Earth's atmosphere

Troposphere Fundamentals

Our lowest layer, where weather occurs. Height lowers temperature and air pressure.

Stratosphere Ozone Shield

Ozone protects against UV radiation from tropopause to 50 km. CFCs cause the "Antarctic ozone hole.

 Mesosphere Chill Zone

After stratosphere, mesosphere reaches -90°C at mesopause.


Absorption of solar energy raises mesosphere temperatures. Ionosphere over 80 km affects radio wave reflection and absorption.

Escape to the Exosphere

Starting at 500 km, the exosphere has few oxygen and hydrogen atoms. Some escape into space; few collisions.

Charged particles produce Van Allen belts in Earth's magnetic field.

Earth Protector

Air Mass Insights

Earth's atmosphere weighs around 5×10^15 tonnes, or 1/200,000 of its total mass. Water-vapor-induced annual fluctuations.

Mass Estimation Precision

the mean mass is 5.1480×10^18 kg, with slight yearly fluctuations due to water vapour.