Re: CloudSat and NCL

THX for ftping the file

The conversion works fine with the most recent version of NCL (6.1.2).
Please download that version.

===

%> ncl_convert2nc 2007001005141_03607_CS_2B-GEOPROF_GRANULE_P_R04_E02.hdf

Further,

%> ncl_filedump 2007001005141_03607_CS_2B-GEOPROF_GRANULE_P_R04_E02.hdf

yields the fact that this is an HDF-EOS file.

Variable: f
Type: file
filename: 2007001005141_03607_CS_2B-GEOPROF_GRANULE_P_R04_E02
path: 2007001005141_03607_CS_2B-GEOPROF_GRANULE_P_R04_E02.hdf
    file global attributes:
       HDFEOSVersion : HDFEOS_V2.5 <*********************** NOTE
       StructMetadata_0 : GROUP=SwathStructure

[SNIP-----SNIP]

       granule_number : 3607
       ID_SITE : Cooperative Institute for Research in the Atmosphere
       ID_CENTER : CloudSat Data Processing Center
       ID_CENTER_URL : http://cloudsat.cira.colostate.edu
       ID_MACHINE : SKINKO
       ID_CREATED : Wed Jul 18 09:25:40 2007
       algorithm_version : 5.3
       product_version : 011
       start_time : 20070101005141
       end_time : 20070101023034
    dimensions:
       nray_2B_GEOPROF = 37081
       nbin_2B_GEOPROF = 125
    variables:
       short Height ( nray_2B_GEOPROF, nbin_2B_GEOPROF )
          _FillValue : -9999
          factor : 1
          offset : 0
          long_name : Height of range bin in Reflectivity/Cloud Mask
above reference surface (~ mean sea level).
          units : m
          valid_range : ( -5000, 30000 )
          missing : -9999
          missop : ==
          hdf_name : Height

       byte CPR_Cloud_mask ( nray_2B_GEOPROF, nbin_2B_GEOPROF )
          _FillValue : -99
          factor : 1
          offset : 0
          long_name : CPR Cloud Mask
          valid_range : ( 0, 40 )
          missing : -9
          missop : ==
          hdf_name : CPR_Cloud_mask

       short Gaseous_Attenuation ( nray_2B_GEOPROF, nbin_2B_GEOPROF )
          _FillValue : 15360
          factor : 100
          offset : 0
          long_name : Gaseous_Attenuation
          units : dBZe
          valid_range : ( 0, 1000 )
          missing : -9999
          missop : ==
          hdf_name : Gaseous_Attenuation

       short Radar_Reflectivity ( nray_2B_GEOPROF, nbin_2B_GEOPROF )
          _FillValue : 15360
          factor : 100
          offset : 0
          long_name : Radar Reflectivity Factor
          units : dBZe
          valid_range : ( -4000, 5000 )
          missing : -8888
          missop : ==
          hdf_name : Radar_Reflectivity

===================================================

Unfortunately, this means that you will likely need to read
the file twice. Once with the hdf extension and a 2nd time with
the .hdfeos extension to get all the informtion (eg, latitudes and
longitudes

     fhdf = addfile("2007001005141...hdf","r")
     feos = addfile("2007001005141...hdf.hdfeos","r")

Then access the data as required.

===

After you download 6.1.2, try

%> ncl_filedump
2007001005141_03607_CS_2B-GEOPROF_GRANULE_P_R04_E02.hdf.hdfeos

you will note different look includin the lat/lon arrays.

[snip]
       float Longitude_2B_GEOPROF ( nray_2B_GEOPROF )
          long_name : longitude
          units : degrees_east
          hdfeos_name : Longitude

       float Latitude_2B_GEOPROF ( nray_2B_GEOPROF )
          long_name : latitude
          units : degrees_north
          hdfeos_name : Latitude

On 7/23/13 8:14 AM, Dennis Shea wrote:
> [1] ncl_convert2nc should work. PLease ftp the file so it
> can be examined.
>
> ftp ftp.cgd.ucar.edu
> anonymous
> email
> cd incoming
> put 2007001005141_03607_CS_2B-GEOPROF_GRANULE_P_R04_E02.hdf
> quit
>
> [2] There is no functuon
> p = f(geometric_height)
>
> [a] If you have the appropriate information (z0, p0) and
> geopotential height is useful, use the hydrostatic equation
>
> p = p0*exp(-g*(z-z0)/(R*T))
>
> where z0 and p0 are the reference levels.
> This could be done via array notation.
>
> [b]
> http://www.ncl.ucar.edu/Document/Functions/Built-in/stdatmus_z2tdp.shtml
>
> could also be used.
>
> On 7/23/13 7:53 AM, Marston Johnston wrote:
>> Hi,
>>
>> I'm trying to use NCL to bin CloudSat granules from 2007 and 2008. I'll be
>> using the bin_sum function and modifying the example given in
>>
>> http://www.ncl.ucar.edu/Applications/Scripts/cloudsat_1.ncl.
>> I have a few things I'd like to ask:
>>
>> 1.) I tried to convert the HDF files to netcdf, since I work mostly with
>> netcdf files, but ncl_convert2nc failed to convert the files. I'm using NCL
>> version 6.1.0. According to
>> http://www.ncl.ucar.edu/Document/Tools/ncl_convert2nc.shtml, this function
>> should be able to convert CloudSat files. The error I got is:
>>
>> *********
>> ncl_convert2nc 2007001005141_03607_CS_2B-GEOPROF_GRANULE_P_R04_E02.hdf
>> fatal:syntax error: line 1 before or near 2007001005141
>> ncl_convert2nc 2007001005141
>> ---------------------------^
>>
>> fatal:error in statement
>> *********
>>
>> Ok, I can use ncl to read the hdd 4 data instead of converting first and
>> this should be ok. But I'm curious as to why the conversion failed. Did I
>> misunderstand the docs for NCL?
>>
>> 2.) The data is expressed on geometric height and I would like to express
>> it on pressure levels instead. The temperature with in each profile is
>> available in the granules. Can NCL do this? I did a quick search in the
>> function list but to no avail.
>>
>> Appreciate the help,
>> /M
>>
>>
>>
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Received on Tue Jul 23 09:13:56 2013