Absolute optical air mass — trans_air_mass

Calculates the absolute optical air mass.

Usage

trans_air_mass_abs(...)

# Default S3 method
trans_air_mass_abs(datetime, lon, lat, elev, temp, ...)

# S3 method for class 'weather_station'
trans_air_mass_abs(weather_station, ...)

Arguments

...: Additional arguments.
datetime: POSIXlt object, date and time of the observation.
lon: Longitude in decimal degrees.
lat: Latitude in decimal degrees.
elev: Elevation above sea level in meters.
temp: Air temperature in °C.
weather_station: A weather_station object.

Value

Absolute optical air mass, unitless.

Details

The absolute optical air mass is calculated using the formula: $$M_{abs} = M_{rel} \cdot \frac{p}{p_0}$$ where $M_{rel}$ is the relative optical air mass, $p$ is the local air pressure, and $p_0$ is the standard pressure (1013.25 hPa). The air-mass approximation is cited to Bendix (2004) appendix material.

References

Bendix 2004, p. 247.

Examples

# Calculate absolute optical air mass
trans_air_mass_abs(
  datetime = as.POSIXlt("2023-08-06 12:00:00", tz = "UTC"),
  lon = 8.68, lat = 50.77, elev = 100, temp = 20
)
#> [1] 1.0834