Atmospheric composition?

The Earth's atmosphere is composed of several gases, with nitrogen making up the majority at around 78%, followed by oxygen at around 21%. Other gases present in smaller amounts include argon, carbon dioxide, and trace amounts of other gases such as methane, neon, and helium. Water vapor is also present in varying amounts depending on location and weather conditions. Additionally, the atmosphere contains aerosols, which are tiny particles suspended in the air, as well as pollutants from human activities.

Composition of Earth's Atmosphere

Gases (% by volume):

- Nitrogen (N2): 78.08%
- Oxygen (O2): 20.95%
- Argon (Ar): 0.93%
- Carbon dioxide (CO2): 0.0407%
- Neon (Ne): 0.00182%
- Helium (He): 0.000524%
- Methane (CH4): 0.00018%
- Nitrous oxide (N2O): 0.000314%
- Hydrogen (H2): 0.00005%
- Krypton (Kr): 0.000114%

Variable Components:

- Water vapor: varies from 0 to 4% (highest near the surface)
- Ozone (O3): highly variable, concentrated in the stratosphere
- Aerosols: particles suspended in the air, such as dust, smoke, and sea salt
- Trace gases: include carbon monoxide, ammonia, sulfur dioxide, and nitrogen oxides

Layers of the Atmosphere:

- Troposphere (0-10 km):
- Contains most of the atmosphere's mass and water vapor
- Temperature decreases with altitude
- Stratosphere (10-50 km):
- Contains the ozone layer, which absorbs harmful ultraviolet radiation
- Temperature increases with altitude
- Mesosphere (50-85 km):
- Temperature decreases with altitude
- Meteors burn up in this layer
- Thermosphere (85-600 km):
- Temperature increases with altitude due to absorption of solar radiation
- Ionosphere layer within the thermosphere allows radio waves to bounce around the Earth
- Exosphere (600+ km):
- Outermost layer where particles escape into space
- Characterized by extremely low density