How to install grib2ctl.pl and wgrib in linux

Dear All,

Now we are going to see how to install wgrib and grib2ctl in our linux machine.

step 1:

First of we need to install GRADS

http://grads.iges.org/grads/downloads.html

From the above link we can get the source.

In ubuntu $ sudo apt-get install grads

step 2:

From the below site we can download the grib2ctl.pl perl source code
http://www.cpc.ncep.noaa.gov/products/wesley/grib2ctl.html

Look in the bottom of the page.

Try to open all the above links in firefox not in chrome.

Download that grib2ctl.pl source code from here ftp://ftp.cpc.ncep.noaa.gov/wd51we/wgrib.scripts/grib2ctl.pl use firefox.

save that file as grib2ctl.pl .

step 3:

Go to the below link to download the wgrib c code
http://www.cpc.ncep.noaa.gov/products/wesley/wgrib.html

From here you can download the wgrib.c source code ftp://ftp.cpc.ncep.noaa.gov/wd51we/wgrib/wgrib.c use firefox.

save it as wgrib.c.

$ gcc wgrib.c -o wgrib

We are generating the wgrib object file.

$ sudo cp wgrib /usr/local/bin/

We are moving that binary wgrib file in to the system path /usr/loca/bin

step 4:

Now open the grib2ctl.pl file,

1. Look for the line:
   $wgrib=’wgrib’;
   and change it to point to your copy of wgrib. For example,
   $wgrib=’/usr/local/bin/wgrib’;
2. (Optional) Look for the line:
   $pdef_dir=’/usr/local/lib/grads’;and change it to point to your grads directory. In the future, some unviewable grids (ex. thinned grids, native eta) will be handled by interpolation files.
3. Don’t forget to make the program executable (chmod 755 grib2ctl.pl) and put it on your PATH. i.e $ sudo cp grib2ctl.pl /usr/local/bin/

Thats it … !

Now you can access the grib2ctl.pl from the bash shell (terminal) itself.

Try the following usage of grib2ctl with your analysis and forecasting binary grib files.

Usage

For analyses:

$ grib2ctl.pl grib_file >grib_file.ctl
$ gribmap -i grib_file.ctl -0 <– this is a zero
$ grads
Landscape mode? (no for portrait):

ga-> open grib_file.ctl

For forecasts:

$ grib2ctl.pl -verf grib_file >grib_file.ctl
$ gribmap -i grib_file.ctl

$ grads
Landscape mode? (no for portrait):
ga-> open grib_file.ctl

To understand, what is grib and ctl file formate

grib is the one of binary file formate to store the analysis and forecast data in some kind of structured manner.
ctl means control file in ascii formate. we can read it. Both these formates are usually used in atmospheric and meteorological departments.

The generated ctl files can be read and visualized by GRADS , CDAT and other meteorological softwares.

Both Grads and CDAT are open source software.

More over many other foss applications are available for the same kind of stuff.

In that one more thing is cdo – Climate Data Operators

you can install cdo in ubuntu by $ sudo apt-get install cdo

Thanks,
Arulalan.T