One of the NCL core developers was going to put the REMO
GRIB table which you provided into NCL's soon-to-be-released v6.2.0
but he responded as follows:
----
It is not going to be possible to support the REMO GRIB table as
long as they are putting out 0 for the center id. 0 is not a
recognized center id, so there is no valid way to identify where the
GRIB file is coming from.
----
For you, this means that you will manually have to add the
attribute information.
On 3/28/14, 8:33 AM, Mark Chan wrote:
> Dear Dennis,
>
> Thanks so so much!
> I am so moved for the kindly help. I will try to work on it following your suggestion.
>
> With my best regards,
> Mark
>
>
>
> On Friday, March 28, 2014 3:21 PM, Dennis Shea <shea@ucar.edu> wrote:
>
> [1] NCL's functions expect the hybrid coefficients to be
> of the form
>
> p = a(k)*p0 + b(k)*ps
>
> [2] The REMO coefficients which you sent as an ascii file are
> of the form
>
> p = ap(k) + b(k)*ps
>
> where ap(k) => =a(k)*p0
>
> Hence, to use NCL's functions you must convert. This is trivial.
>
> ; Read hybrid coefficients; make REMO coefficients like CAM coefficients
>
> dir_coef = "./"
> fil_coef = "REMO2.coeficients"
> coef = readAsciiTable(dir_coef+fil_coef, 3, "float", 2)
> hyam = coef(:,1)
> hybm = coef(:,2)
>
> P0 = 100000. ; make like CAM
> hyam = hyam/P0
>
> print("---")
> print(sprintf("%9.6f", hyam)+" "+sprintf("%9.6f", hybm))
>
> [3] The REMO GRIB tables are not fully contained with NCL's
> built-in suite of GRIB lookup tables.
>
> Complete info on NCL's GRIB is at:
>
> http://www.ncl.ucar.edu/Document/Manuals/Ref_Manual/NclFormatSupport.shtml#GRIB
>
> This can be a bit overwhelming so no need to read it.
>
> However, the section: "User-defined GRIB1 parameter tables"
>
> would allow you to input the appropriate GRIB table form
> expected by NCL. The table you sent would have to be reformatted.
>
> The attached added the meta data.
>
> It creates a netCDF file.
>
> Good luck
>
>
>
> On 3/21/14, 8:53 PM, Dennis Shea wrote:
>> The file contains no hybrid coefficients. It contains
>> numbers for each hybrid level. These are useless for
>> interpolation to constant ressure levels..
>>
>> ncl-talk has no REMO files available to examine.
>> If you send a REMO files (grib or netCDF) include
>> another file with the actualy hybrid coefficients on it.
>>
>> ---
>>
>> ftp ftp.cgd.ucar.edu
>> anonymous
>> email
>> cd incoming
>> put REMO.{grb,nc}
>> put REMO_hybrid,{grb,nc}
>> quit
>>
>> Then send email to ncl-talk@ucar.edu stating the names
>> of the files. Please do not reply or cc me.
>>
>> Cheers
>>
>>
>> On 3/21/14, 3:41 PM, Mark Chan wrote:
>>> Dear NCL users,
>>>
>>> From the link below I found an example for interpolation from hybrid coordinates to pressure levels, but as it said that it only works for CSM data. I have REMO data and wonder how to do the interpolation. Expecially I am not sure how to define variables such as "PS", "hyam", "hybm" as shown in the below:
>>> T = in->T ; select variable to ave
>>> P0mb =1000.
