Atmospheric Conditions Favorable for the Development of a Hurricane - Essay Example

The energy of a hurricane can be looked at in two ways: i) the total amount of energy produced by cold water condensation (cloud/rain formation). A mean/average hurricane produces 1.5 cm per day of rain inside a circle of radius of 665 km. More rain falls in the inner part of the hurricane around the eyewall and less in the outer rain bands. Converting this to the volume of rain provides 2.1 x 10^16 cm3/day. A cubic centimeter of rain weighs 1 gram. Using the latent heat of condensation, the amount of rain produced gives 5.

2x10^19 joules/day or 6.0x10^14 watts. This amount of energy produced is equivalent to 200 times the worldwide electrical generating capacity. ii) The amount of kinetic energy (wind energy) produced to maintain the strong winds of the hurricane (Camargo and Adam 2996). For a massive hurricane, the amount of wind energy (kinetic) generated is equal to that being dissolute due to friction. The dissolution rate per unit area is given by air density multiplied by the drag coefficient and the wind speed cubes.

Using 40 ms (90 mph) winds on a scale of the radius of 60 kilometers provides a wind dissipation rate of 1.3x10^17 joules/day or 1.5x10^12 watts. This is equal to about 1/2 the entire world electrical generating capacity. Either method generates enormous amounts of energy. The energy produced by hurricanes that maintain the hurricane’s spiraling winds is a ratio of 400 to 1. Most of the heat produced in the condensation process is consumed to cause rising motions/movements in the thunderstorms and only a small portion drives the storm’s horizontal winds.

The most recognizable feature within a hurricane is the eye. Found between 20 and 50 km in diameter, the eye is found at the center. In fact, the eye is the focus of a hurricane. It is the point where the rest of the storm circulates and where the lowest surface pressure is found in the hurricane, not to mention it is the calmest section of a hurricane. It is calm because the cariole force diverts the wind faintly away from the center, resulting in the wind rotating around the center of the hurricane, leaving the eye calm.

The average diameter (size) of the eye of a hurricane is 30-65 kilometers. It forms when the wind speeds reach 138km/hr. The near-surface wind field of a hurricane is characterized by air rotating fast around the center of circulation while at the same time flowing radially inwards. The outer-edge air may be calm because of the earth’s rotation. As the air flows inwards, it begins to rotate cyclically i.e. counterclockwise in the northern hemisphere and clockwise in the southern hemisphere to conserve angular momentum.

This radius is coincident with the inner radius of the eyewall and has the strongest near-surface winds of the hurricane. A hurricane is a system with established winds of at least 74 mph or 34 meters per second (119 km/h). The maximum sustained winds in the strongest hurricanes have been estimated at about 195miles/h(314 km/h) or 85 meters per second. The wind is a result of forces trying to balance. The pressure lowers in the center as the air spiraling around the eye must spin faster to offset the greater ‘slope’ (gradient) of the pressure surface (Chang, Liu, and Kuo1150).

The central pressure and pressure tendencies i.e. rising, falling or no change is a good gauge for hurricane strength today and in the near future. Lower pressure corresponds to higher winds so that a hurricane with 935mb worth of central pressure will be a bigger one while one with 990 mb central pressure will likely be a weak hurricane. The average duration of a hurricane is around 10-12 hours per region. It can move further and longer and it might take lesser time in some areas. The inrush of warm, moist air into the center of the hurricane as it weakens and ‘fills’ must be accompanied by arising motion above the storm.

So, as the storm weakens more cloudiness and precipitation occurs. However, in addition, more rainfall occurs due to topographic lift in hilly areas, as well. In the summer, the ocean surface warms/heats up and moist air rises. Cool air lowers down to replace it. This leads to the creation of a low-pressure area. The earth's rotation creates winds around the center of such low-pressure areas. The warm air rises in large masses and cools to create large dark clouds. Thunderstorm forms as it starts to rain (Hart and Jenni 911–913).