NOAA NCEP-NCAR CDAS-1 MONTHLY Intrinsic PressureLevel phi
Resolution: 2.5x2.5; Longitude: global; Latitude: global; Pressure: [10 mb,1000 mb]; Time: [Jan 1949,May 2021]; monthly
Covar. v and specific hum
(m/s) [ Longitude Latitude Pressure Time ]