[Go-essp-tech] [metafor] the CMIP5 file uri structure

Tue Feb 17 02:10:10 MST 2009

Hi Bryan,

If you want an example of decadal forecasts as we have carried out in 
ENSEMBLES, please let me know and I'll send you a CF-compliant NetCDF 
file and the THREDDS link for further exploration.

Best regards,
Paco

Bryan Lawrence wrote:
> Hi Paco
> 
> Thanks for this.
> 
> I think the two times (time instant and period) do correspond
> with CF as you suggest.
> 
> You've got me worried about a couple of things on the time front though,
> I had thought the decadal runs would essentially be different experiments
> but you're right, the delineation might not be so clean. We'll make sure
> we explicity put an example or two in the doc for the decadal runs so that we're sure
> we have it right.
> 
> Cheers
> Bryan
> 
> 
> On Tuesday 17 February 2009 07:33:18 Francisco J. Doblas-Reyes wrote:
>> Dear Bryan,
>>
>> After having a look at the message below that you sent to the Metafor 
>> community, I was wondering whether the DRS should apply to both types of 
>> CMIP5 simulations: climate-change projections and decadal predictions. 
>> If it applies, are the components "time instant" and "period" enough to 
>> describe decadal forecasts that overlap in time? Are they equivalent to 
>> the CF coordinates "forecast_reference_time" and "forecast_period"? For 
>> the decadal forecasts in ENSEMBLES, we needed two axes to describe the 
>> decadal forecasts in NetCDF. In GRIB we didn't have a problem because 
>> ECMWF extensions already have to axes.
>>
>> Regards,
>> Paco
>>
>>
>> Bryan Lawrence wrote:
>>> hi Folks
>>>
>>> See attached email which has the current state of play, and the attached doc.
>>> It's not obvious to me who makes the decision that this is *THE* CMIP structure.
>>> It yet needs linking to the proposed netcdf attributes.
>>>
>>> Cheers,
>>> Bryan
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> Subject:
>>> Re: uniform URL syntax to support CMIP5/AR5
>>> From:
>>> Bryan Lawrence <bryan.lawrence at stfc.ac.uk>
>>> Date:
>>> Tue, 10 Feb 2009 15:28:27 +0000
>>> To:
>>> Steve Hankin <Steven.C.Hankin at noaa.gov>
>>>
>>> To:
>>> Steve Hankin <Steven.C.Hankin at noaa.gov>
>>> CC:
>>> Bryan Lawrence <b.n.lawrence at rl.ac.uk>, Michael Lautenschlager 
>>> <lautenschlager at dkrz.de>, "V. Balaji" <V.Balaji at noaa.gov>, Don Middleton 
>>> <don at ucar.edu>, Cinquini Luca <luca at ucar.edu>, "Dean N. Williams" 
>>> <williams13 at llnl.gov>, "Karl E.Taylor" <taylor13 at llnl.gov>, 
>>> charlotte.pascoe at rl.ac.uk
>>>
>>>
>>> Hi Guys
>>>
>>> I've made a couple of minor changes and comments.
>>>
>>> 1): this is primarily about CMIP5 ... not AR5 ... so the nomenclature should reflect that. (I've fixed that throughout I think).
>>>
>>> 2): Karl has already been working on some aspects of internal netcdf file vocabs, model short names etc, which should
>>> match these ...  we should make sure these are all congruent with the file convention. Someone needs to take responsibility for this. I suggest that Charlotte do that ... (which consists mainly of downloading Karl's input into this doc).
>>>
>>> 3): I think the hostname part of the path should be out of scope. We would expect multiple copies of atomic
>>> datsets to be held within the federation. 
>>>
>>> 4) The definition of an atomic dataset doesn't allow for the different periods within the same run being different atomic datasets (although the syntax does). I didn't fix that.
>>>
>>> Cheers
>>> Bryan
>>>
>>>
>>>
>>> On Friday 06 February 2009 16:41:51 Steve Hankin wrote:
>>>> Gents,
>>>>
>>>> In October 2007, when we met at GFDL for AR5/CMIP5 data management 
>>>> planning, we agreed on the need for a shared URL syntax.  The idea was 
>>>> that the URL would uniformly reference data holdings, regardless of 
>>>> where they were located.  A draft of that document has been circulated 
>>>> several times -- most recently at the GO-ESSP meeting in Seattle this 
>>>> past September.  Based upon recent discussions Martin and I have  
>>>> expanded the document (just a little) to encompass the encoding of time 
>>>> periods as part of the syntax.  I have attached what I hope is the 
>>>> semi-final (?) version of that document (v0.10) here.
>>>>
>>>> I suspect we need to take two steps to proceed from this point:
>>>>
>>>>    1. To suggest final changes (if any) and then to mutually endorse (if
>>>>       still agreed) the use of this URL as a means to reference data
>>>>       through *whatever* access mechanisms (OPeNDAP, WCS, FTP, ...)
>>>>    2. To make implementation plans for specific systems (and for DNS
>>>>       mapping as we see appropriate)
>>>>
>>>> Open for discussion ...
>>>>
>>>>     - Steve
>>>>
>>>
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> _______________________________________________
>>> metafor mailing list
>>> metafor at lists.enes.org
>>> https://lists.enes.org/mailman/listinfo/metafor
> 
> 
> 

-- 
________________________________________

Francisco J. Doblas-Reyes
European Centre for Medium-Range
Weather Forecasts (ECMWF)
Shinfield Park, RG2 9AX
Reading, UK

Tel: +44 (0)118 9499 655
Fax: +44 (0)118 9869 450
f.doblas-reyes at ecmwf.int
_______________________________________