The Earth was created more than 4.5 billion years ago. During the beginning, the atmosphere contained large amounts of hydrogen and helium gas. Majority of them eventually escaped into space
After the beginning of the Earth's formation, the Earth was vert hot and a lot of volcanos were erupting, causing water vapor, carbon dioxide . These gases created atmosphere.
Large amounts of water vapor and NH3 molecules produced from erupting volcanoes . These components escaped to space making the atmosphere
About 3 billion years ago, after oceans and lakes were created, the first organisms appeared on earth known as stromatolites.
About 2-3 billion years ago, few of the living things began to use the sun's energy to turn CO2 gas and water into sugar and oxygen.
By 600 million years ago, a protective layer upper layer of the atmosphere called the ozone had formed.
About 400-500 million years ago, carbon dioxide levels increased and the first land plants appeared on Earth.
Homo sapiens have roamed the Earth for about 200,000 years, during that time, the atmosphere had 78% nitrogen and 21% oxygen
In modern times, humans have begun releasing more and more carbon dioxide into the air causing temperatures to rise as well