Standard atmosphere
# Standard atmosphere

Standard atmosphere may refer to:

* A standard reference value for air pressure:
   * Atmosphere (unit), an approximation of the value at sea level
   * Atmospheric pressure, other reference values
* One of various static atmospheric models of how atmospheric pressure, density, and temperature vary with altitude, such as:
   * The U.S. Standard Atmosphere, a series of models that give values for pressure, density, and temperature over a range of altitudes
   * The International Standard Atmosphere (ISA), an international standard model, defining typical atmospheric properties with altitude, at mid-latitude
