Re: [thredds] Question about NARR-A Monthly Complete PoR Aggregation NetcdfSubset

  • To: Dan Swank <dan.swank@xxxxxxxx>
  • Subject: Re: [thredds] Question about NARR-A Monthly Complete PoR Aggregation NetcdfSubset
  • From: Glenn Rutledge <glenn.rutledge@xxxxxxxx>
  • Date: Wed, 16 Nov 2011 15:52:53 -0500
Cedric,
Sorry all to post to TDS list but need to ensue this errata is posted to
those that saw the below,
.....the veggie type is not static, the vegetation faction comes from a
monthly climatology which is interpolated to actual day of month at each
gridpoint.

I am still gathering an answer from NCEP on your question about temp/ht
above gnd computations for the NARR.
This tread, is now off THREDDS :)
Glenn

On Tue, Nov 15, 2011 at 3:42 PM, Dan Swank <dan.swank@xxxxxxxx> wrote:

> This aggregation is nothing more than a TDS software aggregation
>    of the narrmon-a_221_*  files.
> The Vegetation Type parameter is a static fixed field:
>
> http://nomads.ncdc.noaa.gov/thredds/catalog/narr/catalog.html?dataset=narr/AWIP32-fixed.grb
> I do not know why it would even appear in the narrmon-a files.
> ALL fields in the narrmon fields and files are averages of the
> <days_in_month>*8
>     fields in that month.  Even for fields where avg() doesn't make sense,
>     such as precipitation rate or anything with time in the denominator of
> the unit
>     - which are typically more useful as a sum() statistical operation.
>
>           -Dan
>
>
> On Tue, Nov 15, 2011 at 2:08 PM, Glenn Rutledge 
> <glenn.rutledge@xxxxxxxx>wrote:
>
>> Hello Cedric,
>> Myself or one of the NOMADS Team will reply to your questions soon- were
>> looking into it.
>> Glenn- @ NOMADS
>>
>> On Thu, Nov 10, 2011 at 12:00 PM, Cédric David <
>> cedric.david@xxxxxxxxxxxxxxx> wrote:
>>
>>> Dear THREDDS user group,****
>>>
>>> I’m unsure whether or not this is the right place to send these
>>> questions.  If not, I’d love some advice on who to direct them to.****
>>>
>>> I’ve been getting North American Regional Reanalysis (NARR) data from
>>> http://nomads.ncdc.noaa.gov/thredds/narr.html using the netCDFSubset
>>> tool.  I am running some analysis on these netCDF files with focus on
>>> Precipitation, Evaporation, Runoff, Vegetation and Surface Air
>>> Temperature.  I have therefore downloaded the following variables:****
>>>
>>> **·         **Evaporation (time, y, x)****
>>>
>>> **·         **Subsurface_runoff_baseflow (time, y, x) ****
>>>
>>> **·         **Surface_runoff_non-infiltrating (time, y, x) ****
>>>
>>> **·         **Total_precipitation (time, y, x)****
>>>
>>> **·         **Vegetation  (time1, y, x)****
>>>
>>> **·         **Temperature_height_above_ground (time1,
>>> height_above_ground, y, x)****
>>>
>>> ** **
>>>
>>> I’m interested in a 20-year average of these fields (from
>>> 1980-01-01-0000 to 2000-12-31-2100) so I figured I’d use the “NARR-A
>>> Monthly Complete PoR Aggregation” and download monthly averages in one
>>> unique file which I’d then use to compute a 20-year average.  The process
>>> ran fine but I’m curious about the netCDF file that I was able to
>>> download.  The first four variables (Evaporation,
>>> Subsurface_runoff_baseflow, Surface_runoff_non-infiltrating and
>>> Total_precipitation) indeed have several monthly grids.  However the last
>>> two variables (Vegetation and Temperature_height_above_ground) only have
>>> one unique grid each.  ****
>>>
>>> ** **
>>>
>>> So I downloaded several 3-hourly NARR-A files from the NetcdfSubset tool
>>> that I picked randomly from the entire dataset:****
>>>
>>> **·         **narr-a_221_19790101_0000_000.grb.nc ****
>>>
>>> **·         **narr-a_221_19800101_0000_000.grb.nc****
>>>
>>> **·         **narr-a_221_20001231_2100_000.grb.nc****
>>>
>>> **·         **narr-a_221_20100101_0000_000.grb.nc****
>>>
>>> **·         **narr-a_221_20111031_2100_000.grb.nc****
>>>
>>> ** **
>>>
>>> I realized that the Vegetation variable had the same exact grid for all
>>> these files.  So it makes sense to only have one grid in the aggregation.
>>> However, the Temperature_height_above_ground grid varies with time.****
>>>
>>> ** **
>>>
>>> So here are my two questions:****
>>>
>>> **1)      **Is the NARR Vegetation variable static?****
>>>
>>> **2)      **How is the Temperature_height_above_ground grid in the
>>> NARR-A Monthly Complete PoR Aggregation computed?****
>>>
>>> ** **
>>>
>>> Any help and advice would be greatly appreciated!!!****
>>>
>>> Many thanks,****
>>>
>>> Cedric ****
>>>
>>>  _______________________________________________
>>> thredds mailing list
>>> thredds@xxxxxxxxxxxxxxxx
>>> For list information or to unsubscribe,  visit:
>>> http://www.unidata.ucar.edu/mailing_lists/
>>>
>>
>>
>> _______________________________________________
>> thredds mailing list
>> thredds@xxxxxxxxxxxxxxxx
>> For list information or to unsubscribe,  visit:
>> http://www.unidata.ucar.edu/mailing_lists/
>>
>
>
>
> --
> =======================================
> Dan Swank
> STG, Incorporated - Government Contractor
> NCDC-NOMADS Project:  Software & Data Management
> Data Access Branch
> National Climatic Data Center
> Veach-Baley Federal Building
> 151 Patton Avenue
> Asheville, NC 28801-5001
> Email: Dan.Swank@xxxxxxxx
> Phone: 828-271-4007
> =======================================
>
>
  • 2011 messages navigation, sorted by:
    1. Thread
    2. Subject
    3. Author
    4. Date
    5. ↑ Table Of Contents
  • Search the thredds archives: