HURRICANES: The Eye of The Storm

Chapter 7

What is a Hurricane?

Name given to violent windstorms of the Atlantic Ocean, The Carribben Sea, and the Gulf of Mexico

Different name in other regions Baguio (Philippines) Cyclone (Indian Ocean) Typhoon (Pacific Ocean)

Characteristics

Forms over large bodies of water Approximately 8 – 15 degrees North or

South of the Equator Can reach 800 km in diameter and height

of about 3 km Winds move in a circular motion around

the centre Centre is called the eye (calm sunny

region about 50 km)

Characteristics (cont.)

Move across land or water Wind rotate

Counter clockwise in Northern Hemisphere Clockwise in Southern Hemisphere

In Northern Hemisphere they travel northwest and than travel eastward

In Southern Hemisphere, they travel southwest and than travel eastward

Causes

Huge amounts of moist air above the ocean are heated by the sun

This causes the air to rise The warmer the ocean water, the greater

the amount of rising air Air is replaced by cooler, heavier air Blows inward in a spiral Starts as a tropical disturbance As wind speed picks up changes from

tropical disturbance to a hurricane

Types of Damages

Storm surges – sudden rises in sea level created by high

winds pushing water towards the land Along coastal areas

Hurricanes are fill of moisture so they cause a large amount of rain to fall Creating mudslides, flooding in low lying

areas, swollen rivers

Measuring Hurricanes

Saffir Simpson Scale Measures the intensity of the hurricane Gives the height above normal tides (storm

surges) Uses wind speed from 75 km/h – abvoe 248

km/h to identify the severity Beaufort Scale

Measures wind speed Velocity above 120 km/h are classified as

hurricane Scale ranges from 0 - 12

Hurricane Georges

September of 1988 Category 4 on the Saffir-Simpson Scale Over $2 billion property damage on

Puerto Rico Dominican Republic was hit by floods,

leaving 200 000 people homeless Blew itself out along the Gulf of Mexico

Hurricane Mitch

October of 1998 Strongest hurricane at 290 km/h through

the Atlantic basin Category 5 Began as a tropical disturbance in the SW

Carribean Sea Tremendous amount of rain over Centa

America Caused mud slides and floods Broke over Mexico