Sea level pressure — sea_level_pressure • atmoschem.process

Estimate sea level pressure from local pressure, temperature, and height using the barometric formula.

sea_level_pressure(press, temp, height)

Arguments

press: Pressure in millibars.
temp: Temperature in Celsius.
height: Height above sea level in meters.

Value

Estimated sea level pressure.

Details

We estimate the sea level pressure using the barometric formula,

$$P = P_0 (\frac{T_0}{T})^\frac{Mg}{R^*L}$$

where $P$ is pressure, $T$ is temperature (in Kelvin), $H$ is height, and $L$ is the temperature lapse rate. Variables with subscript 0 are the same at sea level. Substituting $T_0 = T - LH$, we can solve for $P_0$ in terms of pressure, temperature, and height:

$$P_0 = P (\frac{T}{T - LH})^\frac{Mg}{R^*L}$$

The values of physical constants are taken from COESA (1976) :

$L$ (lapse rate): -.0065 K/m
$M$ (molar mass of air): 0.0289644 kg/mol
$g$ (gravitational acceleration): 9.80665 m/s^2
$R^*$ (universal gas constant): 8.31432 J/(mol K)

References

COESA (1976). “U.S. Standard Atmosphere, 1976.” https://ntrs.nasa.gov/citations/19770009539.

Examples

# estimate sea level pressure at the Whiteface Mountain summit
sea_level_pressure(800, 30, 1483.5)
#> [1] 943.1199