Weather

Temperature Controls May 6, 2008

Temperature

• Temperature is the measure of the average kinetic energy of the particles of an object.

• Think of a thermometer as a speedometer!

• A temperature control is any factor that causes temperature to vary from place to place and from time to time.

• What do you think are some temperature controls?

Temperature Controls

• Factors that exert a strong influence on temperature include latitude, heating of land and water, altitude, geographic position, cloud cover, and ocean currents.

Latitude

• Because the axis remains pointed toward the North Star as Earth moves around the sun, the position of Earth’s axis to the suns rays is constantly changing.

• Flashlight Demonstration

Heating of Land and Water

• Land heats more rapidly and to higher temperatures than water. Land also cools more rapidly and to lower temperatures than water.

• How can this difference affect the temperature? (Remember the heat source for the troposphere!)

Compare Using a Graph

• What does the left axis indicate?

• What does the right axis indicate?

• What does the bottom axis indicate?

• What do the curves indicate about the climates of each city?

Geographic Position

• The geographic position can greatly influence temperatures experienced at a specific location.

• Windward vs. Leeward • Mountain barriers

Altitude

• These two cities have different altitudes.

• Which one has a higher altitude?

• What is the relationship between altitude and temperature?

Cloud Cover and Albedo

• Albedo is the fraction of total radiation that is reflected by any surface.

• Many clouds have a high albedo, and therefore reflect a significant portion of the sunlight that strikes them back to space.

• At night, clouds have the opposite effect, and reflect outgoing radiation emitted by Earth back to Earth.

Cloud Cover and Albedo Illustrated

Isotherms

• Isotherms are lines that connect points that have the same temperature.

Assignment

• Read pg. 488-493 • Complete 17.3 ws