Hurricanes A-level :: essays research papers

Ø  Ã‚  Ã‚  Ã‚  Ã‚  The Caribbean region and the South Eastern United States of America are regularly subjected to the impact of tropical hurricanes; (A)  Ã‚  Ã‚  Ã‚  Ã‚  Briefly outline characteristics of such hurricanes. The hurricanes that occur over the Caribbean region and the United States of America usually eventuate between August and October. For these hurricanes to occur the surrounding ocean temperatures must be minimal, also there must be a prolonged spell of equable temperature, pressure and humidity in the lower troposphere in conjunction with anti-cyclonic conditions in the upper troposphere. These conditions cause intense low pressure and strong winds at the earth’s surface. For their to be enough energy for the hurricane to move, it is essential that there is a considerable source of heat. This is necessary to maintain a consistent supply of rising air in the form of currents. There needs to be a large supply of moisture, as it is necessary for condensation to take place in order to release latent heat and it is the latent heat that initiates the development of the storm and consequently produces heavy rainfall. When the hurricane reaches its maturity an eye develops in the centre, in the eye there is a relative area of subsiding pressure. Which is what causes clear skies, anomalous high temperatures and light winds. Eventually the eye disappears as a result of the descending air increasing instability, which in turn warms and increases the storms intensity. Around the eye there are towering Cumulo-nimbus clouds. The hurricanes decline as soon as the source of heat is lost/or removed. Although it can take between 9 and 15 days for this to happen. Winds immediately around a hurricane’s ‘eye’, which is usually about 32km (20 miles) across, reach more than 300 km/h (190 mph). But in the eye itself seen in the centre of the spiral-the weather is clear and calm. (B)  Ã‚  Ã‚  Ã‚  Ã‚  Identify the various types of damage caused by the passage of these hurricanes CATEGORY 1   Ã‚  Ã‚  Ã‚  Ã‚  Winds 118-152 Km/hour (64-82 Knots). Damage primarily to shrubbery, trees, poorly constructed signs, and unanchored mobile homes. No significant damage to other structures.   Ã‚  Ã‚  Ã‚  Ã‚  Storm surge 1-1.5m above tide. Low lying coastal roads inundated, minor pier damage, some small craft in exposed anchorages torn from moorings. CATEGORY 2   Ã‚  Ã‚  Ã‚  Ã‚  Winds 154-176 Km/hour (83-95 Knots). Considerable damage to shrubbery and tree foliage; some trees blown down. Extensive damage to poorly constructed signs. Major damage to exposed mobile home. Some damage to exposed mobile homes. Some damage to roofing materials of buildings; some window and door damage.