7th Grade
Unit 8:
Natural Events that Change
the Environment
Lesson 1:
Impact of Catastrophic
Events on the Earth
Vocabulary of Instruction:
1. Catastrophic Event
•
•
Are sudden,
natural or manmade situations
where change
and destruction
may occur without
prior knowledge
or preparation.
Ex:
–
Supervolcano
2. Drought
• Long periods of usually low precipitation (rainfall).
3. Earthquake
• The shaking and
trembling that
result from the
sudden movement
of the earth’s crust
(Rock beneath
Earth’s surface).
San Andreas Fault, California
4. Equilibrium
• A state at which
opposing forces
in a system are
equally
balanced or
stable.
5. Flood
• Is when a body of water suddenly increases
in volume, sending water over its banks into
nearby land that is normally dry.
6. Hurricane
• A powerful tropical storm with heavy rains and
winds with speeds of 119 kilometers per
hour (74 miles) or higher. The winds rotate
around an area of calm known as the eye.
7. Natural Disaster
• Any sudden event that results from Earth
processes and that can cause damage or
endanger human life.
8. Tornado
• A rapidly whirling, funnel-shaped cloud that
sometimes develops during a violent
thunderstorm and reaches down from a storm
cloud to touch the Earth’s surface.
9. Tsunami
• Is a very large sea wave, or series of
waves, produced by underwater earth
quake or volcanic eruption.
10. Volcano
• An opening in the earth's crust through
which molten lava, ash, and hot gases are
ejected during the eruption.
11. Wildfires
• A raging, rapidly spreading fire.