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Qu about transmittance for snow over ice

The code for calculating transmittance (see below) does not match Equation 2 of Stroeve et al (2021). Transmittance for snow covered ice is defined as:

$$ T_s = i_{0,s}(1 - \alpha)\exp{[-\kappa_{s}(h_{s}-h_{ssl})]}\exp{[-\kappa_{i}h_{i}]} $$

However, in the code, the thickness of the surface scattering layer for wet snow ($h_{0} = 0.03 \mathrm{m}$) is not subtracted from $h_{s}$. Instead $\kappa_{s}$ is set to 40. Is Equation 2 wrong, or is the code wrong?

def get_f_att_snow(hsnow,hice,temperature):
# surface transmission layer thickness (m)
#surface transmission parameter
    # i_0_snw  =  0.45     # for wet snow (changed from 0.3)
    i_0_snw = 1.0       #for dry snow (changed from 0.3)
    i_0_ice   =  0.26     # for ice  (may change)  Changed to 0.26 from 0.3

# surface transmission layer thickness (m)
    h_0_snw  =  0.0     # for dry snow only
    h_0_ice   =  0.1    # for bare ice ice  (may change !)
    K_i  = 1
    K_s=7.               #for dry snow

    if (temperature > 0):  #wet snow case
        K_s=5.  #wet snow       #new coefficient for wet snow (used to be 7)
        i_0_snw = 0.45
        h_0_snw  =  0.03;     # for wet snow only
        if (hsnow > 0.) & (hsnow <= 0.03):  #correction for SSL < 0.03
            K_s=40.

#normal transmittance equation regardless of wet or dry snow
    f_att_snow  = i_0_snw*exp(-K_s*(hsnow))* exp(-K_i*hice) #normal extinction for SSL > 0.03

#modify if the snow depth is 0cm
    if (hsnow == 0):
        if (hice < 0.5):
           f_att_snow=exp(-K_i*hice)
        elif (hice < 0.1):
            K_i=12
            f_att_snow=exp(-K_i*hice)
        elif (hice >=0.5) & (hice <=0.8):
            hssl=(1./3.)*hice-(1./6.)
            f_att_snow=i_0_ice*exp(-K_i*(hice-hssl))
        else:
            f_att_snow=i_0_ice*exp(-K_i*(hice-h_0_ice))

    return(f_att_snow)

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