[ncl-talk] ARL gdas0p5 data handling

[HAVENER, KEVIN F GS-12 USAF ACC 14 WS/WXED]

John,

I looked at the files, but darned if I can figure out what the HYSPLIT-compatible format is they speak of on that site.  However, I do recognize the data type.  It is the same data as can be found in grib2 format at http://rda.ucar.edu.  Datasets 093.0 (1979-2010) and 094.0 (2011 to present) in particular.  In DS 093.0 it is known gdas and in the the later set it is cdas1, but it is the same data.  It looks like ARL creates a dataset from the Global Data Assimilation System (GDAS).  Well, so does the Climate Forecast System Reanalysis (versions 1 and 2, aka DS 093.0 and 094.0).  The RDA dataset is complete, higher time resolution, and has the same spatial resolution (0.5-degree) as the ARL data.  One possible difference is that the ARL set uses the hybrid sigma vertical coordinate system, and RDA uses pressure vertical coordinate system.  I can't remember if the data is also available using the hybrid sigma coordinate system or not--I don't use it.  If you can't make the ARL data set work for your needs, I would suggest looking into the RDA version of the data to see if it will suffice.  Side note:  I manipulate the RDA data set with wgrib2 and convert to netcdf all the time.  It just works. 

Kevin Havener


-----Original Message-----
From: ncl-talk-bounces at ucar.edu [mailto:ncl-talk-bounces at ucar.edu] On Behalf Of Hyun, John
Sent: Tuesday, April 28, 2015 7:04 AM
To: ncl-talk at ucar.edu
Subject: [ncl-talk] ARL gdas0p5 data handling

Dear all,

Is there anyone have some experience for ARL(NOAA Air Resources Laboratory) gdas0p5 data handling with NCL ?

I am trying to read gdas0p5 data which we can download from ftp://ftp.arl.noaa.gov/archives/gdas0p5 site.

But I don't have any information about this data format, if anyone have some code for this data, please share with me.


-- 

John Hyun