[RegCNET] layer thickness in RegCM4

[Graziano Giuliani]

On 10/10/17 22:14,  KOMKOUA MBIENDA A. J. wrote:
> Dear All,
> 
> I want to use AOD in each layer by using AEXT8 in OPT files.
> Therefore, I would like to know the value of each layer thickness in
> RegCM4.
[...]

In recent RegCM the variable deltaz is added to the model OPT files. If
not the case, you can always compute it using the hydrostatic approx as
in the following snippet:

z(kzp1) = 0.0
do k = kz, 1, -1
  cell = ptop / ps
  z(k) = z(k+1) + R/g * t(k) * log((sigma(k+1)+cell)/(sigma(k)+cell))
end do

do k = 1, kz
  deltaz(k) = z(k) - z(k+1)
end do

where ptop is top pressure, ps is pstar (surface pressure - ptop), R is
the dry air gas constant, g is the gravity acceleration, t is the
temperature in K, sigma is the adimensional vertical coordinate.

The temperature is in the ATM file. Values for the constants as used by
RegCM are:

R = 287.0569248 (J/kg/K)
g = 9.80665 (m/s^2)

G.

-- 
Graziano Giuliani - Earth System Physics Section
The Abdus Salam International Centre for Theoretical Physics
Strada Costiera 11 - I - 34151 Trieste Italy