Earth's Atmospheric Layers Overview

Overview

This lecture covers the five main layers of Earth's atmosphere, their characteristics, key functions, and relevant facts.

The atmosphere consists of five main layers: troposphere, stratosphere, mesosphere, thermosphere, and exosphere.
The troposphere is the lowest layer, where weather happens, extending 4-10 miles above the Earth's surface.
In the troposphere, temperature decreases as altitude (height above ground) increases.
The stratosphere is above the troposphere, reaching up to 30-35 miles above Earth.
The temperature in the stratosphere rises with altitude.
The ozone layer is within the stratosphere and absorbs harmful UV rays from the sun.
Commercial airplanes typically fly in the stratosphere due to lack of weather disturbances.
The mesosphere extends up to 50 miles from the Earth's surface.
Most meteors burn up in the mesosphere upon entry.
The thermosphere follows, with very thin air and temperatures that are extremely hot.
The thermosphere extends up to about 400 miles above Earth and contains the ionosphere in its lower part.
In the ionosphere, many atoms become ionized, and it is important for transmitting radio waves.
The exosphere is the outermost atmospheric layer, extending up to 6,200 miles from Earth.
The exosphere has very thin air.

Troposphere — Lowest atmospheric layer where weather occurs; temperature decreases with altitude.
Altitude — Height of an object or point in relation to ground level.
Stratosphere — Second atmospheric layer; contains the ozone layer and airplanes; temperature increases with altitude.
Ozone Layer — Part of the stratosphere that absorbs UV radiation.
Mesosphere — Third atmospheric layer where meteors burn up.
Thermosphere — Fourth layer with thin air and very high temperatures; includes the ionosphere.
Ionosphere — Region within the thermosphere with ionized atoms, aiding radio wave transmission.
Exosphere — Outermost layer of the atmosphere with extremely thin air.