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SELF QUIZ 7: CLIMATE 2
Questions | Answers
 

1. Four major causes of deserts.

  • 1) Descending air in the Hadley Cells
  • 2) Rainshadow Effect
  • 3) Cold ocean offshore.
  • 4) Being far away from a source of water

2.

Earth showing latitudes, convection cells, and prevailing winds

3. 30 degrees north and 30 degrees south latitudes. The air in the Hadley Cells descends, the air heats, the relative humidity decreases, and this decreases the chance of precipitation and a desert forms.

4. Deserts most commonly form on the west coast of continents in the northern hemisphere because ocean currents are circulating clockwise, bringing cold water from the arctic southward along the west coast of the continent. Deserts most commonly form on the west coast of continents in the southern hemisphere because ocean currents are circulating counterclockwise, bringing cold water from the antarctic northward along the west coast of the continent. The cold ocean cools the air above it. As the cooled air from above the ocean moves over the land warmed from the sun, the air temperature rises, the relative humidity decreases, and the chance of rain decreases..

5. The Rainshadow Effect occurs on the downwind side of mountain ranges because as the air is blown over the top of the mountain and descends, it heats, the relative humidity decreases, and the chance of rain decreases.

6. The seasons are caused by the 23.5 degree tilt of the Earth and the Earth's revolution around the sun. As the Earth revolves around the sun, the angle each hemisphere is pointing toward or away from the sun changes. When the northern hemisphere is pointed most perpendicularly to the sun (June 21st), it is summer in the northern hemisphere. But this is when it is winter in the southern hemisphere because June 21 is when the southern hemisphere is pointed most away from the sun so the sun's rays are spread over the most ground and the sun's rays have to travel through the most atmosphere.

7. It is cooler during the winter because the northern hemisphere is tilted away from the sun and so the sun's rays must pass through more atmosphere (which reflects and absorbs the sun's energy) and because the sun's energy is spread over a larger area due to the sun's rays coming in at a low angle (less perpendicular). It is warmer during the summer because this is when the northern hemisphere is tilted toward the sun and the sun's rays are most perpendicular so are most concentrated and travel through the least amount of atmosphere (thus are reflected and absorbed less so that more reaches the ground).

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