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20030805: sample NIDS data to test ARPS assimilation code

>From:  David Garrana Coelho <address@hidden>
>Organization:  UFRJ
>Keywords:  200307221908.h6MJ8JLd020160 ldm-mcidas NIDS ARPS

Hi David,

re:
>(http://www.caps.ou.edu/ARPS) model thru its data assimilation package
>called ADAS (link on the ARPS page). It haves among his utilities, a tool
>called 88d2arps, used to convert 88d format radar data into ADAS readable
>format. And inside this tool, there is a small piece of code (which I
>managed to compile successfully) called nids2arps, who in turn, claims to
>be able to "Remaps NIDS Level-III data to ARPS grid". Sadly (and that's my
>main concern in it all) it haves no documentation, no help or readme
>file. My hopes are to find a NIDS file which I can test this piece of code
>and try to find out how it works.

After getting into the office and rereading the paragraph above, I
relized that the information I gave you about the ldm-mcidas package
was incomplete:  ldm-mcidas-2003.tar.Z contains a set of NIDS data
files that you could use in your tests.  Here is the information
again:

ftp ftp.unidata.ucar.edu
  <user> anonymous
  <pass> address@hidden
  cd pub/ldm-mcidas
  binary
  get ldm-mcidas-2003.tar.Z
  quit

zcat ldm-mcidas-2003.tar.Z | tar xvf -
cd ldm-mcidas-2003/src/decode

The files with the '.raw' suffic are uncompressed NIDS data files that
I use to test the conversion routine 'nids2area' (converts NIDS format
data into McIDAS AREA files):

vil.raw   - vertically integrated liquid water
vel4.raw  - radial velocity at tilt 4
vel3.raw  - radial velocity at tilt 3
vel2.raw  - radial velocity at tilt 2
vel1.raw  - radial velocity at tilt 1
tops.raw  - echo tops
pret.raw  - storm total precipitation
pre3.raw  - three-hour precipitation totals
pre1.raw  - one-hour precipitation totals
lref3.raw - layer reflectivity - layer 3
lref2.raw - layer reflectivity - layer 3
lref1.raw - layer reflectivity - layer 3
cref.raw  - composite reflectivity
bref4.raw - base reflectivity at tilt 4
bref3.raw - base reflectivity at tilt 3
bref2.raw - base reflectivity at tilt 2
bref1.raw - base reflectivity at tilt 1
brlr1.raw - 248 nm base reflectivity
srmv2.raw - storm relative radial velocity at tilt 2
srmv1.raw - storm relative radial velocity at tilt 2

So, the good news is that you will have a set of uncompressed NIDS
files to test the ARPS code on, AND if you build the ldm-mcidas
package, you will have code for a routine that converts the NIDS data
to a different format, McIDAS AREA.  This could be helpful in your
reverse engineering of the ARPS assimilation process.

re:
>Its mixed C and FORTRAN code, and I know very little of C.

The code for nids2area is a combination of Fortran and C.  The code
that reads in the NIDS file data is all in C.  I can help you wade
through this code if you like.

re: sending me the ARPS code
>If you think sending you this code can help somehow, lemme know.

It may help.  If it is a lot of code, please stick it out in a
directory I can get to on brisa.  If you are looking at one, two or
three subroutines, then send them along.

Cheers,

Tom
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* Tom Yoksas                                             UCAR Unidata Program *
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