a tiny, closed area such as cracks in walls or a tree capillary. Indeed, a tree can be exploded when there is sufficient high pressure that passes through a capillary of a tree. Thunderstorms and Aviation Accidents Thunderstorms can lead to catastrophic airplane accidents. Indeed, all thunderstorms have characteristics that are hazard to aviation (Davies, 2014). However, not all thunderstorms have all hazards. On the other, the kind of hazards that a thunderstorm contains cannot be visually determined. All thunderstorms have potential hazardous turbulence which can lead to severe thunderstorms capable of destroying an aircraft. The strongest turbulence in the cloud occurs between the rising columns of air and downward moving column of air. In a thunderstorm, holding constant altitude is almost impossible. In an attempt to carry out this function by maneuvering, pilots greatly increase stress on the airplane. There is less stresses when an aircraft is held in an altitude that is constant. Lightning is often associated with thunderstorms. The skin of an airplane can be punctured by a lightning strike (NSS, 2016). As a result, damages to communications as well as electronic navigational equipment can occur. This may lead the aircraft to crash. Indeed, there are several aviation accidents that have been directly caused by thunderstorms. In 2014, thunderstorms led to disappearance of AirAsia Flight 8501 aircraft that had 162 people on board (Davies, 2014). Eventually, the aircraft was found out with no survivors. This accident illustrates how dangerous thunderstorms are to aviation industry. The losses are massive especially human lives that are terminated because of aircraft accidents associated with thunderstorms. Aviation industry is also seriously affected due to loss of revenues occasioned by a crashed airplane. Although modern aircrafts are capable of withstanding bad weather conditions and fly with one engine for some hours, there are many occasions severe thunderstorms have led to airplane crashes or cancellation of flights. Additionally, today’s airliners can repel lightning strikes and high level of turbulence (Davies, 2014). Given these remarkable characteristics of modern aircrafts, one might wonder the reasons behind the great threats that thunderstorms pose and why pilots continually attempt to avoid this natural phenomenon. This is because thunderstorms combine almost all the hazards that pilots fear (NWS, 2016). Of all the hazards that aviation industry faces, thunderstorms contain it all. It includes engine icing, structural icing, wind gusts, lightning, turbulence and loss of visibility. Aviation industry is not immune to lightning strikes. Specifically, airplanes are capable of being stroked by lightning with certain frequency. Flight Safety Foundation estimates that a commercial aircraft is hit by lightning at least once a year- this is not considered a serious issue. Nonetheless, this issue is given some serious attention in the industry by subjecting aircraft to artificial lightning during the testing period. This ensures that the plane is capable of withstanding lightning and not poses a threat to passengers and airplane crew. Ice associated with thunderstorm is particularly dangerous (Davies, 2014). Structural damages to an airplane can be caused by hail that shoots from the apex of a thunderstorm. Ingesting large quantities of ice crystals can result in flaming out of jet engines although pilots can restart them. However, this has led to crashing of airplanes. For example, in June 2009, Air France 447 crashed killing all the passengers and crew due to blockage of tubes by ice crystals albeit in part. The pilots did not respond in a correct manner after the ice crystals pushed the aircraft computer to change to manual control from autopilot. Thunderstorms have been and continue to be a major threat to aviation industry. It has led to loss of many lives and destruction of billions of dollars worth property through destruction of planes and collateral damages caused by airplane crashes. Several measures have been carried out to minimize, avoid or eradicate the effects associated with thunderstorms. Modern meteorologists and radar equipment can spot thunderstorms to a great length of accuracy. In United States, FAA has the ability to track thunderstorms 6 to 8 hours before it happen (Davies, 2014). They thus assign different routes in order to avoid these dangerous occurrences. By using radar, pilots are capable of seeing heavy precipitation from a distance of more than 100 miles. They thus avoid them by either flying around them or fly over them depending on its severity. Indeed, airplanes occasionally fly over thunderstorms. This may depend on an airline that specifies what course of action is taken in case of storms. Conclusion Thunderstorms are common natural occurrences in United States. All thunderstorms that occur in the country are dangerous. A number of hazards that have caused a lot of damages and losses in the past are associated with thunderstorms. Heavy downpours can result in massive flash floods. In fact, it is the main cause of deaths occasioned by thunderstorms. Lightning is also related to thunderstorms. In fact, every thunderstorm produces lightning. Lightning is responsible for an average of eighty (80) deaths and three hundred injuries every single year (Center for Food Security and Public Health, 2016). Also, lightning can cause damages to expensive electrical equipment, start building fires and electrocute both humans and animals. Additionally, it is the number one cause of several farm fires witnessed all over the world. Thunderstorms generate high winds which in turn cause damages to homes, trees by uprooting them, and overturn vehicles. Crops and property are yearly damaged by hail resulting in billions of dollars worth of losses to farmers. Hail can also inflict injuries to people or animals that are left outdoors. References Alcorn, M. (2007). ‘Thunderstorms’. [Online] Available: http://www.met.tamu.edu/class/atmo202/Severedir/severe-wx-stu.html. American Public Health Association. (2015). ‘Types of Disasters and their Consequences’. [Online] Available: http://www.medscape.com/viewarticle/513258_12. Andrews, L.W. (2012). ‘How Thunderstorms Affect Health’. [Online] Available: https://www.psychologytoday.com/blog/minding-the-body/201206/how-thunderstorms-affect-health. Borade, G. (2016). ‘Causes and Effects of Thunderstorms’. [Online] Available. http://www.buzzle.com/articles/causes-and-effects-of-thunderstorms.html. Bureau of Metereology. (2016). ‘Thunderstorms’. [Online] Available. http://www.bom.gov.au/storm_spotters/handbook/thunderstorms.shtml. Centre for Food Security and Public Health. (2016). SEVERE THUNDERSTORMS’. [Online] Available: http://www.prep4agthreats.org/Natural-Disasters/thunderstorms. Davies, A. (2014). ‘AirAsia Flight 8501: What Makes Thunderstorms Such a Threat to Airliners’, [Online] Available: http://www.wired.com/2014/12/airasia-qz8501-thunderstorms/. McDonaugh, J., (2016). ‘The Efffects of Lightning on Humans & Nature’. [Online] Availabe: http://www.ehow.com/info_8545584_effects-thunder-lightning-humans-nature.html. National Oceanic and Atmospheric Administration. (2016). ‘Severe Thunderstorms and Tornadoes: What is a Thunderstorm and How Does it Form?’ [Online] Available: http://www.wrh.noaa.gov/fgz/science/svrwx.php. National Severe Storms Laboratory. (2016). ‘Thunderstorm Basics’. [Online] Available: http://www.nssl.noaa.gov/education/svrwx101/thunderstorms/. National Weather Service. (2016). ‘Thunderstorms, Tornadoes, Lightning…:Nature’s Most Violent Storms’. [Online] Available. http://www.nws.noaa.gov/om/severeweather/resources/ttl6-10.pdf. State Climate Office of North Carolina. (2016). ‘Life Cycle of a Thunderstorm’. [Online] Available: https://climate.ncsu.edu/climate/tstorms/lifecycle.php. Read More

