Global Domain
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Real Time Standard Forecast
Plots of Interest
Select plots can be seen here for the global domain:
the model is still in test mode, so there could be
an occasional missed forecast or outputs to be improved upon.
The model uses a plattecarre projection (latlon)
on a (finite difference) Cgrid.
Currently, runs are usually done on grids of (degrees, lon X lat):
 0.93750 X 0.75000 (default, about 80x80km at mid latitudes),
 1.12500 X 0.84375... or
 1.40625 X 1.12500 or
 1.87500 X 1.40625
See plots
to know which resolution was used for the current forecast
(indicated in upper right part of plots).
Above a critical
latitude, Fourier Filtering (polar filtering)
of mass variables is used (i.e. the product of the
specific density and T, u, v
are filtered, along with psurf).
The latitudinal grid spacing has been selected such that
grid boxes are approximately squares at the cutoff
latitude (generally in midlatitudes).
The initial fields and 3.5 day forecasts
(0 to 84 hour forcasts, every 12 hours)
can be seen below by clicking on
the appropriate links (below).
The model uses the same physics and dynamic core as the
limited area model version of ASP.
The global model uses a larger grid spacing than the LAM
model, so fields are slightly more smooth.
The model is initialized using input GFS data
(interpolated to the ASP grid), and a short forward and
backward adiatatic integration using a digital filter.
The model uses bigbrother assimilation of
T, u, v
and psurf during the first
12h of the forecast (using GFS forecast data), which is
then tapered off by 18h.
The description of the global grid, polar filtering,
boundary conditions etc...can be found in the
ASP documentation pages.
Feel free to send any comments (aaron.a.boone@gmail.com).
Sub Domains
Several sub domains on the global grid are shown:
NA=North America, EU=Europe, AF=Africa, and EA=East Asia.
Hemisphere=a satellite view of a hemisphere (using an
Orthographic Projection). The Default is centered over the central
north Atlantic.
Note that global plots might, at times, extend beyond the
3.5 default forecast (out to 5, 7 or even 10 days).
Field  NA  NA  EU  EU  EA  EA  AF  AF  Hemisphere 
300 Hgt, WindV, WindS 
036h 
4884h 
036h 
4884h 
036h 
4884h 
036h 
4884h 
084h 
500 Hgt, WindV, AbsVort 
036h 
4884h 
036h 
4884h 
036h 
4884h 
036h 
4884h 
084h 
700 Hgt, WindV, VVel 
036h 
4884h 
036h 
4884h 
036h 
4884h 
036h 
4884h 
084h 
850 Hgt, WindV, Tair 
036h 
4884h 
036h 
4884h 
036h 
4884h 
036h 
4884h 
084h 
Lowest model level T, RH, and wind vectors 
036h 
4884h 
036h 
4884h 
036h 
4884h 
036h 
4884h 

PSurf, Total Precip, 5001000 Thck 
036h 
4884h 
036h 
4884h 
036h 
4884h 
036h 
4884h 
084h 
PSurf, Froz Precip, 5400m Thck, 850mb0deg 
036h 
4884h 
036h 
4884h 
036h 
4884h 
036h 
4884h 

700 Hgt, 850500 mb RHavg 
036h 
4884h 
036h 
4884h 
036h 
4884h 
036h 
4884h 

500 Hgt, Surface Pressure 
036h 
4884h 
036h 
4884h 
036h 
4884h 
036h 
4884h 
084h 
Key:
 Hgt = Geopotential Height (m)
 WindS = Wind speed
 WindV = Wind vectors
 Tair = Air Temperture
 AbsVort = Absolute Vorticity
 VVel = Vertical velocity defined as omega (+
for upward motion)
 Qair = Specific Humidity
 Precip = Cummulative total (convective and
stratiform) Precipitation for
each forecast interval
 Thck = Pressure thickness
 Lowest Model Level = Currently corresponds
to eta=0.997 or
about 30 m above the ground (less in high altitude zones)
 NearSurf = 2m Tair and 10m Wind speed (i.e. at
the level of standard measurements)
 TSurf = Surface temperature: combined surface
vegetation and upper thin soil layer or SST
(Sea Surface Temp.)
Standard Atmosphere: PressureHeight correspondence
As a reference, the pressure levels above correspond to
the approximate heights
below in meters (and feet) for a
standard
atmosphere.
This can be used as a rough estimate of the height of the
dust plumes shown in the plots above.
Pressure (HPa or mb)  height (meters)  height (feet) 
100  16170  53051 
200  11770  38616 
300  9160  30053 
500  5570  18274 
700  3000  9843 
850  1460  4790 
925  760  2493 
1013.25  0  0 
Please send any comments to aaron.a.boone@gmail.com
Disclaimer
Please note that this page has nothing to do with
my employer, CNRS, or where I am employed, at the National
Center for Meteorological Research (Centre National de
Recherches Meteorologiques: CNRM) at MeteoFrance.
The opinions expressed herein are my own, and are not a
reflection of those where I work or of my employer.
Acknowledgement
Finally, a special thanks is extended to the United States
National Centers for Environmental Prediction (NCEP)
for making
GFS analysis and forecast data freely available in near real time,
which makes applications and research such as this possible.
