Hurricanes as a Natural Phenomena - Research Paper Example

?Hurricanes Introduction Hurricanes are one of the major disasters that can kill thousands of people in an instant. It is one of the most ferocious and devastating natural phenomena.Hurricane is part of family of storms called tropical cyclone.Tropical disturbances such as clusters of thunderstorms accelerate the process by generating a column of rising air in the zone of low pressure. Pushed by the trade winds, the disturbance becomes a spinning mass of thunderclouds growing as warm moist air sweeps in below the low pressure void. Due to the earth’s Coriolis Effect, the cloud mass always rotates counterclockwise in the northern hemisphere. As wind speed exceeds 74 miles per hour a hurricane is born. Hurricanes usually formed from warm water in the tropical region. Water is usually 800F (270C) in this part of the earth. In a year, four hurricanes develop in the Atlantic region and an approximate of sixty hurricanes rise from tropical seas and swirls through the globe. Coastal areas are the most prone to danger because hurricanes are formed in the sea. Hurricanes in the United States mostly come from the tropical and subtropical waters of the Pacific Ocean, the Gulf of Mexico, the CaribbeanSea and the Atlantic Ocean. Some are small and others are large. But whatever the case, hurricanes are the mightiest of all storms. Hurricanes are natural phenomena that can be dangerous and destructive but is perfectly designed by nature to serve a purpose. It is essential to maintain the optimal warm temperature of the earth. Hurricanes suck up warm water from the sea surface to its eye wall and when it rise up it condenses forming rains showers. These rain waters arid lands and alleviates drought in some hot locations. Anatomy of a Hurricane Hurricanes do not occur everywhere in the world. You can never find hurricanes in cold locations like the Antarctic and Arctic regions of the earth. Hurricanes start from storm seeds mainly from the west coast of tropical areas like the Pacific Ocean, Caribbean Sea, Gulf of Mexico and the Atlantic Ocean. Small atmospheric disturbance occur that creates low pressure area. Air is pushed through this low pressure area by the surrounding high pressure environment. Warm tropical sea water transfer heat to air so it rises as it nears the center. It speeds up the acceleration of rising air thus providing energy for the developing storm. Hot air then comes into contact with cold air aloft and results into thunderstorms. If the conditions are favorable like locations with high humidity and hot weather, a hurricane is most likely being formed. Low pressure systems with accompanying thunderstorms are called tropical cyclones. These tropical cyclones rotate counter clockwise in the northern hemisphere and clockwise in the southern hemisphere. This cyclonic behavior is due to the earths Coriolis Effect. Tropical disturbance is reported for a group of thunderstorms in the tropics that are present for at least 24 hours. It is then escalated to tropical wave status when it reaches winds with 25mph moving in all direction. The time it develops circulation, that’s the time it is called a tropical cyclone. Tropical depression is a tropical cyclone with wind speeds of at least 38 mph. When the tropical cyclone’s wind reaches 39 to 73 mph, it is then labeled tropical storm. Tropical storm has showers and thunderstorms that are moving closer to circulation. Hurricane is termed for the most severe category of tropical cyclone with maximum sustained winds of 74 mph. At this level, an eye is developed at the center of the cyclone. The coverage of the thunderstorms varies depending on the intensity and wind speed of the hurricane. Source: http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/hurr/stages/home.rxml Hurricanes have area that is relatively cloudless and calm. This area is called the eye of the hurricane and it is located at the center of the tropical cyclone. The eye is usually 20 to 30 m wide for a storm that has diameter of 400 miles across. The area immediate to the eye is called the eye wall. This is composed of dense clouds where the storms most violent wind occurs. Eye and eye wall structure can affect the hurricane’s wind speed and intensity. When the eye was reduced in size, double eye wall might form. Bands of numerous spiral thunderstorms circulate right before the eye wall. This are called rain bands. Rain bands with tropical storm-force winds can range up to few miles to ten of miles wide and 50 to 300 miles long. Force winds of a hurricane can extend outward up to 25 miles above the seas level for a mall hurricane and to more than 150 miles for a