What percentage of the atmosphere is made up of nitrogen?

Nitrogen constitutes approximately 78% of the Earth's atmosphere, making it the most abundant gas present. This high percentage is significant because nitrogen plays a crucial role in various environmental and biological processes. It is an inert gas, which means it does not easily react with other substances under normal conditions, thereby stabilizing the atmosphere.

In addition, nitrogen is essential for the formation of amino acids, proteins, and nucleic acids in living organisms. Despite its prevalence, nitrogen does not contribute to the greenhouse effect significantly, which is a critical factor in climate science. The atmospheric composition of nitrogen varies slightly with altitude and geographical location but remains around the 78% mark.

Understanding the composition of the atmosphere is fundamental in fields such as meteorology, environmental science, and biology, as it affects air quality, weather patterns, and ecological systems.