What are greenhouse gases?

Greenhouse gases are components of the atmosphere that contribute to the greenhouse effect.¹ Some greenhouse gases such as carbon dioxide occur naturally and are emitted to the atmosphere through natural processes as well as human activities (like industrial production).

Other greenhouse gases like fluorinated gases are created and emitted solely through human activities. In the end, it is always human-based activities that create the majority of emissions for any of the greenhouse gases.

The principal greenhouse gases are:

• Carbon Dioxide (CO₂)
• Methane (CH₄)
• Nitrous Oxide (N₂O)
• Fluorinated Gases

Figure 1:

Source: Inventory of U.S. Greenhouse Gas Emissions and Sinks (2008), EPA.

To learn more about main greenhouse gases click here

¹http://en.wikipedia.org/wiki/Greenhouse_gas