[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

20050323: Gempak - Land mask for eta-212 gempak grid ???

Kevin,

The ETA 212 grids contain LAND/SEA mask which in
the grid file is LAND on a coordinate of NONE and 
level of 0. For example:
GFUNC = mask(sltk,sgt(land@0%none,0))

Gempak also provides 2 grid functions (see phelp gfunc)
LAND and SEA for masks of land and sea so you can do
GFUNC=mask(sltk,land) even if you don't have those
grids in your data set. Of course, you may prefer to use the
1/0 mask that is provided with your original data. The
GEMPAK functions will generate a landsea grid from $GEMTBL/grid/landsea.tbl
to match the grid in the calculation.

Steve Chiswell
Unidata User Support




>From: "Kevin Doty" <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200503232022.j2NKMdp8006605

>Institution: University of Alabama at Huntsville
>Package Version: 5.7.1
>Operating System: Linux
>Hardware Information: i386 Linux cluster
>Inquiry: Dear Colleague:
>
>I am using the Gempak files for the eta-212 grid (technically I guess they are
>  now called NAM grids).  Unless I am doing something stupid the soil temperat
> ures look reasonable over land but appear to be set to near freezing over wat
> er areas (like oceans, for example).  Is there a land-water mask available an
> ywhere that would enable me to "reset" these water values before I interpolat
> e to a finer grid?
>
>Many thanks,
>Kevin Doty
>
>
>
--
NOTE: All email exchanges with Unidata User Support are recorded in the
Unidata inquiry tracking system and then made publicly available
through the web.  If you do not want to have your interactions made
available in this way, you must let us know in each email you send to us.