Final answer:
Methane (CH4) is a greenhouse gas that is also a major component of natural gas. It is a very potent greenhouse gas, contributing significantly to the enhanced greenhouse effect.
Step-by-step explanation:
The greenhouse gas that is also a major component of natural gas is methane (CH4). Methane is a very potent greenhouse gas and is primarily responsible for approximately 20 percent of the enhanced greenhouse effect. Natural gas, which meets a significant portion of world energy needs, is mainly composed of methane, and there are two types: biogenic gas from the anaerobic decay of organic matter and thermogenic gas from the compression of organic matter deep underground.
Other greenhouse gases include carbon dioxide, nitrous oxide, and various synthetic gases like hydrofluorocarbons, but methane is one of the most critical due to its high effectiveness in warming the Earth's atmosphere per molecule compared to carbon dioxide.
It is also noteworthy that human activities have significantly increased the concentration of methane in the atmosphere since the beginning of the industrial era. Hence, methane's role in contributing to global warming is magnified by these activities, which include the use of fossil fuels, among others.