Hurricanes

A hurricane, also known as a tropical cyclone, is a severe storm system that has a low-pressure center and numerous thunderstorms that surround it, producing strong winds and heavy rainfall. Hurricanes occur when air with lots of moisture rises, causing condensation of water vapor and the release of heat. Since hurricanes use heat to fuel their destructive power, they are classified differently than nor’easters and European windstorms. Hurricanes usually originate at or near the equator, about 10 degrees from it (which is where the name ‘tropical cyclone’ comes from). They always develop and gain momentum over water and when they reach land, their power subsides. It is considered a cyclone because of the nature of the storm by which it always cycles in a counter-clockwise motion.

How Hurricanes Destroy While Helping at the Same Time:
Aside from containing high powered winds and heavy rainfall, hurricanes can also spawn other natural hazards, such as tornadoes and storm surges. The heavy rains can also lead to severe flooding in regions close to coasts that are hit by a hurricane. While hurricanes are dangerous and destructive to human and animal life, they are a natural part of the earth and actually aid in the atmospheric cycles that have been occurring over millions of years. Due to hurricanes, equilibrium in the earth’s troposphere is maintained, and in turn, assists in a generally warm and temperate climate all around the world.

Structure of a Hurricane:

The Eye and Eyewall:
At the center of a hurricane is what is referred to as the “eye” of the storm. This is an area of sinking air at the center of the circulating storm. The weather in this small region is generally calm and without clouds in the sky. The eye can be about 1 mile wide to 230 miles wide. Surrounding the eye is is the “eyewall”, a circular shaped set of thunderstorms, where the most powerful effects of a hurricane are found. It has extremely strong winds, high clouds, and high levels of precipitation. When the eyewall reaches land, this is the area of the hurricane that causes the largest natural disasters. The eyewall is also considered the heart of the hurricane because when it weakens, the rest of the tropical cyclone weakens as well.

Size:
Hurricanes are measured by determining the distance from the center of its rotation to the outermost “isobar”. If the distance is about 138 miles, it’s considered a very small hurricane; if the distance is 207 to 420 miles, it is average-sized; and if it is 552 miles or more it is considered very large.

When Hurricanes Occur:
Generally, the peak of “hurricane season” is usually during the summer time when the difference in temperature between air and the surface of the ocean is the greatest. But, each region on the earth has a different pattern of tropical cyclones. May is considered to be the most least active for hurricanes and September is the most active.