High-Resolution Infrared Laboratory Spectroscopy to Support Atmospheric Measurements
Electromagnetic radiation includes not only visible light, but infrared radiation, microwaves, radio waves, ultraviolet light, and X-rays. Because this radiation takes the form of waves, scientists and engineers use the characteristics of wavelength or frequency to distinguish the various types of radiation. The highest-energy radiation has the highest frequency and the shortest wavelength. A spectrum shows the intensity of radiation received by a detector at each wavelength or frequency. The spectrum can be shown as an image on a photographic plate or as a graph of intensity vs.frequency. The features of the spectrum depend on the characteristics of the light source and on the nature of the matter between the source and the detector.
A spectrum shows the intensity of radiation received by a detector at each wavelength or frequency. The spectrum can be shown as an image on a photographic plate or as a graph of intensity vs. frequency. The features of the spectrum depend on the characteristics of the light source and on the nature of the matter between the source and the detector.
Molecules in the gas phase absorb and emit radiation mainly at frequencies from the microwave to the visible. Each molecule has a unique spectrum which is determined by the types and arrangement of atoms in the molecule.And since molecules are merely building blocks for substances,the spectrum of a molecule can identify the type of substance to which it belongs.
A spectrum of the atmosphere can be recorded by an instrument on the ground or an instrument carried by a satellite, balloon, or aircraft. Atmospheric scientists can study the spectrum to determine the types and amounts of molecules present in the atmosphere at the time and place the spectrum was recorded. This is a difficult task, very much like examining the fingerprints on a cookie jar to find out who has taken the cookies. It is important to have laboratory measurements of the spectrum of each molecule to compare to the spectrum of the atmosphere, which is a mixture of many molecules. With these measurements as a guide, determinations can be made concerning the makeup of the atmosphere.
Atmospheric Trace Molecule Spectroscopy (ATMOS)
High-Resolution Infrared Laboratory Spectroscopy to Support Atmospheric Measurements
 Atmospheric Sciences |