GPSRO Usage at Environment Canada

Models assimilating RO

• Global Deterministic (GD):
  • horiz: 1025×800 latlon
  • vertical: 81L hybrid
  • forecasts: 00Z (to 240h) and 12Z (to 180h)
• Global Ensemble (GE):
  • horiz: 800×400 latlon
  • vertical: 75L hybrid
  • forecasts: 00Z (to 240h) and 12Z (to 180h)
• Regional (North America) Deterministic (RD):
  • horiz: 978×1010 tilted
  • vertical: 58L hybrid
  • forecasts: 00Z and 12Z to 48h
  • 06Z and 18Z to 54h
• Regional (North America) Ensemble (RE):
  • horiz: 600×635
  • vertical: 50L hybrid
  • forecasts: 00Z and 12Z to 72h

 Data assimilation method

• Global Deterministic: 4d , 4/day, 6h (+/- 3h)
• Global Ensemble: enkf, 4/day, 6h (+/- 3h)
• North America Deterministic: 3d , 4/day, 4.7h (-3h to +1h40m)
• North America Ensemble: no assimilation
• Cutoff times (from synoptic times):

RO quantity assimilated

• Refractivity
• 1D operator
• Tangent point drift not included
• Vertical thinning: 1 datum/ vertical km
• RO is not bias-corrected
• RO is anchor to radiances (which do have dynamic bias correction)

 Observation error characteristics

• Dynamically determined within each profile from its (O-B) shape

Impact

• 2nd largest impact/datum (after RS)