Atmosphere Earths atmosphere is the layer of gases

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.

o All organisms, including you, need nitrogen to grow & repair body cells

• Oxygen is the second most abundant gas in the atmosphere. (21%) 21% 78%

o Plants and animals take oxygen from the air and use it to turn food into energy

o 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. Plants must have it to produce food.

• 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.