$partialdiff sub Y$ mean [ NOAA NCEP-NCAR CDAS-1 MONTHLY Intrinsic PressureLevel rhum climatology ]
| Latitude | grid: /Y (degree_north) ordered (88.75N) to (88.75S) by 2.5 N= 72 pts :grid | 
|---|---|
| Pressure | grid: /P (mb) ordered [ (1000) (925) (850) (700) (600) (500) (400) (300)] :grid |