Key Idea: The transfer of thermal energy from one place to another by the movement of air in the atmosphere and water in the oceans increases the air temperature at some places and decreases the air temperature at other places.

Students are expected to know that:

  1. As air and ocean currents move around the earth they influence the air temperature of the places along their path by transferring thermal energy to and from the air as they move. Air and ocean currents can have a lot of thermal energy and, therefore, increase air temperature where they move, and currents can have little thermal energy and, therefore, decrease air temperature where they move.
  2. Because the air at the equator tends to be warmer than the air in surrounding regions, air at the equator tends to rise high into the atmosphere and move toward the north and south. As the air rises upward at the equator, colder air moves along the surface of the earth and replaces the rising warmer air at the equator. Because the air at the poles tends to be colder than the air in surrounding regions, air tends to sink toward the surface of the earth and move toward the equator.
  3. Water also moves around the surface of the earth, and it generally moves along the same path that brings cold water from the poles toward the equator and warm water toward the poles.
  4. The movement of warm air and water away from the equator and of cold air and water away from the poles results in the transport of thermal energy around the surface of the earth.

Boundaries:

  1. Students are not expected to know about circulation patterns of air around the earth away from the equator and poles.
  2. Students are not expected to know about the circulation
  3. Students are not expected to know factors aside from temperature that cause currents to form, such as the humidity of air and the salinity of water.
  4. Students are not expected to know what factors influence the directions that fluids move around the surface of the Earth as part of this idea, such as the Coriolis Effect.
  5. Students are not expected to know why the ocean circulates according to the pattern described, and they are not expected to be able to describe the path of ocean circulation.
  6. Students are not expected to know that the path of ocean circulation has changed in the past.
Frequency of selecting a misconception

Misconception
ID Number

Student Misconception

Grades
6–8

Grades
9–12

CLM044

Thermal energy cannot be transferred between air and water (AAAS Project 2061, n.d.).

25%

21%

CLM037

When air moves, its thermal energy moves separately from the moving air (AAAS Project 2061, n.d.).

16%

11%

CLM034

When water is moving, its thermal energy moves separately from the water (AAAS Project 2061, n.d.).

16%

11%

Frequency of selecting a misconception was calculated by dividing the total number of times a misconception was chosen by the number of times it could have been chosen, averaged over the number of students answering the questions within this particular idea.