Summary of the Three Major Anthropogenic GHGs

Greenhouse gases (GHGs) contribute to the greenhouse effect by absorbing the sun’s rays (specifically infrared radiation) causing the greenhouse effect, which warms the surface of the Earth. Although greenhouse gases occur naturally in the atmosphere, the elevated levels especially of carbon dioxide and methane that have been observed in recent decades are directly related to human activities such as the burning of fossil fuels and the deforestation of tropical forests. Here is a summary of three types of GHGs carbon dioxide (CO 2), methane (CH 4), nitrous oxide (NO 2).

Carbon dioxide (CO2) is the single most important greenhouse gas emitted by human activities especially the burning of fossil fuel and deforestation. CO2 lingers in the atmosphere for hundreds if not thousands of years and so it directly impacts the global mean surface warming. The lingering effects of CO2 and other GHGs mean that most aspects of climate change will persist for centuries even if emissions of CO2 are stopped immediately.

Methane (CH4) is the second most important long-lived greenhouse gas. Approximately 60 percent comes from human activities like cattle breeding, rice agriculture, fossil fuel exploitation, landfills and biomass burning. There are huge stores of methane that may be released from the permafrost as global temperatures increase.

Nitrous oxide (N20) is the third most important long-lived greenhouse gas. Approximately 40 percent of N20 is emitted into the atmosphere from anthropogenic sources including biomass burning, fertilizer use, and various industrial processes. Its impact on climate, over a 100-year period, is 298 times greater than equal emissions of carbon dioxide. It also plays an important role in the destruction of the stratospheric ozone layer which protects us from the harmful ultraviolet rays of the sun.

Understanding the effects of GHGs is crucial if we are to tackle the catastrophic implications of climate change.