This means that moisture is needed to formed thunderstorm. Unstable air is needed by every thunderstorm. Unstable conditions in the environment are created by a relative warm air near the earth surface and cool air at the middle of the troposphere (Alcorn, 2007). The general instability of air is increased by the near surface air that has high moisture content. The third incident that each thunderstorm needs is lifting mechanism. There are four active vital mechanisms in the environment that are responsible for lifting air near the ground.

However, the processes that occur at the mid-level of the troposphere all the way to upper level can influence elevation of surface air. Orographic, frontal, convergence and convention lifting are four lifting mechanisms that cause elevation of air into the upper surface of earth. In other words, these are the four types of thunderstorms. Types of Thunderstorms Orographic lifting takes place when air that is flowing in a horizontal direction meets the surface of the earth. It is forced to move in upward direction in conformity with how land is elevated as shown below.

This kind of lifting occurs everywhere as long as air is directed against increasing land elevations. However, this happen mostly in mountainous regions. On the other hand, frontal lifting happens when activities in the earth surface forces air to flow up from a less dense air mass to a denser air mass. This is illustrated in the figure below. Convergence lifting occurs slightly different from both orographic and frontal lifting. This lifting mechanism is as a result of air being forced to move towards each other.

Air cannot move downwards near the surface of the earth as the surfaces of both earth and ocean act as physical barriers. Lastly, conventional lifting is caused by warm air that is heated near the ground. Daytime heating can significantly warm the surface of the earth especially during summer and in places that have low latitudes. The parcels of air that are in contact with the earth surface are warmed hence becoming less dense and starting rising. All the above features play an important part in formation of thunderstorms as it happen in stages.

Stages of Thunderstorms Thunderstorm occurs in stages. Before thunderstorms develop, the direction of wind changes with height as the speed of wind increase with the increasing height. Hence, a spinning effect which is invisible in nature is created in the lower atmosphere. The rotating air is tilted from a parallel angle to vertical by rising air in the thunderstorm draft as shown below. At this point, the Developing Stage of thunderstorm starts. Indeed, thunderstorms occur in three stages; the developing stage or cumulus stage, the mature stage and the dissipating stage or decaying stage (NSSL, 2016).

In the developing stage, thunderstorm is characterized by cumulus cloud that a rising air is pushing upwards. In a short while, cumulus cloud looks like a tower as rising air continues to build up. Occasional lightning occur during this stage but there is absence or little rain (NOOA, 2016). When the rising column of air continues to stir up the storm, as precipitation starts to decrease in the storm hence creating air that pushes downwards marks the start of mature stage of thunderstorm. The column of air that is pushing downward and air that has been cooled by rain spreads along the ground eventually forms ‘a line of gusty winds’ (NSSL, 2016).

In the mature stage of thunderstorms, frequent lightning, heavy rain, tornadoes and strong winds are most likely to be experienced. At the end, production of significant amount of precipitation is realized and the rising column of air is overcome by line of air pushing downwards giving birth to dissipating or decaying stage. It is characterized by line of pair pushing downwards throughout the whole cloud (State Climate Office of North Carolina (SCONC), 2016). Dissipation often starts when the droplets of supercooled cloud freezes and the cloud contains ice crystals.

Read More