Water Cycle - Atmosphere (4)
Post Lab 

  • Comparing the differences of air temperature.
  • Exploring how wind is created.
  • atmosphere
  • front
  • sea breeze
  • wind
  • worksheet

Students use a worksheet to learn about sea breezes.



Land and water retain heat differently.  Water retains heat much longer than land, although it takes a longer time to heat up.  Land cools and heats up more quickly than water.  Day and night causes a large change on land, but not in water.  The larger a body of water is the longer it takes to heat and cool.  

The Sun beating down on the coastal land heats the land and the air over it more quickly than it heats the ocean and its overlying air.  Circulation is started when a "sea breeze" of cool air sweeps in from the ocean, pushing up the air warmed by the land which then rises (less dense) and streams out  toward the ocean.  Air cooled by the sea sinks and flows landward to fill the area of low pressure created by the warm land, causing onshore breeze.  At night, the land loses its heat more rapidly than the water.  The air above it is chilled, while the ocean air is relatively warm.  The colder air now sweeps from the land to the water, producing the "land breeze."

Winds are also created when warm air rises and cool air falls.  When you hear the terms cold front or warm fronts they are generally talking about a mass of air with the same temperature.  A front is when two masses of air meet.  When 2 different masses of different temperature meet, it creates a different type of weather. 

The San Francisco area in California is famous for its fog.  Many people in the area do not even realize why the fog comes into town.  The story has to do with sea breezes.  East of San Francisco the land gets very hot.  The cold Pacific water is to the west.  As the land heats up, the wind moves the fog quickly into San Francisco.  It is very dramatic because there are coastal mountains that prevent the fog from going through most of the areas, so the fog rolls in through the Golden Gate bridge.  Many people have never seen such a sight

  1. Give students a worksheet and go over each of the diagrams.  You may want them to color the water blue, so it stands out better.  The answer to the question is on the diagram.  Make sure students notice the difference of temperature, which is the driving force behind the sea and land breezes.
  2. You may want students to discuss the difference of living near a coast and living  inland.    

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