Atmosphere
Earth’s atmosphere is the layer of gases that surrounds Earth.
Earth’s atmosphere makes conditions on Earth suitable for living things.
It contains oxygen and other gases that you and other living things need to live.
It keeps the Earth warm enough for living things to live.
It keeps most of Earth’s surface warm enough for water to exist as a liquid.
It protects living things from dangerous radiation from the sun.
It prevents Earth from being hit by most meteoroids, or chunks of rock from outer space
What gases are in the atmosphere?
Nitrogen makes up about 78% of the air we breathe.
All organisms, including you, need nitrogen to grow & repair body cells
Oxygen is the second most abundant gas in the atmosphere. (21%) 78%
Plants and animals take oxygen from the air and use it to turn food into energy
Fuel needs oxygen to burn
The other 1% of the atmosphere is made up of trace (very small) amounts of other gases
Carbon dioxide is essential to life Carbon dioxide is essential to life. Plants must have it to produce food.
Water vapor is also present in the air Water vapor is also present in the air. The amount of water varies greatly from place to place and time to time
Air is also full of tiny particles of solids: dust, smoke, salt, and other chemicals.