FIM Frequently Asked Questions

Q: Distinguish between the horizontal resolution variations of G8, G9, etc. versions of FIM?
A: The resolutions most commonly used by the FIM are determined by the length of sides of associated rhombi divided by a power of two as follows:
  • FIM241 - G5 - average distance between neighboring cells = 241km - side of rhombi divided by 2**5 points
  • FIM120 - G6 - 128 km - side of rhombi divided by 2**6 points ( average distance between cell centers - 120.5km)
  • FIM60 - G7 - 64 km - side of rhombi divided by 2**7 points (average distance between cell centers - 60.4km)
  • FIM30 - G8 - 32 km - side of rhombi divided by 2**8 points (average distance between cell centers - 30.2km)
  • FIM15 - G9 - 16 km - side of rhombi divided by 2**9 points (average distance between cell centers - 15.1km)
  • FIM08 - G10 - 8 km - side of rhombi divided by 2**10 points (average distance between cell centers - 7.6km) .
Q: What global data is used to initialize the real-time FIM model forecasts?
A: GFS spectral grids interpolated to FIM icosahedral/isentropic-hybrid coordinates up to this point (11/2008).

Last modified on Tuesday, 13-Dec-2016 18:16:30 UTC