solposx.refraction.sg2#
- solposx.refraction.sg2(elevation, pressure=101325.0, temperature=12.0)#
Atmospheric refraction correction based on the algorithm in SG2.
This function calculates the atmospheric refraction correction of the solar elevation angle using the method developed by Ph. Blanc and L. Wald [1].
- Parameters:
elevation (array-like) – True solar elevation angle (not accounting for refraction). [degrees]
pressure (numeric, default 101325) – Annual average atmospheric pressure. [Pascal]
temperature (numeric, default 12) – Annual average air temperature. [C]
- Returns:
Atmospheric refraction angle. [degrees]
- Return type:
np.array or pd.Series
Notes
The equation to calculate the refraction correction is given by:
\[\begin{split}\begin{align} & \frac{P}{1010} \cdot \frac{283}{273+T} \cdot \frac{2.96706 \cdot 10^{-4}}{\text{tan}(el+0.0031376 \cdot (el+0.089186)^{-1})} & \text{ for } el > -0.01 \text{ [rad]}\\ & -\frac{P}{1010} \cdot \frac{283}{273+T} \cdot \frac{1.005516 \cdot 10^{-4}}{\text{tan}(el)} & \text{ for } el < -0.01 \text{ [rad]} \end{align}\end{split}\]where \(el\) is the true solar elevation angle, \(P\) is the local air pressure, \(T\) is the local air temperature.
References