Trace gas causes its strong absorption of infrared radiation. Below is a table of some of the major greenhouse gases with man-made sources and their contribution to the enhanced greenhouse effect. Key Greenhouse Gases and Sources In contrast, the most abundant gases in the atmosphere are not greenhouse gases. The main reasons is because they cannot absorb infrared radiation as they do not have vibrations with a dipole moment. For instance, the triple bonds of atmospheric dinitrogen make for a highly symmetric molecule that is very inert in the atmosphere. The residence time of a trace gas depends on the abundance and
Atmosphere may have outer atmospheres with compound molecules. Atmospheric pressure at a particular location is the force per unit area perpendicular to a surface determined by the weight of the vertical column of atmosphere above that location. On Earth, units of air pressure are based on the internationally recognized standard atmosphere (atm), which is defined as 101.325 kPa (760 Torr or 14.696 psi). It is measured with a barometer. Atmospheric pressure decreases with increasing altitude due to the diminishing mass of gas above. The height at which the pressure from an atmosphere declines by a factor of "e" (an irrational number