Name

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STANDARD_ATM

Purpose

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This function calculates the pressure at a given altitude in the
troposphere, assuming a uniform, dry atmosphere.

Category

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PHYSICS

Calling Sequence

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Result = STANDARD_ATM( Input )

Inputs

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Input: The altitude, in metres, at which the pressure should be
calculated. Of type floating point. If ALTITUDE is set, this
is instead the pressure at which the altitude should be
calculated.

Keyword Parameters

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ALTITUDE: If set, the function calculates the altitude of a given
pressure level. The default is the reverse.
BAR: If set, the pressure unit is a bar. The default is Pa.
CELSIUS: If set, the temperature units are in degrees Celsius. The
default is Kelvins.
HPA: If set, the pressure unit is a hPa. The default is Pa.
KILO: If set, the units are kPa and km. The default is Pa and m.
TEMPERATURE: If set, the function returns the average temperature, in
K, at the given altitude.

Outputs

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Result: Returns the pressure at the given altitude.

Uses

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CONSTANTS.pro

Procedure

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This function is modelled after StdAtm at
http://hurri.kean.edu/~yoh/calculations/hydrostatic/hydrostatic.html.

Example

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Calculate the pressure, in kPa, at 2757m altitude.
result = STANDARD_ATM( 2.757, /KILO )

Modification History

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  Written by: Daithi A. Stone (stoned@uvic.ca), 2001-08-13
Modified: DAS, 2002-05-16 (fixed bugs in GAMMA and unit options)
Modified: DAS, 2002-08-12 (complies with CONSTANTS.pro revision)