EARTH'S ATMOSPHERE            www.tecnozono.com

  

Composition of Earth's atmosphere

An atmosphere (from Greek ατμός - atmos, 'vapor' + σφαίρα - sphaira, 'sphere') is a layer of gases that may surround a material body of sufficient mass.

A particular environment or surrounding influence; "there was an atmosphere of excitement".

Standard atmosphere: a unit of pressure: the pressure that will support a column of mercury 760 mm high at sea level and 0 degrees centigrade.

Principal layers of the atmosphere

Earth's atmosphere can be divided into five main layers. These layers are mainly determined by whether temperature increases or decreases with altitude. From lowest to highest, these layers are:

• Troposphere
• Stratosphere
• Mesosphere
• Thermosphere
• Exosphere

Composition of the Atmosphere

The atmosphere is primarily composed of:

• Nitrogen (N2, 78%)
• Oxygen (O2, 21%)
• Argon (Ar, 1%)

A myriad of other very influential components are also present which include the water (H2O, 0 - 7%), "greenhouse" gases or Ozone (O, 0 - 0.01%), and Carbon Dioxide (CO2, 0.01-0.1%).