Final answer:
Carbon dioxide (CO2) is the greenhouse gas that traps most of the outgoing infrared radiation due to its abundance in the Earth's atmosphere. Its increased emission, mainly from burning fossil fuels and deforestation, generates the greenhouse effect which causes global warming and climate change.
Step-by-step explanation:
The greenhouse gas that is responsible for trapping more outgoing infrared radiation, more so than any other greenhouse gases, is carbon dioxide or CO2. This is largely because of its abundance in the Earth's atmosphere. Increased emission of carbon dioxide primarily from anthropogenic sources such as burning of fossil fuels and deforestation, traps more heat which leads to an increase in the Earth's average temperatures. This process is known as the greenhouse effect, and it is a major contributor to global warming and climate change. Other significant greenhouse gases include Methane (CH4) and Nitrous oxide (N2O), but their overall effect is less than that of CO2 due to their lower concentration in the atmosphere.
Learn more about Greenhouse Gases