Layers of the Atmosphere

The atmosphere is composed of five main layers—the troposphere, stratosphere, mesosphere, thermosphere and exosphere. Each layer has different characteristics.

We live in the troposphere. This is the densest layer, containing gas, water vapor, pollution and most weather elements. As altitude increases in the troposphere, the temperature gets colder.

The stratosphere is above the troposphere. Higher altitudes of the stratosphere are warmer because they are heated by the sun’s radiation. The ozone layer that filters harmful ultraviolet radiation is found in the stratosphere.

The mesosphere is the coldest layer of atmosphere, with some temperatures as low as minus 100 degrees Celsius. Meteoroids burn up in this layer and leave behind trails of glowing gases known as shooting stars.

The thermosphere is located in the upper atmosphere, and the temperature gets warmer as the altitude increases. Air particles in this layer are not dense, but they move very quickly. The ionosphere is a part of the thermosphere that contains charged gas particles that create natural light displays called auroras.

The exosphere is the outermost layer of the atmosphere. Only very light gases, like hydrogen, helium and individual oxygen molecules are found here.