The Earths atmosphere is an ocean of gases that surrounds the Earth. Gravity keeps the gases from drifting away from our planet into outer space. We live at the bottom layer of gases that surround Earth. Only at the bottom layer of the atmosphere is there enough air for plants and animals to survive.
The Earths atmosphere has structure and is divided into five distinct layers. Temperature is a major characteristic of the layers as well as the type of atoms found in each layer.
The troposphere is the layer next the the Earth which contains 80% of the atmosphere's mass. There are enough gases in this layer to support life on our planet.
Rising thermals of hot air and falling cool air mix the atmosphere so it is not layered. Weather occurs in this layer of the atmosphere. The jet stream is a narrow stream of fast moving air near the top of the troposphere.
The stratosphere lies above the troposphere. It contains 90% of the ozone on Earth in this layer. Ozone absorbs ultraviolet radiation produced by the Sun. The absorption of ultraviolet rays warms this layer. The air in this layer is very stable so jets often in the stratosphere.
The mesosphere lies about the stratosphere. The temperature decreases with height. The temperature at the top of the mesosphere averages -85 degrees Celsius (-120 degrees Fahrenheit). Meteors attracted by Earth's gravity usually burn up in this layer. Frozen water vapor form ice clouds in the mesophere.
The thermosphere lies about the exosphere. The temperature increases with height above the Earth. The low density of the gases allow the temperature to rise to 1500 degress Celsius (2,700 degrees Fahrenheit) in the individual gas molecules.
The International Space Station orbits in this layer. The layer has enough molecules that the solar wind reacts with the gas molecules and the auroras are generated.
Tectonic Plate Boundary Find out how and where tectonic plate boundaries form on our planet.
Plate Movements Do you know what are divergent plate boundaries, convergent boundaries and transform faults. Find out on this page.
Crustal Plates Find out how continental crust and oceanic crust forms on our planet.
The Earths Mantle Find out about the Earths mantle that contains 84% of the Earth's mass.
Earths Interior Find out about layers that have formed inside out planet and how they were discovered.
Earths Atmosphere Find out how the layers above Earth have formed and their importance to life on our planet.
Planet Earth Find out about the different layers that make up planet earth from the core to outer space.
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