Greenhouse Gases/Effect

Greenhouse Gases (GHG's) are the gases are the various gases that block outgoing long-wave infrared from easily leaving our atmosphere. The Greenhouse Effect (GHE) is the physical mechanism of this blocking mechanism in our atmosphere that determine to a variant degree, how much heat we retain in within the atmosphere.

Greenhouse Gases - CO2, H20, CH4, N2O

Simply put, without greenhouse gases, or the greenhouse effect, the earth would be a frozen planet. Incapable of sustaining life as we know it. There would be no plants, no trees, no animals, just frozen ice and stone.

We need greenhouse gases to capture and hold heat from the sun. Not enough greenhouse gases and we are in an ice age. Too much greenhouse gases and we are in the age of the dinosaurs, or worse. Greenhouse gases are essential to warm to sustain life as we now know it.

The dominant natural greenhouse gases are H20 (water), CO2 (carbon dioxide), CH4 (methane), and Nitrous oxide (N2O). There are also industrial CFC's (Chlorofluorocarbons).

Chiefly, these gases and the ones that keep us warm enough to live relatively comfortably here on earth. The natural forces imposed on our climate system; such as the external forcing of the sun and the Milankovitch cycles, and the internal (terrestrial) climate forcings generally regulate the amount of warmth we enjoy.

The main concern today is that through industrial processes, mankind has altered the natural balance of greenhouse gases and aerosols in the atmosphere and that has altered the climate forcing.

Understanding what it means to add greenhouse gases:

If you need to go somewhere in your car, you need to add gas. Your measure of distance is MPG (Miles per Gallon) or KPL (Kilometers per Liter). The same applies to temperature in our atmosphere. The atmosphere is the tank. The more gas you add, the more distance you can travel. The difference is that in this case the distance is temperature, not miles.

http://www.ossfoundation.us/projects/environment/global-warming/what-we-dont-know

Greenhouse Gas Emissions:

http://www.epa.gov/climatechange/emissions/index.html

The Greenhouse Effect (GHE)

The greenhouse effect is the process, or mechanism, by which greenhouse gases interfere with the direct radiation of heat energy leaving the surface of the planet. In other words GHG's can get in the way of heat escaping, and thus prevent some of the heat from escaping quickly, or easily. When heat energy hits a greenhouse gas molecule it can re-radiate in any number of directions. Some energy radiates back down and some at angles to interact with other molecules.

Eventually, heat energy makes it back out to space. The amount of greenhouse gases in the atmosphere combined with other factors determine the radiative balance, and/or temperature at which relative thermal equilibrium for a planet occurs based on these factors.

How do we know CO2 is a greenhouse gas?

CO2 absorbs infrared heat

What are the major contributors to the greenhouse effect?

Estimating precisely what the contributions are to the effect is complicated by many factors. Spectral overlap, altitude, changing coverage that must be calculated based on averages. However, while getting precise numbers is difficult approximate numbers are beginning to come into focus in a more reliable way.

Gavin Schmidt et al. and Andy Lacis et al., have both had papers published this year that seem to have corralled the effects into general areas with reasonable attribution. Here is what it generally breaks down to: