THE SURFACE OF EARTH CHANGES

MST Lesson PlanGrade 4 Unit Plan

Diana Walcott-WardShantell King Susan CharlesSpring 2013

Erosion The process by which water, ice, wind or

gravity moves fragments of rock and soil.

There are many types of erosion

Water erosion Wind erosion Ice erosion

Each one can do significant damage to the land.

Match the cause to the effect

Ice erosion

Wind erosion

Water erosion

Creation of U-Shaped Valleys

Rivers, streams, and run off

Loss of soil on the ground

Can you guess which pictures were caused by wind, water, or ice erosion?

Weathering • The breakdown do the materials of Earth’s

crust into smaller pieces. There are two types of weathering:

Physical weathering and chemical weathering

Physical weathering• Process by which rocks are broken down into

smaller pieces by external conditions.• Types of Physical weathering

– Frost heaving and Frost wedging– Plant roots– Friction and impact– Burrowing of animals– Temperature changes

Chemical Weathering• The process that breaks down rock through

chemical changes.• The agents of chemical weathering

– Water– Oxygen– Carbon dioxide– Living organisms– Acid rain

Can you spot 2 physical and chemical agents?

Natural Disasters Natural disasters such as flood, fire,

earthquake, tornado and windstorm affect thousands of people every year. We will discuss the following:

Hurricanes Earthquakes Tornadoes Volcanoes

Earthquakes An earthquake is the sudden, rapid

shaking of the earth, caused by the breaking and shifting of never-ending rock underground as it releases strain that has accumulated over a long time.

Unlike other natural disasters earthquakes occur with virtually no warning. There is no advance warning or immediate preparation with earthquakes.

Hurricanes A type of tropical cyclone or severe

tropical storm that forms in the southern Atlantic Ocean, Caribbean Sea, Gulf of Mexico, and in the eastern Pacific Ocean.

Unlike earthquakes, hurricanes are predicted days to weeks in advance, giving communities time to prepare.

Tornadoes Tornadoes are nature’s most violent

storms. A tornado appears as a rotating, funnel-shaped cloud that extends from a thunderstorm to the ground with whirling winds that can reach 300 miles per hour.

Like earthquakes, tornadoes can bring mass destruction in a matter of minutes, and individuals typically have little time to prepare.

Volcanoes A volcano is a mountain that opens

downward to a reservoir of molten rock below the surface of the earth.

When the opening of top of the volcano belch out smoke, gases, ashes, and lava comes out volcanoes erupt.

Natural Disasters Write two sentences about the natural

disasters below.

Video about Earth’s Changes

http://www.youtube.com/watch?v=H2h6uXlL8gI

A natural disaster in my area

What might you see, hear, or smell after a hurricane came through this area?

Natural Disaster Safety Which items belong in your natural

disaster kit?