Final answer:
The atmosphere at Earth's surface is primarily composed of 78% nitrogen, 21% oxygen, and 0.04% carbon dioxide.
Step-by-step explanation:
The atmosphere is composed of different gases in varying amounts. At Earth's surface, the principal components of the atmosphere are 78% nitrogen (N₂), 21% oxygen (O₂), and a small fraction of 0.04% carbon dioxide (CO₂), along with traces of other gases like argon and water vapor. Nitrogen and oxygen together make up 99% of the atmosphere, and the remaining 1% includes argon, carbon dioxide, and other trace gases. Although carbon dioxide constitutes a minor portion, its role in regulating Earth's temperature is significant. The average surface temperature on Earth is approximately 59 degrees Fahrenheit (15 degrees Celsius), according to NASA. However, the planet's average temperature is rising. The 10 warmest years across the entirety of recorded human history have all occurred since 2010.