hcc_check - hydrostatic consistency criteria

INTERFACE:

    subroutine hcc_check()
DESCRIPTION:

This diagnostic routine calculates the hydrostatic consistency $h^c$ in each T-point and each layer. $h^c$ is defined as:

$\displaystyle h^c_{i,j,k}=\max\left\{
\vert\partial_xz_k\vert \frac{\Delta x}{\...
...ert\partial_yz_k\vert \frac{\Delta y}{\frac12(h_{i,j,k}+h_{i,j+1,k})}
\right\}.$ (108)

For the numerical calculation it is used here that $\Delta x$ and $\Delta y$ can be cancelled out each. For $h^c \leq 1$, the grid box is hydrostatically consistent, else it is called hydrostatically inconsistent. In the latter case, numerical problems can be expected for terrain-following coordinates when stratification is strong.

$h^c$ is stored in the 3d netcdf output file. USES:

    use domain, only: imin,imax,jmin,jmax,kmax,az,au,av,HU,HV
    use variables_3d, only: hn,hun,hvn,hcc
    IMPLICIT NONE
REVISION HISTORY:
    Original author(s): Karsten Bolding & Hans Burchard
LOCAL VARIABLES:
    integer                   :: i,j,k
    REALTYPE                  :: du1,du2,dv1,dv2
    REALTYPE                  :: x,y