Catastrophic Events Catastrophic Event An event that results

Catastrophic Events

Catastrophic Event • An event that results from Earth processes and that can cause damage and endanger human life Weather Geologic – tornado – hurricane – floods – drought – wildfire earthquake tsunamis volcanoes

Catastrophic Event • The result of – Processes in the atmosphere – Processes on the Earth’s surface – Processes in the oceans – Processes inside the Earth

Catastrophic Events • Can effect Earth in several ways • Surface – speed up erosion and deposition • Inside Earth – change the ground

Human Activities • Where people decide to live can increase the damaging effects of natural hazards • How people use land can also alter Earth’s systems in ways that contribute to catastrophic events

Impact of How People Use Land • People can alter the land so that flooding and fire can be worse – New Orleans built in a low depression – Queensland built on fire prone plains – California builds on steep slopes and creates mudslides

Tornado

Tornado A violently rotating column of air formed when warm and cold air meet.

Tornado • Cause – cold and warm air colliding when thunderstorms meet • Impact to Earth – kills plants, damages topsoil • Impact to People – high winds destroy buildings, can have flooding • Similar to – hurricane • How are they similar – high winds and rain

Statistics Texas ranks 11 th among the 50 states in density of tornadoes with an average of 5. 7 tornadoes per 10, 000 square miles, per year.

Hurricane

New Orleans after Katrina

hurricane A large rotating spiral of air formed when high and low pressure systems meet over warm ocean water.

Hurricane • Cause – air pressure differences over the ocean • Impact to Earth – kills plants, destroys beaches • Impact to People – high winds destroy buildings, can have flooding • Similar to – tornado • How are they similar – high winds and rain

Tsunami

tsunami A large, fast moving wave caused by an earthquake deep under the ocean floor.

Tsunami • Cause – earthquake under the ocean floor • Impact to Earth – destroys beaches and coral reefs • Impact to People – large loss of life, destroys buildings • Similar to – earthquake, flood, volcano • How are they similar – causes tsunami, water, pressure release

Volcano

volcano A vent in the Earth’s surface which allows magma and ash to escape. It relieves pressure.

Volcano • Cause – build up of pressure deep inside Earth • Impact to Earth – burns plants, creates new land • Impact to People – burns or covers buildings • Similar to – earthquake, wildfire • How are they similar – pressure release, burns everything

Earthquake

Earthquake

earthquake A vibration of the Earth’s surface caused by a release of pressure deep within the Earth. Tectonic plate movement.

Earthquake • Cause – moving tectonic plates • Impact to Earth – changes the look of the land • Impact to People – damages buildings, kills people • Similar to – volcano, tsunami • How are they similar – pressure release

1847 -2012

Drought

drought Extremely dry conditions caused by a lack of rain over a long period of time.

Drought • Cause – lack of rain, heat • Impact to Earth – kills plants and animals • Impact to People – money loss from crop and livestock damage • Similar to – wildfire • How are they similar – loss of life and vegetation

Statistics

Wild Fire

Wildfire

wildfire A large are of fire caused by a lightning strike or man.

Wildfire • Cause – lightning, can be man-made • Impact to Earth – burns everything, fertilizes the soil • Impact to People – destroys everything in it’s way • Similar to – drought, volcano • How are they similar – loss of life, fire

Flood

flood Large amounts of water caused by heavy rains or melting snow.

Flood • Cause – too much rain • Impact to Earth – changes the land, fertilizes the soil • Impact to People – loss of life and buildings • Similar to – tsunami • How are they similar – large amounts of water

• Which of these natural disasters can happen in our area?