large one. Storm-force wind can stretch up to 400 miles from the center of a large hurricane. The right side of the hurricane is considered the most dangerous in terms of winds, storm surge and tornadoes it incurs. Hurricane covers a wide range of spot in a weather map and it travels in unpredicted nonlinear path. The hurricane’s eye is the spot monitored by weather administration to pose warning systems for locations affected by the weather disturbance. When the winds from a tropical cyclone reach 39 mph it was given a name. Saint’s name is used in the West Indies as attributed for the date the hurricane occurred. At the start of World War II, storms are designated with female names. In 1951 the United States name storm by phonetic alphabet (Able, Baker, Charlie) but they found it confusing. Nations weather services use female names for tropical cyclonesfrom 1953 until 1978. In 1979, both male and female names were included in lists for the Atlantic and Gulf of Mexico. Source: Hurricane Life Cycle Warm waters of African coast are the birth place of many hurricanes in the Atlantic region. Tropical cyclones emerge over these waters from intensified pre-existing tropical disturbances. These disturbances emerge every three to four days as tropical waves that consist of areas of unsettled weather. There are three main factors that determine tropical cyclone formation. These are pre-existing disturbance with thunderstorms, warm ocean temperatures (at least 800 F to a depth about 150 feet and light upper level winds that is frilly constant throughout the depth of the atmosphere, termed as low wind shear. Energy for the developing storm is gathered by the disturbance when it comes in contact with warm ocean water. Winds over the ocean stirred in spiral into the disturbance’s low pressure area. Rising air was added with heat and moisture by the warm ocean waters. Moisture then condenses and more heat is released contributing additional energy to power the storm. Atthis stage, bands of thunderstorms form, and the storm's cloud topsrise higher into the atmosphere.If the winds at these high levels remain relatively light, the storm can remain intact and continue to strengthen. Hurricanes and weather disturbances do not last for long. A week or two has been the longest reported case yet. There are many factors that contribute to storms end or decay. High wind shear can tear the hurricane apart. When the hurricane makes landfall, they normally weaken. Hurricanes moisture source is halted and spinning sustainability is reduced due to friction when it passes over land. Passing through cooler water or drier areas can lead to weakening as well. Possibility of re-intensification of hurricane may occur when it moves into region with high humidity or mid-latitude frontal systems. Hurricane Observation Two hurricane observation methods have been established today. Direct observation and Indirect observations make it possible for humans to follow activities of a tropical cyclone. Direct measurements of a tropical cyclone are taken using a reconnaissance aircraft that records data of hurricane dimensions and wind speeds. Ships and buoys are also employed to take measurements. Automated Surface Observation Systems (ASOS) give reports as with the condition of the hurricane when it is approaching or has landed. Indirect observational method makes use of advance technology employing satellite survey and imagery as well as Doppler radar. Satellite monitoring greatly improve the way humans monitor hurricane movement and intensity. Radar data are used for weather forecast when hurricane has come close offshore or has landed. Hurricane intensity is measured using the Saffir-Simpson Hurricane classification. In this classification, hurricanes are classified according to their maximum sustained speed or wind speeds. Numbers from 1 to 5 is used with 1 being the slowest with 74 to 95 mph wind speed and 5 being the highest and most dangerous with 456 mph wind speed. Another scale use to measure hurricanes and weather disturbances is Beaufort scale. Unlike the Saffir-Simpson scale, the Beaufort scale includes measurements for casual breezes and zero wind. Hurricane probabilities References Websites: http://www.usatoday.com/weather/hurricane/history/probabilities-table.htm http://www.washingtonpost.com/wp-srv/weather/hurricane/info/explainer.htm http://www.nhc.noaa.gov/ http://science.howstuffworks.com/nature/natural-disasters/hurricane4.htm http://stormcarib.com/climatology/ http://www.usatoday.com/weather/hurricane/stories/2001/2001-07-19-hurricanes-amm.htm Videos: http://video.about.com/geography/All-About-Hurricanes.htm http://www.youtube.com/watch?v=HJydFJORWf4 Read More