Module 3 Review

Using the module learning objectives, here is a short review of the material in this module:

1. Radiation
   • All matter emits and absorbs light. Atoms and molecules emit light due to transitions between specific energy levels, resulting in sharp, well-defined "lines" of radiation. An emission line is the wavelength at which a specific atom or molecule emits light.
   • Solid bodies have so many different lines, and so many different energy levels due to internal vibration, that they emit a broad spectrum of light at all wavelegnths, which is strongest at one central wavelength. This is called blackbody radiation, an example of which is a glowing stove burner. As the object gets hotter, the emission gets brighter and moves towards the ultraviolet.
   • In the atmosphere, it is important to remember that the Earth absorbs at all wavelengths, including the UV light primarily emitted by the Sun. Atmospheric ozone blocks UV light. THe Earth emits infrared light. Greenhouse gases absorb infrared light.
2. Atmospheric Transport occurs by the following methods
   • Convection
   • Conduction
   • Advection
   • Dispersion
   • Pressure Gradient Forces
   • Coriolis Forces
3. Energy Balance
   • The Sun emits UV light, which is absorbed by the Earth. The Earth emits an equal energy of infrared light. Energy cannot be created or destroyed.
   • If greenhouse gases trap the infrared light the Earth is emitting, the Earth will warm up until the amount of light energy that escapes the atmosphere is once again equal to the amount of light energy that enters the atmosphere.

Module Self-Assessment Test