EQ: What effect do the Earth and the Sun have on our weather?

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EQ What effect do the Earth and the Sun have on
our weather?
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• The Sun is a star at the center of our solar
  system. It is mostly made of hydrogen and helium
  gas. It is a nuclear energy furnace giving off
  light and heat.

1,300,000 Earths would fit inside the Sun. The
Sun is 150,000,000 kilometers from the Earth, or
11,600 Earths lined up side-by-side.
http//chandra.harvard.edu/resources/illustrations
/solarsystem.html
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Solar Energy Reaching the Earth
earthobservatory.nasa.gov
This diagram shows what happens to the suns
light and heat when it reaches Earth. Notice
that about 50 of the energy is absorbed by the
Earths surface, thus heating land and oceans.
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Heating of Earths surface is greatest at the
Equator and less toward the Poles. The surface
heats the atmosphere.
SUN
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• Lets see what happens to the unequal heating of
  the Earths atmosphere. Lets pretend that the
  Earth did not rotate on its axis. Heated air at
  the Equator would tend to rise because it is less
  dense. Cold air at the Poles is heavier and it
  sinks.

The sinking cold air flows south to replace the
rising hot air, and a convection cell is formed.
The moving air is wind. The surface winds in the
northern hemisphere would be from the north and
the opposite to the south.
North Pole
COLD
HOT
Equator
South Pole
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• But the Earth does rotate on
• its axis. It turns from West
• to East at about 1000 miles
• per hour at the Equator! It breaks the convection
  cells
• into smaller ones and makes the winds appears to
  curve to the right in the northern hemisphere and
  to the left in the south. This motion is called
  the Coriolis Effect. See how it works to the
• right. A marble is placed at the center of a
  rotating disk and released.

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• The result of unequal heating of the Earth and
  the Coriolis Effect create the global wind
  pattern shown below.

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• Air that stays over one area for a long time
  takes on the temperature and moisture content of
  that area. The air is now called an air mass. In
  the summer, warm air masses can grow and move
  north. In the winter, cold air masse can grow
  and move south.

Symbols A Arctic (very cold) P Polar
(cold) T Tropical (warm) c Continental
(dry) M Maritime (humid)