Earth's Early Atmosphere The Earth formed around 4.6 billion years ago from a cloud of gas and dust. The initial atmosphere contained gases released from volcan...
The Earth formed around 4.6 billion years ago from a cloud of gas and dust. The initial atmosphere contained gases released from volcanic eruptions, including water vapor, carbon dioxide, nitrogen, and very little oxygen. Over time, the composition changed dramatically.
As the Earth cooled, water vapor condensed to form the oceans. Photosynthesis by early life forms gradually increased oxygen levels, while carbon dioxide was removed and stored as fossil fuels. Today's atmosphere is roughly 78% nitrogen, 21% oxygen, and 0.04% carbon dioxide.
Certain gases like carbon dioxide, methane, and water vapor trap heat from the Sun, creating a natural greenhouse effect that makes Earth habitable. Without this effect, the planet's average temperature would be around -18°C instead of the current 15°C.
Human activities like burning fossil fuels and deforestation have increased greenhouse gas levels, trapping more heat and causing global temperatures to rise. The enhanced greenhouse effect disrupts climate patterns, melts ice caps and glaciers, raises sea levels, and increases extreme weather events.
To estimate your annual carbon footprint from everyday activities:
Take steps to reduce your carbon footprint by conserving energy, using renewable sources, and minimizing transport emissions.