Dear ferreter's
I am having big problems in calculating the meridional overturning
for the POP ocean model of CCSM3. POP is defined on a curvilinear
grid so I figured that the way to do this is to first convert this grid
to a rectangular grid with Ferret's CURV_TO_RECT function.
I created a file map_deg_control.nc containing the weights for the
mapping with help of the user's guide.
After that I calculated the MOC with the .jnl script below. It is possible to let POP
output the MOC field so I was able to check if my own calculated MOC
was good but the fields are very different.
I think that something goes wrong with the conversion from curvilinear to
a rectangular grid so I looked for other ways to do this e.g. with NCO or CDO
but I could not find anything.
Are there people who have experience with the calculation of the MOC for POP output from CCSM3 ?
Kind regards,
Michael
!------------------------------------
! my moc.jnl script
!------------------------------------
! read file containing meridional velocity VVEL
use reversed_rotation_pd.pop.h.0300-01_vvel_world.nc
! Determine velocity on rectangular LON-LAT grid
! Apply mapping to variables
USE "umap_deg_control.nc"
LET vnew = curv_to_rect(VVEL[D=1], map[D=2])
! Save variable + grid to a file
save/clobber/file=basinshelp.nc vnew
! Now determine moc
cancel data/all
cancel var/all
use basinshelp.nc
! divide by 1.e8 for conversion from cm^3/sec to Sv
let vdash = vnew/1.e8
! do the integration
let moc = vdash[x=@din,z=@iin] - vdash[x=@din,z=@din]
shade/nolab moc
contour/ov/nolab moc
label/nou 4 6.5 0 0 .25 MOC (Sv)