Energy in Earth’s Atmosphere Section 16.1 Section 16.2

Energy From the Sun Almost all of Earth’s energy radiates from the sun in the form of electromagnetic waves Electromagnetic waves - can move through empty space - classified by wavelength

Energy in the Atmosphere The amount of energy that reaches the surface is affected by the atmosphere Some sunlight is absorbed or reflected by the atmosphere before reaching the surface

Energy at Earth’s Surface When Earth’s surface is heated, it radiates most of the energy back into the atmosphere as infrared radiation. Not all the heat escapes back into space

Thermal Energy and Temperature Temperature – the average amount of motion of each particle of a substance

Thermal Energy and Temperature Thermal energy – The total energy of motion in the particles of a substance Teapot and cup of tea have the same temperature. The teapot has more thermal energy because it has more particles.

Measuring Temperature Air temperature is usually measured with a thermometer. Contains a liquid (mercury or colored alcohol) that expands up the tube when heated.

Temperature Scales

Temperature Scales Converting temperature scales oC = 5/9 (oF – 32) oF = 9/5(oC)+32

Heat Transfer Radiation – transfer of heat by electromagnetic waves Conduction – transfer of heat by direct contact Convection – transfer of heat by fluid movement and differences in density

Heat Transfer The troposphere uses all three methods of heat transfer