subroutine uEMEP_set_dispersion_sigma_simple(sig_z_00,sig_y_00,sigy_0_subgid_width_scale,subgrid_delta,delta_wind,x,sig_z,sig_y,sig_z_0,sig_y_0)
implicit none
real, intent(in) :: sig_z_00,sig_y_00,sigy_0_subgid_width_scale,subgrid_delta(2),delta_wind,x
real, intent(out) :: sig_z,sig_y,sig_z_0,sig_y_0
real ay,by,az,bz
real min_xy
!Set the psedo dispersion parameters for neutral conditions
!From Klug
!ay=0.32
!by=0.78
!az=0.22
!bz=0.78
!From Liu
!ay=0.64
!by=0.46!From Liu
!az=0.088!From Liu
!bz=0.72!From Liu 0.72
!Alternative ASME
!ay=0.14
!by=0.9
!az=0.22
!bz=0.85
!Update from K_z fitting
ay=0.32
by=0.78
!az=0.19
!bz=0.77
az=0.125
bz=0.85 !For z0=0.1, corresponding to the same as K_z for wind height at emission source of 1 m
az=0.245
bz=0.711 !For z0=0.3, corresponding to the same as K_z for wind height at average of emission source of 1 m and zc
az=0.21
bz=0.79 !For z0=0.3, corresponding to the same as K_z for wind height at emission source of 1 m
!Consistant with uEMEP_set_dispersion_params_PG needs to be fixed. Just one call to the parameters, one calle to the sigma calculation
az=0.2
bz=0.75
min_xy=(subgrid_delta(1)+subgrid_delta(2))/4.
!Set sig_y_0 to be half of the average x,y grid size
!Add this here ay*exp(by*log(min_xy)) to be the same as sig_z and the same as the Kz calculation
!Does not mean it is correct, just closer to the Kz which is perhaps not so correct
sig_y_0=sig_y_00+min_xy*sigy_0_subgid_width_scale+ay*exp(by*log(min_xy))
!Set sig_z_0 to be the size of the plume after travelling half of the grid size
sig_z_0=sig_z_00+az*exp(bz*log(min_xy))
!Set sig_y and sig_z = sig_0 + a*x^b +x*delata_wind
sig_y=sig_y_0+ay*exp(by*log(x))+x*abs(delta_wind)
sig_z=sig_z_0+az*exp(bz*log(x))
end subroutine uEMEP_set_dispersion_sigma_simple