Catastrophic Events Catastrophic Events Catastrophic Event Any event

Catastrophic Events

Catastrophic Events § Catastrophic Event – Any event naturally occuring or caused by human action that: § Causes severe damage to the land § Endangers human life or causes loss of life § Speeds up the effects of erosion and deposition – Also known as natural disasters

Tornadoes High speed rotating winds often greater than 250 mph forming a funnel shaped cloud • Extreme low pressure causing materials to be sucked up into the funnel like a vacuum • Ranked from F-0 Tornado (light damage such as broken tree limbs) to F-5 Tornado (total demolition of and area including concrete sucked up from the ground) • Causes erosion •

Droughts Long periods of time with little to no significant precipitation What other disasters can this cause? Famine, Dust Storm, Erosion of soil.

Wildfires • Caused by lighting or careless handling of fire • What conditions could make fire more likely to occur? • Lighting, drought, high winds • What other disasters could this bring? • Floods, Erosion, smoke blocking out sunlight

Floods § Occurs when a body of water overflows its normal boundaries § What disasters could cause a flood? § Caused by heavy rains from hurricanes or thunderstorms § melting snow or ice § Causes damage to home, property and erosion of top soils

Hurricanes/Typhoons/Cyclones §Called a hurricane in the Atlantic Ocean, a typhoon in the Pacific Ocean and a cyclone in the Indian Ocean What other disasters can this cause? §A large, swirling, low pressure system forming over a warm ocean with a calm Often bring storm surge (flooding), tornadoes “eye” in the center and heavy rain onto land causing erosion. The more people move towards the coasts the greater in damage costs

Earthquakes occur when the plates, making up the crust of the Earth, move causing energy to be released in the form of a wave The movement is along the boundary of the plates called a fault and the waves are called seismic waves Seismic waves are measured by the Richter Scale on a machine called a seismograph

Tsunamis After an earthquake occurs on the ocean floor, the shift can cause a huge wave to form and rush towards land Most tsunamis are less than 1 meter deep on formation however as the distance from the seafloor to the surface of the water decreases as the wave moves towards land, the height of the tsunami increases (can be as high as 30 m above sea level) racing towards land at speeds averaging 700 meters per hour. Not all ocean floor earthquakes form a tsunami, however, a tsunami cannot form without the earthquake occurring

Volcano §Magma from deep within the Earth rises to the surface of a cone shaped mountain scorching everything in its path §Volcanoes form where there is movement of the plates of the Earth’s crust (both at convergent and divergent boundaries)

Volcanic Eruptions § How can a Volcanic Eruption cause problems away from the immediate area? § Volcanic dust and ash are thrown into the air blocking sunlight for long periods. § How would this affect climate? § Colder temperatures and fewer plants § Higher amounts of sulfur producing ACID RAIN. § Potential for flooding, mudslides erosion.

Ring Of Fire § Area along the Pacific Plate boundaries where volcanic eruptions and earthquakes occur.

9. Mass movements Large areas of land changes location over a period of time (change can be gradual or can occur quickly) What are different types of mass movement? Avalanche Landslides Mudflows Usually occurs with another event such as: floods, earthquakes, volcanic eruptions or after wildfires

Summary Questions § Scientists hypothesize that a large meteorite struck the Earth and killed all the dinosaurs, even those on the other side of the Earth. Describe how this event could have caused their extinction. § How do we plan ahead in order to survive catastrophic events?

Yet more Summary Questions § Explain possible impacts of a volcanic eruption on the Earth’s surface. § If cities along coasts and major inland waterways experienced a population growth, what affects would this growth cause if floods and hurricanes occur.