Human Biological Adaptability: Atmospheric Gasses

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The Earth's Atmosphere

Our planet's atmosphere consists of ten principle gasses and trace amounts of some other natural elements. The major components are more or less uniformly distributed up to 40-50 miles altitude in the relative amounts shown in the following table.

Gas Percent of
the Atmosphere

   Nitrogen
Oxygen
   Argon
   Neon
    Helium
Methane
   Krypton
   Hydrogen
Nitrous oxide
Xenon
        78.084
        20.946
          0.934
          0.0018
          0.000524
          0.0002
          0.000114
          0.0005
          0.00005
          0.0000087

In addition, our atmosphere contains regionally varying amounts of water vapor, ozone, carbon dioxide, sulfur dioxide, nitrogen dioxide, and some other man-made gasses. The amounts of these latter gasses also vary with altitude, time of year, and weather conditions.

Return

Gas	Percent of the Atmosphere

Nitrogen Oxygen Argon Neon Helium Methane Krypton Hydrogen Nitrous oxide Xenon	78.084 20.946 0.934 0.0018 0.000524 0.0002 0.000114 0.0005 0.00005 0.0000087