4.4_Atmosphere

Atmosphere

The layer of gases surrounding Earth, composed mainly of nitrogen, oxygen, argon, and carbon dioxide.

Nitrogen (N2)

The most abundant gas in the atmosphere, constituting about 78%.

Oxygen (O2)

A vital gas produced by photosynthesis, making up about 21% of the atmosphere and essential for respiration.

Troposphere

The lowest layer of the atmosphere where weather occurs, located from 0-16 km above the Earth's surface.

Stratosphere

The second layer of the atmosphere, 16-60 km up, containing the ozone layer that absorbs UV rays.

Mesosphere

The middle layer of the atmosphere, 60-80 km up, where temperatures decrease.

Thermosphere

The layer of the atmosphere that absorbs solar radiation, leading to high temperatures.

Exosphere

The outermost layer of the atmosphere where it merges with outer space.

Ozone (O3)

A molecule found in the stratosphere and troposphere, important for filtering UV radiation but harmful at ground level.

Temperature Gradient

The rate of temperature change in the atmosphere with altitude.

Atmospheric Pressure

The force exerted by the weight of air in the atmosphere, which decreases with altitude.