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20000427: Global model resolutions available via ldm

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  • Subject: 20000427: Global model resolutions available via ldm
  • Date: Thu, 27 Apr 2000 12:35:18 -0600
Greg,

The AVN and MRF are sent on a slew of grids via NOAAport:

The global thinned AVN grids are nominally 1.25x1.25 degrees. The -q 
option to dcgrib determiners the resolution to which you thicken them.
You can use -q "lin,dlat=1.25,dlon=1.25" for the full resolution

The global MRF are 5x5 degrees.

The both AVN and MRF are also sent on the regional AWIPS grids as you see on 
the 
pqact.conf examples, including the N. Hemisphere 380km grid.

The CONDUIT (NMC2) data feed carries the MRF/AVN grids from the OSO ftp server.
Both of these sets are available on the grid #3 (1x1 degree grid which
nominally would be 111km*cos(stdlat)) with the avn 0-84 hours and MRF 0-168
hours. The MRF is available on grid #2 (2.5x2.5 degree) from 0-384 hours.


The grids available on NOAAPORT are documented with the AWIPS letters they
designate for reference with the WMOgrib 388 manual:
eg:
# AVN model output 
# Grid #201 N. Hemisphere 381km: ^Y.A... KWBC.*(/mAVN|/mSSIAVN)
# Grid #202 CONUS         190km: ^Y.I... KWBC.*(/mAVN|/mSSIAVN)
# Grid #203 Alaska        190km: ^Y.J... KWBC.*(/mAVN|/mSSIAVN)
# Grid #211 CONUS          80km: ^Y.Q... KWBC.*(/mAVN|/mSSIAVN)
# Grid #213 CONUS          95km: ^Y.H... KWBC.*(/mAVN|/mSSIAVN)

# NOAAport MRF grids
# Grid #201 N. Hemisphere 381km: ^Y.A... KWBH
# Grid #202 CONUS         190km: ^Y.I... KWBH
# Grid #203 Alaska        190km: ^Y.J... KWBH
# Grid #204 Hawaii        160km: ^Y.K... KWBH
# Grid #205 Puerto Rico   190km: ^Y.L... KWB

The CONDUIT NMC2 feed data sets are shown at:
http://www.unidata.ucar.edu/staff/chiz/ncep_idd

and some examples of the various grid projections at:
http://www.unidata.ucar.edu/packages/gempak/examples/models/grids/

Steve Chiswell
Unidata User Support

On Thu, 27 Apr 2000, Greg Stossmeister wrote:
> Steve,
> 
>    Can you tell me what grid resolutions are available for the AVN/MRF
> model, Nothern Hemisphere, and Global via the ldm? Your pqact.conf file
> suggests 380 km for both, or 1.25 x 1.25, or 2.5 x 2.5 degree for
> thinned grids, yet I see other web sites quoting model resolution of 190
> km for N Hem. MRF and 110 km for AVN N Hem. Are these other resolutions
> available via ldm?
> 
> Thanks,
>    Greg
>