Possible grid configurations in GEM


GEM offers the possibilities of running global uniform, global stretched (or variable) and limited area (LAM) grids.
You will find explications about the grid specification parameters here (login and password are 'science').
Click here to find out how to set up a grid.

Global uniform grid:

Grd_typ_S = 'GU' ,




GU: Global Uniform
Grd_ni = 60 , Grd_nj = 30 ,
           total number of grid points in x- and y-direction

  

Global YinYang grid:


Limited area grid (LAM):

LAM_grid.jpg
Grd_typ_S = 'LU' ,



         LU: Lam Uniform
Grd_ni = 20
, Grd_nj = 22
,

number of points in core area in x- and y-direction        
Grd_dx = 2.50 , Grd_dy = 2.50 ,

grid size in degrees
Grd_xlon1 = -94.10 , Grd_xlat1 = 41.20 ,

Rotation:
location in "real" coordinates of the center (lat=0°, lon=180°) of the new grid on the real globe
Grd_xlon2 = -87.00 , Grd_xlat2 = 53.50 ,

location in "real" coordinates of any other point on the grid equator
Grd_iref = 10
, Grd_jref = 11
,

Location of limited area in (rotated) grid:
reference point in LAM grid
Grd_latr = 0.0 , Grd_lonr = 180.0 ,

location of reference point in "grid" coordinates





Author: Katja Winger
Last update: January 2021