Chapter 16 Test Review

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Chapter 16 Test Review

• Place these notes in your Meteorology Notebook.

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• Strong steady winds blowing over dry topsoil are
  conditions most likely to cause a dust storm.
  Video
• A strong wind can carry clay and silt in the
  atmosphere over very long distances, even over
  oceans.
• Deep hollows known as blowouts tend to form in
  areas where the climate is dry and vegetation is
  patchy.
• Sands are more abrasive than silts and clays
  because sand grains tend to be larger and harder.

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• The shape of a ventifact gives information about
  the direction of prevailing winds.
• Loess particles are small enough to be moved and
  deposited by the wind.

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• Where winds blow steadily from the west, the
  steepest slope of a sand dune will be on the east
  side.
• The following can affect the shape of a sand
  dune
• The steadiness of the wind
• The supply of sand
• The amount of vegetation present

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• Types of Sand Dunes

http//www.geog.ucl.ac.uk/hmomiji/images/types2.j
pg
7
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barchan.jpg
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http//www.geog.ucl.ac.uk/hmomiji/images/DFS.gif
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http//www.geog.ucl.ac.uk/hmomiji/images/nssimc.j
pg
10
http//www.physicalgeography.net/fundamentals/10ah
.html
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• Most water waves are caused by winds.
• The highest lake waves cannot be as big as the
  highest ocean waves because lakes have shorter
  fetch.
• The period of a wave is the time it takes for one
  wavelength to pass a given point.
• A particular wave has a wavelength of 30 meters
  and a period of 5 seconds. What is its speed?
• 30 meters
• 5 seconds

6 meters per second
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• As waves pass, an object floating in deep water
  will bob up and down as the wave passes.
• Wave refraction occurs when the section of a wave
  in shallower water slows down.
• Headlands wear away more quickly than bay
  shorelines because wave energy is concentrated on
  headlands.
• In shallow water a wave breaks when its lower
  part slows down, causing its upper part to move
  ahead.

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• Beach drift is the movement of sand down a beach
  in a zigzag pattern.
• Strong, dangerous surface currents that can carry
  swimmers out from shore are rip currents.
• Beach sand on a coral island is likely to consist
  primarily of calcite fragments.
• Most irregular shorelines appear to have formed
  when coastal areas were flooded by the sea.

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• The diagram shows a shoreline where approaching
  waves are refracted, or bent, until they approach
  the shore more head-on. Shade the area where
  erosion is likely to be occurring fastest. Circle
  the area where sand is most likely to be
  deposited to form a beach. Draw an arrow showing
  the direction of the longshore current between
  points A and B. (4 points)

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Shade the area where erosion is likely to be
occurring fastest.
Circle the area where sand is most likely to be
deposited to form a beach.
Draw an arrow showing the direction of the
longshore current between points A and B. (4
points)
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• Essay 1
• Describe how individual sand particles move as an
  entire sand dune migrates. What can prevent a
  dune from migrating?
• As wind blows against the windward side of a
  migrating sand dune, individual sand particles
  are carried over the top. Over time this allows
  the particles to fall onto the leeward side
  moving the entire dune leeward. A dune may not
  migrate if the wind does not blow consistently in
  a particular direction. Vegetation can also hold
  a dune in place.

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• Essay 2
• Compare a beach made of sand with one made of
  pebbles. What factors may account for the
  difference in the makeup of the beaches?
• Over time, sand and clay on a beach are washed
  away by ocean waves. A sandy beach generally
  occurs where the sea floor has a gentle slope,
  and a constant supply of sand is delivered by
  rivers. A pebble beach generally occurs where the
  sea floor is steeper, and both sand and clay are
  washed away.