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Different Kinds of Weather. By : Jehda White. What is a Hurricane. A hurricane is a type of tropical cyclone. It can be up to 600 miles wide and have strong winds at speeds of 75 to 200 mph. A hurricane can last for a week.
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Different Kinds of Weather By : Jehda White
What is a Hurricane • A hurricane is a type of tropical cyclone. • It can be up to 600 miles wide and have strong winds at speeds of 75 to 200 mph. • A hurricane can last for a week. • Can move 10-20 miles per hour over the open ocean. • The center of the hurricane is the calmest part. It is called the eye. • The eye has only light winds and fair weather. • The low level storm winds blow counterclockwise around the eye.
life cycle of hurricanes • Tropical Depression A tropical disturbance that develops a closed circulation and is blowing around a center of low pressure in the Northern Hemisphere is called a tropical depression. This can contain maximum sustained winds of 38 miles per hour or less on the surface. • Tropical Storm A disturbance is called tropical storm once its winds are between 39 to 73 mph. The system is given a name by the National Hurricane Center. • Hurricanes A storm is classified as a hurricane once its wind field has sustained winds of greater than 73 miles per hour.
How Hurricanes Form • Hurricanes do a important job for the Earth. • Help move heat from warm tropical places to the cooler temperate zones. • They form 5 to 15 degrees latitude north and south of the equator. • Happen when the oceans have been warmed during summer months • Most hurricanes happen in the fall.
Storm Surge • One of the most dangerous parts of a hurricane is a storm surge. • When a hurricanes winds spiral around the storm, it can push water into a mound at the storms center. • This can become dangerous when the storm reaches land because it could cause flooding. • Hurricanes can cause more storm surges in areas where the ocean floor slopes gradually.
What are Tornadoes ….. • A tornado is a violent, dangerous, rotating column of air. • Tornado’s rotation appears to happen when winds are at two different speeds. • If a tornado gets caught in an updraft, it tightens the spin and speeds up. • The rain and hail in the thunderstorm cause the funnel to touch down creating a tornado.
How Tornadoes Form • First it starts in a thunderstorm called a super cell. • Super cells can last longer than a regular thunderstorm. • Wind that is coming into the storm starts to swirl and forms a funnel. • Air in the funnel can spin faster and faster. It can create a very low pressure area. • Tornadoes can form anytime during the year, but most form during May. • They cause most damage in April.
Where do Tornadoes Form • In a region called Tornado Alley which is located in the Great Plains. • Occur in the late afternoon and early evening hours. • They are most common from 4pm to 9pm
What are Tsunamis…… • It is a series of waves travelling across the ocean due to a sudden displacement of a large body of water. • Caused by events such as undersea earthquakes, undersea landslides, land sliding into the ocean, volcanic eruptions or even asteroid impacts. • Move at speeds of a jet aircraft (500mph or more). • At the shores a tsunami slows down. • It moves at about 70km/hour at the shores.
How tsunamis form • Tsunami are formed as a result of earthquakes, volcanic eruptions, or landslides that can occur under the sea. • The events that occur under the water are huge amounts of energy released as a result of quick upward bottom movement. • For example if a volcanic eruption occurs, the ocean floor may very quickly move upward several hundred feet. • When this occurs, huge volumes of ocean water are pushed upward and a wave is formed. • The Pacific Ocean is especially prone to tsunamis as a result of the large amount of undersea geological activity.
How are Droughts Caused • Droughts are caused when global wind patterns allow high pressure systems to affect an area for weeks, months, or years! • High pressure causes the air around the area to sink, which in terms prevents moisture from rising and creating clouds. • Humans can influence droughts by, over gazing, poor treatment of soil, poor crop selection, clearing the forest, and mining.
Where Droughts Occur and When • Droughts can occur in the hot dry areas. Basically anywhere without water. • Popular spots are Africa, Brazil, India, and the Philippines. • Droughts can occur at any time of the year, as for it can rain anytime of the year.
What are Floods • An over flowing of a large amount of water beyond it’s normal confines. • Flooding can arise from: • Over flowing rivers • Heavy rainfall over a short duration • Unusual inflow of sea water onto land. Ocean flooding can be caused by storms such as hurricanes, high tides, seismic events or large land slides.
How do Floods Occur…Flash Floods • When heavy thunderstorms occur in dry places like the southwest United State, or any desert area. • Due to the dry ground and the water not being able to absorb the water efficiently. • Occur when rain falls closer to the source of a river or stream, and the water than flows downhill quickly.
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