Most people have probably heard of their “Carbon Footprint” and can even tell you that it has to do with how much Carbon Dioxide they are responsible for producing. Most people do not realize that water vapor is the most abundant greenhouse gas mostly because the water vapor isn’t considered to be a big deal in terms of contributions to "the problem." Water vapor actually helps to absorb radiation to keep the Earth warm. CO2 is the gas that contributes the most by volume of the greenhouse gases, but it is not the strongest component. Methane (CH4) and Nitrous Oxide(N20) are two other main gases that compose the greenhouse gases. Man-made industrial gases also are contributors such as Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs), and Sulfur hexafluoride (SF6). There are hundreds of gases that exist in very small portions but will not be discussed at this time.
When sunlight enters Earth’s atmosphere it is dispersed and much of the sunlight strikes the surface. Some of this radiation is absorbed and some is reflected back towards space. The greenhouse gases trap this radiation, which would have otherwise escaped, and scatter the energy. This phenomenon is actually what makes the Earth a suitable place for humans to live since the sun’s heat is trapped in the atmosphere and keeps us warm. [16] However, too much of these greenhouse gases can become a bad thing. With the amount of these gases increasing each year, our atmosphere is warming up and the surface temperature is steadily increasing. The following charts show the three major gases and their emissions by sector. [17]
We can conclude that most of the N2O and CH4 comes from agricultural byproducts while agriculture only makes up 12.5 percent of all GHG emissions. CO2, which composes 72 percent of the GHGs, comes mostly from power stations, industrial processes, and then transportation fuels.
