Catastrophic Events Notes

Catastrophic Event/Natural Hazard An event that results from Earth processes and that can cause damage and endanger human life Examples: hurricanes, tornados, floods, earthquakes, volcanoes, tsunamis, wildfires, etc.

Hurricane Wind speed >74 mph Huge, many miles across Often accompanied by torrential rains Storm surge, large waves, and flooding Wind damage Occur June-November

Hurricanes cause… Storm surge and tidal flooding--Storm surge is the rising wall of salt water that comes ashore with a land falling hurricane, and is responsible for 90 percent of all hurricane related deaths. Landfall = time/place when the eye wall of a hurricane hits land

Cause cont… Heavy rain and flooding--After hurricanes make landfall, and their winds slow down, the amount of rainfall becomes a major factor, and can cause significant flooding.

Cause cont… High Winds-- it determines how powerful the storm is, and how much storm surge and damage it can cause (can reach up to 200 mph).

Beach Erosion… moves weathered rocks and soil from one place to another it can move slowly or quickly A car is submerged in sand after Hurricane Ike came through the area, September 17, 2008 in Gilchrist, Texas.

After 5 years, what do you think will happen to the beach and the house? The land wears away due to beach erosion

Part 2 IEF Notes

What is this a picture of?

Tornado Definition: A funnel-shaped column of rotating air (wind) that stretches from the bottom of clouds to the ground Wind speed 100-250 mph ~250 ft across (average) Occur during thunderstorms Wind damage Spring/Summer Mostly in Midwest (Tornado Alley)

Tornadoes cause… Destruction to buildings, bridges and anything in the tornadoes path death hail damage wind damage (can reach 140 mph)

Tornados and Hurricanes Differences: Tornados Hurricanes <1 mile across >50 miles across Form over land Form over water Spring/Summer Summer/Fall Little rainfall Lots of rainfall/flooding Little/no warning Forecasted

Flood An overflow of water that submerges (covers) land not normally covered by water Caused by heavy rains (hurricanes, thunderstorms) Storm surge (hurricanes) Plants/animals/humans drown Destroys buildings Erodes land

Earthquake Movement of tectonic plates (rock) along a fault line (crack in the earth) Forms mountains Destroys buildings Often causes fires due to broken gas lines under cities

Volcano An opening in the Earth's crust that allows magma/lava (melted rock) to come out Burns vegetation Releases ash into the air Kills animals Forms new mountains/islands

Effects of Catastrophic Events/Natural Disasters Beach/land erosion Destroy habitats Kill living things (plants, animals, humans

Exit Activity Create a Venn Diagram that compares and contrasts two natural catastrophic events- Hurricanes and Tornadoes