MM5 OnLine Tutorial : TERRAIN

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In this example, 4 domains will be created, 2 of which will be on the same level (MAXNES=4). (The central lon/lat remains the same as for the SOC case).

Domain 1

39x45 grid points (NESTIX(1)=39 ; NESTJX(1)=45);
with a grid distance of 90 km (DIS(1)=90);
domain 1 is the mother of both domain 2 (NUMNC(2)=1) and domain 3 (NUMNC(3)=1)

Domain 2

40x49 grid points (NESTIX(2)=40 ; NESTJX(2)=49);
with a grid distance of 30 km (DIS(2)=30);
its lower left corner point is positioned at grid point 20,23 (NESTI(2)=20 ; NESTJ(2)=23) inside its mother domain (its mother is domain1 as numnc(2)=1)

Domain 3

40x49 grid points (NESTIX(3)=40 ; NESTJX(3)=49);
with a grid distance of 30 km (DIS(3)=30);
its lower left corner point is positioned at grid point 6,6 (NESTI(3)=6 ; NESTJ(3)=6) inside its mother domain (its mother is domain1 as numnc(3)=1)
as domains 2 and 3 are on the same level, care must be taken that they do not overlap

Domain 4

43x46 grid points (NESTIX(4)=43 ; NESTJX(4)=46);
with a grid distance of 10 km (DIS(4)=10);
its lower left corner point is positioned at grid point 15,25 (NESTI(4)=15 ; NESTJ(4)=25) inside its mother domain (its mother is domain2 as numnc(4)=2)

Domains 5 and 6 are inactive.

 MAXNES = 4, ; NUMBER OF DOMAINS TO PROCESS
 NESTIX = 39, 40, 40,  43, 211, 221, ; GRID DIMENSIONS IN Y DIRECTION
 NESTJX = 45, 49, 49,  46, 211, 221, ; GRID DIMENSIONS IN X DIRECTION
 DIS =   90.,30.,30.,10.0, 1.0, 1.0, ; GRID DISTANCE
 NUMNC =   1,  1,  1,   2, 4, 5,     ; MOTHER DOMAIN ID
 NESTI =   1, 20,  6,  15, 45, 50, ; LOWER LEFT I OF NEST IN MOTHER DOMAIN
 NESTJ =   1, 23,  6,  25, 55, 50, ; LOWER LEFT J OF NEST IN MOTHER DOMAIN

	If you are working with 2-way nested domains (i.e. a ratio of 3:1), domains 2 - 10, must have 3x+1 grid points (x being any number), thus in the example above, domain2 can have 40 grid points in the Y direction (3*13+1), but it cannot have 39 or 41 grid points. This is to ensure that the nests' last grid point coincides with a grid point on the mother domain.
	A nest MUST always be at least 5 grid points away from it mother's boundaries. So the minimum you may set NESTI/NESTJ to is 6. Care must also be taken that the right and top nest boundaries stay at least 5 grid points away from it mother's boundaries.
	Nests on the same level may not overlap or touch.
	2-way nested domains MUST have a grid ratio of 3:1 i.e., if the mother domain's grid distance is 10km, the nest's grid distance MUST be 3.333, and NOT 3km.