pvl_absoluteairmass
Determine absolute (pressure corrected) airmass from relative airmass and pressure
Contents
Syntax
AMa = pvl_absoluteairmass(AMrelative, pressure)
Description
Gives the airmass for locations not at sea-level (i.e. not at standard pressure). The input argument AMrelative is the relative airmass. The input argument pressure is the pressure (in Pascals) at the location of interest and must be greater than 0. The calculation for absolute airmass is:
Inputs
- AMrelative - The airmass at sea-level. This can be calculated using the PV_LIB function pvl_relativeairmass.
- pressure - a scalar or vector of values providing the site pressure in Pascal. If pressure is a vector it must be of the same size as all other vector inputs. pressure must be >=0. Pressure may be measured or an average pressure may be calculated from site altitude.
Outputs
- AMa - Absolute (pressure corrected) airmass
Example
Adjust airmass for elevation
AM = 1;
pressure = 80000; %Approximate air pressure at 2000 meters above sea level
AMa = pvl_absoluteairmass(AM, pressure)
AMa = 0.7895
References
[1] C. Gueymard, "Critical analysis and performance assessment of clear sky solar irradiance models using theoretical and measured data," Solar Energy, vol. 51, pp. 121-138, 1993.
See Also
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