$partialdiff sub T$ [ NOAA NCEP-NCAR CDAS-1 MONTHLY Intrinsic MSL pressure ] climatology
| Longitude | grid: /X (degree_east) periodic (0) to (2.5W) by 2.5 N= 144 pts :grid | 
|---|---|
| Latitude | grid: /Y (degree_north) ordered (90N) to (90S) by 2.5 N= 73 pts :grid | 
| Time | grid: /T (months since 01-Jan) periodic (Feb) to (Jan) by 1.0 N= 12 pts :grid |