Nitrogen accounts for most of the Earth's atmosphere in volume. Oxygen ranks second. Together, nitrogen and oxygen compose 99 percent of the atmosphere's volume, with trace elements such as argon making up the rest.
Nitrogen is extremely stable in the atmosphere, where solar radiation and other natural phenomena react with other gases to create chemical reactions that affect the entire planet. Due to nitrogen's stability, it has accumulated in the atmosphere in great amounts over time. Despite nitrogen's abundance in the atmosphere, oxygen overall is around 10,000 times more common throughout Earth. Oxygen is a primary component of the Earth's surface, along with other elements, such as silicon, magnesium, sodium and calcium.