aquacrop/solution/evap_layer_water_content.py

import numpy as np
from typing import TYPE_CHECKING, Tuple

if TYPE_CHECKING:
    # Important: classes are only imported when types are checked, not in production.
    from aquacrop.entities.soilProfile import SoilProfile
    from numpy import ndarray



from ..entities.soilProfile import SoilProfile
    
def evap_layer_water_content(
    InitCond_th: "ndarray",
    InitCond_EvapZ: float,
    prof: "SoilProfile",
) -> Tuple[float, float, float, float, float]:
    """
    Function to get water contents in the evaporation layer

    <a href="https://www.fao.org/3/BR248E/br248e.pdf#page=82" target="_blank">Reference Manual: evaporation equations</a> (pg. 73-81)


    Arguments:

        InitCond_th (numpy.array): Initial water content

        InitCond_EvapZ (float): evaporation depth

        prof (SoilProfile): Soil object containing soil paramaters


    Returns:


        Wevap_Sat (float): Water storage in evaporation layer at saturation (mm)

        Wevap_Fc (float): Water storage in evaporation layer at field capacity (mm)

        Wevap_Wp (float): Water storage in evaporation layer at permanent wilting point (mm)

        Wevap_Dry (float): Water storage in evaporation layer at air dry (mm)

        Wevap_Act (float): Actual water storage in evaporation layer (mm)



    """

    # Find soil compartments covered by evaporation layer
    comp_sto = np.sum(prof.dzsum < InitCond_EvapZ) + 1

    Wevap_Sat = 0
    Wevap_Fc = 0
    Wevap_Wp = 0
    Wevap_Dry = 0
    Wevap_Act = 0

    for ii in range(int(comp_sto)):

        # Determine fraction of soil compartment covered by evaporation layer
        if prof.dzsum[ii] > InitCond_EvapZ:
            factor = 1 - ((prof.dzsum[ii] - InitCond_EvapZ) / prof.dz[ii])
        else:
            factor = 1

        # Actual water storage in evaporation layer (mm)
        Wevap_Act += factor * 1000 * InitCond_th[ii] * prof.dz[ii]
        # Water storage in evaporation layer at saturation (mm)
        Wevap_Sat += factor * 1000 * prof.th_s[ii] * prof.dz[ii]
        # Water storage in evaporation layer at field capacity (mm)
        Wevap_Fc += factor * 1000 * prof.th_fc[ii] * prof.dz[ii]
        # Water storage in evaporation layer at permanent wilting point (mm)
        Wevap_Wp += factor * 1000 * prof.th_wp[ii] * prof.dz[ii]
        # Water storage in evaporation layer at air dry (mm)
        Wevap_Dry += factor * 1000 * prof.th_dry[ii] * prof.dz[ii]

    if Wevap_Act < 0:
        Wevap_Act = 0

    return Wevap_Sat, Wevap_Fc, Wevap_Wp, Wevap_Dry, Wevap_Act