>>> hyam = in->hyam ; get a coefficiants
>>> hybm = in->hybm ; get b coefficiants
>>> PS = in->PS ; get pressure
>>> https://www.ncl.ucar.edu/Applications/Scripts/vert_1.ncl
>>>
>>>
>>> ---my data info from ncdump is as:------------
>>>
>>> netcdf CC_var131 {
>>> dimensions:
>>> initial_time0_hours = 21 ;
>>> lv_HYBY1 = 27 ;
>>> g0_lat_2 = 300 ;
>>> g0_lon_3 = 400 ;
>>> ncl_strlen_0 = 18 ;
>>> variables:
>>> float VAR_131_GDS0_HYBY(initial_time0_hours, lv_HYBY1, g0_lat_2, g0_lon_3) ;
>>> VAR_131_GDS0_HYBY:forecast_time_units = "hours" ;
>>> VAR_131_GDS0_HYBY:forecast_time = 0 ;
>>> VAR_131_GDS0_HYBY:parameter_number = 131 ;
>>> VAR_131_GDS0_HYBY:parameter_table_version = 128 ;
>>> VAR_131_GDS0_HYBY:gds_grid_type = 0 ;
>>> VAR_131_GDS0_HYBY:level_indicator = 110 ;
>>> VAR_131_GDS0_HYBY:_FillValue = 1.e+20f ;
>>> VAR_131_GDS0_HYBY:units = "unknown" ;
>>> VAR_131_GDS0_HYBY:long_name = "Unknown Variable Name" ;
>>> double initial_time0_hours(initial_time0_hours) ;
>>> initial_time0_hours:units = "hours since 1800-01-01 00:00" ;
>>> initial_time0_hours:long_name = "initial time" ;
>>> double initial_time0_encoded(initial_time0_hours) ;
>>> initial_time0_encoded:units = "yyyymmddhh.hh_frac" ;
>>> initial_time0_encoded:long_name = "initial time encoded as double" ;
>>> float g0_lat_2(g0_lat_2) ;
>>> g0_lat_2:La1 = 28.f ;
>>> g0_lat_2:Lo1 = -10.f ;
>>> g0_lat_2:La2 = 60.89f ;
>>> g0_lat_2:Lo2 = 33.89f ;
>>> g0_lat_2:Di = 0.11f ;
>>> g0_lat_2:Dj = 0.11f ;
>>> g0_lat_2:units = "degrees_north" ;
>>> g0_lat_2:GridType = "Cylindrical Equidistant Projection Grid" ;
>>> g0_lat_2:long_name = "latitude" ;
>>> float g0_lon_3(g0_lon_3) ;
>>> g0_lon_3:La1 = 28.f ;
>>> g0_lon_3:Lo1 = -10.f ;
>>> g0_lon_3:La2 = 60.89f ;
>>> g0_lon_3:Lo2 = 33.89f ;
>>> g0_lon_3:Di = 0.11f ;
>>> g0_lon_3:Dj = 0.11f ;
>>> g0_lon_3:units = "degrees_east" ;
>>> g0_lon_3:GridType = "Cylindrical Equidistant Projection Grid" ;
>>> g0_lon_3:long_name = "longitude" ;
>>> int lv_HYBY1_l1(lv_HYBY1) ;
>>> lv_HYBY1_l1:units = "number" ;
>>> lv_HYBY1_l1:long_name = "layer between two hybrid levels" ;
>>> int lv_HYBY1_l0(lv_HYBY1) ;
>>> lv_HYBY1_l0:units = "number" ;
>>> lv_HYBY1_l0:long_name = "layer between two hybrid levels" ;
>>> char initial_time0(initial_time0_hours, ncl_strlen_0) ;
>>> initial_time0:NCL_converted_from_type = "string" ;
>>> initial_time0:units = "mm/dd/yyyy (hh:mm)" ;
>>> initial_time0:long_name = "Initial time of first record" ;
>>> // global attributes:
>>> :creation_date = "Fri Mar 21 16:00:34 CET 2014" ;
>>> :NCL_Version = "6.1.2" ;
>>> :system = "Linux hexagon-1 2.6.32.59-0.7.1_1.0402.7200-cray_gem_s #1 SMP Wed May 1 03:59:09 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux" ;
>>> :Conventions = "None" ;
>>> :grib_source = "CC_var131.grb" ;
>>> :title = "NCL: convert-GRIB-to-netCDF" ;
>>>
>>>
>>> Thanks so much in advance!
>>> Mark
>>>
>>>
>>>
>>> _______________________________________________
>>> ncl-talk mailing list
>>> List instructions, subscriber options, unsubscribe:
>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
>>>
>> _______________________________________________
>> ncl-talk mailing list
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>
_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Fri Mar 28 11:53:08 2014
This archive was generated by hypermail 2.1.8 : Mon Mar 31 2014 - 11:47:09 MDT