Re: [gembud] determining model terrain height

• To: <gembud@xxxxxxxxxxxxxxxx>
• Subject: Re: [gembud] determining model terrain height
• From: "Evan Lowery" <elowery@xxxxxxxxxxxx>
• Date: Mon, 8 Jun 2009 07:22:10 -0400

Robert,

 

The GFS/NAM/RUC have the following grids which I believe is an approximation
of the surface elevation (correct me if I'm wrong).

 

GFS

grid: 201:19947514:D=2009060800:HGT:sfc:kpds=7,1,0:6hr fcst:winds are
N/S:"Geopotential height [gpm]
source:
http://nomads.ncdc.noaa.gov/data/gfs-avn-hi/200906/20090608/gfs_3_20090608_0
000_000.inv (daily 0Z GFS run)

 

NAM

grid: 4:1314242:D=2009060800:HGT:sfc:kpds=7,1,0:anl:winds in grid
direction:"Geopotential height [gpm] (daily 0Z NAM run)

source:
http://nomads.ncdc.noaa.gov/data/nam/200906/20090608/nam_218_20090608_0000_0
00.inv (daily 0Z NAM run)

 

RUC

290:26084294:D=2009060800:HGT:sfc:kpds=7,1,0:anl:winds in grid
direction:"Geopotential height [gpm]

source:
http://nomads.ncdc.noaa.gov/data/ruc/200906/20090608/ruc2_252_20090608_0000_
000.inv (daily 0Z RUC run)

 

The "inv" files are generated using wgrib2.
(http://www.cpc.noaa.gov/products/wesley/wgrib2/).  Hope this helps you out.
Let me know if you have any more questions.

 

Regards,
Evan

 

Seems like I should know this, but I don't.  I wrote a gdvint script that 

interpolates GFS/NAM/RUC data to height above ground for 300 meters above 

ground.  It then occurred to me that I don't know what the particular model 

thinks is the elevation at my chosen grid point.  I did a gdinfo for the 

nam212, gfs212, and ruc255 and did not see anything that might give me model


terrain height at a given grid point (say using gdpoint).  Does anyone know
how 

to do this?

 

Thanks,

Robert Mullenax

CSBF/NMSU