Chapter 1 - Lesson 2 Streams and Rivers, Lakes

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Chapter 1 - Lesson 2 Streams and Rivers, Lakes

• Chapter 1
• The Earths Bodies of Water

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Streams and Rivers page 26

• Water covers more than 70 of the Earth
• Water is in the ground and in the air we breathe
• People, Plants, and Animals all need water to
  live

Weathering - is the process of breaking up rocks
into smaller pieces called sediment
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Streams and Rivers

• Streams are bodies of water that flow over land
  in a channel
• Most streams begin on high ground, among hills or
  mountains
• The sources of a stream usually consist of
  melting snow/ice or an overflowing lake
• At the end of a stream is the mouth which empties
  into another body of water

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Streams and Rivers

• Streams can be as small as a shallow brook
• Or as large as a river, the largest and most
  important streams
• Most rivers form from many smaller streams coming
  together, these are called tributaries

Tributaries are streams or rivers that flow
into a larger stream or river
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Streams and Rivers

• The more tributaries that empty into a river the
  larger the river grows
• Together the river and its tributaries are called
  a river system

River System a river and all of its tributaries
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Streams and Rivers

• Each continent, except Antarctica, has major
  rivers and river systems.
• Africa has the Nile, Asia has the Yangtze,
  Australia has the Murray, Europe has the Danube,
  North America has the Mississippi, and South
  America has the Amazon

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Streams and Rivers, Lakes

• The Nile is the Earths longest river, it flows
  from Central Africa to the Mediterranean Sea
• The Amazon is the Earths largest river, carrying
  more water than the Mississippi, Nile and Yangtze
  combined
• River Systems carry or drain water away from the
  land around them (drainage basin)
• Rivers are important for many reasons including
  drinking, cleaning, travel and trade

Drainage Basin Land drained by a river system
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Streams and Rivers
Drainage Basin
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• Why did many of the worlds first settlements
  form along rivers?
• (pg.27)

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Lakes

• Lakes are bodies of water surrounded by land
• The word lake comes from the Greek language
  meaning hole because most lakes are holes in the
  Earth that fill with water
• Lakes exist on every continent except Antartica
• The greatest amount of lakes exist where there
  was once many glaciers such as North America and
  northern Europe

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Lakes

• During the last Ice Age, glaciers gouged huge
  holes in the Earth and the holes filled with the
  water from the melted glaciers
• Lakes also form where rainwater collects in huge
  holes made in other ways
• Crater Lake in Oregon was formed in a crater of
  an extinct volcano

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Lakes

• Lake Baikal in Russia is the deepest lake on
  Earth measuring 5,315 feet deep it was formed in
  a huge crack in the Earths crust called a rift

Rift a long and deep crack in the Earth
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Lakes

• North America has the most lakes out of all of
  the continents
• The largest of the North American lakes are the
  Great Lakes
• One fifth of all of the fresh water on the
  Earths surface is found in the Great Lakes

H Huron O Ontario M Michigan E Erie S
Superior
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Lakes

• There are some large bodies of water called seas
  that are actually lakes
• The difference is that they are not fresh water,
  but salt water and that is why they are called
  seas instead of lakes
• The Dead Sea, Sea of Galilee, and the Caspian Sea
  are lakes
• The lowest lying lake is the Dead Sea between
  Israel and Jordan
• The highest lake is Lake Titicaca in South America

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Lakes
The Dead Sea
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Lakes
Lake Titicaca
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Lakes

• Not all lakes are made by nature
• Some are man-made and are called resevoirs
• People build dams to control river flooding or to
  generate electricity

Reservoir a lake that forms behind a human made
dam
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Terms to Know

• Reservoir
• Rift
• Drainage basin
• River system
• Tributaries
• How did Ice Age glaciers form lakes in North
  America and Europe? (pg. 28)