Atmospheric Transmission

class pysolorie.atmospheric_transmission.AtmosphericTransmission(climate_type: str, observer_altitude: int, observer_latitude: float)

A class to model the atmospheric transmission.

To instantiate the AtmosphericTransmission class, provide the following three parameters.

Parameters:

• climate_type (str) – The type of climate.

• observer_altitude (int) – The altitude of the observer in meters.

• observer_latitude (float) – The latitude of the observer in degrees.

calculate_transmittance(day_of_year: int, solar_time: float) → float

Calculate the effective atmospheric transmission coefficient of the direct beam.

The effective atmospheric transmission coefficient of the direct beam is calculated using the formula:

\[\tau_b = a_0 + a_1 \times \exp\left(-\frac{k}{\cos(\theta_z)}\right)\]

- \(\tau_b\) is the effective atmospheric transmission coefficient of the direct beam

- \(a_0\), \(a_1\), and \(k\) are the components of clear-sky beam radiation transmittance

- \(\theta_z\) is the solar zenith angle

Parameters:

• day_of_year (int) – The day of the year.

• solar_time (float) – The solar time in seconds.

Returns:

The effective atmospheric transmission coefficient of the direct beam.

Return type:

float