[McIDAS #CKD-730239]: working with MODIS Level 2 data in McIDAS

Hi Greg,

re:
> I'm pulling some Level 2 MODIS SST products from the Oceancolor
> web site. I'd like to read these files in McIDAS and produce some
> customized sectors for the web.

> I took a look at your documentation on using the DSSERVE command
> ( http://www.unidata.ucar.edu/software/mcidas/2007/users_guide/DSSERVE.html )
> to help McIDAS recognize these files but I'm a little confused.

OK.  "For the record" the paragraph from the McIDAS Users Guide page on
DSSERVE is:

  When creating MODIS HDF image or point datasets, the file names must match
  the standard Goddard DAAC (Distributed Active Archive System) or MODIS direct
  broadcast naming conventions. In the DAAC convention, for example, 1 km Terra
  MODIS Level 1b HDF image files must follow the format 
MOD021KM.Ayyyyddd.hhmm.002.yyyyddd.hdf.
  Aqua files must begin with MYD instead of MOD, and 1/2 km and 1/4 km 
resolution
  files are denoted as HKM and QKM instead of 1KM. In the MODIS direct broadcast
  convention, for example, the same 1 km Terra image files must follow the 
format
  t1.yyddd.hhmm.1000m.hdf. Aqua files must begin with a1 instead of t1, and 1/2 
km
  and 1/4 km files are denoted as 500m and 250m instead of 1000m. Similarly, 
these
  two naming conventions can be applied to the MODIS Level 2 products in HDF 
format.

> In your example you mention that when creating MODIS image datasets a
> naming convention must be followed like so:
> 
> MOD021KM.Ayyyyddd.hhmm.002.yyyyddd.hdf for Level 1b HDF files
> 
> Do I need to rename the files I downloaded to match this convention?

I believe so, yes.  The Users Guide section on DSSERVE was written by SSEC, so I
would assume that they included the paragraph on file naming conventions because
of a need for their ADDE server.  By the way, I am a bit surprised about the
need for the disk file name to follow a rigid naming convention.  It must mean
that some information needed by the server is contained in the file name itself.

> If so, I'm not quite sure what MOD02 stands for - a data type or a
> satellite?

I assume that MOD02 is a type of data given the references to MOD06, MOD07, etc.
above the paragraph you are asking about.

> I'm also not sure what the 002 between the repeated dates
> is. Is this always the same?

I would assume that it is since the SSEC docs include it specifically.

> A sample file I downloaded has a name like:
> 
> A2008135075500.L2_LAC_SST

Was there any documentation about exactly what kind of data (other than SST)
this is?  Where did you get the data?

> BTW, I tried it without renaming but when I tried to do an IMGLIST, I
> got:
> 
> 80 ingest:/h/eol/gstoss/mcidas/data-> dsserve.k LIST
> 
> Group/Descriptor         Type  Format & Range     RT Comment
> ------------------------ ----- ------------------ -- --------------------
> GEODATA/CACHE            IMAGE AREA
>                                
> DIRFILE=/home/stoss/mcidas/data/geodata/AREA000*
> MODIS/SST                IMAGE MOD8
>                                DIRFILE=/h/eol/gstoss/mcidas/data/*L2_LAC_SST*
> MYDATA/AREAS             IMAGE AREA 1-9999           Areas in my data 
> directory
> MYDATA/GRIDS             GRID  GRID 1-9999           All gridded data in GRID 
> format
> MYDATA/IMAGES            IMAGE AREA 1-9999           All images in AREA format
> MYDATA/RTPTSRC           POINT MD   1-9999           All point source data 
> files in MD file format
> MYDATA/TOPO              IMAGE AREA 9000-9019        All topographic images 
> in AREA format
> TOPO/CONF                IMAGE AREA 9011-9011        North America (Conformal)
> dsserve.k: done

> 81 ingest:/h/eol/gstoss/mcidas/data-> imglist.k MODIS/SST.ALL
> Image file directory listing for:MODIS/SST
> imglist.k: No images satisfy the selection criteria
> imglist.k: done

Either the type of HDF data in your image is not recognized by the ADDE 
directory
server, or the server really  needs information from the file name.

> Also, your documentation mentions that McIDAS handles cloud top
> properties, atmospheric profiles, cloud masks and aerosol as well as
> SST. What about Chlorophyll A?

Quite frankly, I don't know.  If the chlorophyll data is in one of the formats
listed (e.g., MOD06, etc.), then I assume that they would be usable.  The only
way to tell for sure is by doing some experimentation.

> Thanks,

Sorry I can't be more definitive than what I provided above, but I have not 
played
around with the MODIS stuff enough to know the answers off of the top of my
head.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: CKD-730239
Department: Support McIDAS
Priority: Normal
Status: Closed