Hi John,
Defining terms should be sufficient; terminology is not consistent from
my experience. At some point people my want to extend the basic
terminology. Here is a start:
hindcast - re-creation of past fields using collected observations in
boundary conditions
nowcast - short time-period prediction of near-real-time fields using
real-time data
forecast - prediction of future fields beyond influence of real-time data
-CJ
John Caron wrote:
> Hi CJ:
>
> At the moment, the nj22 library needs to identify the
> forecast_reference_time and time coordinates. At the higher "Grid
> Datatype" layer, we calculate "forecast offsets" (time - reference),
> in which case hindcasts have negetive offsets, nowcasts have offset 0,
> and forecasts have positive offsets. In this sense, the only thing we
> really need from CF metadata is forecast_reference_time and time. Do
> you think it would be sufficient to annotate the spec to clarify the
> meaning of hindcast, nowcast and forecast times?
>
> CJ Beegle-Krause wrote:
>
>> There is a need to distinguish whole or parts of model runs, for
>> example hindcast, nowcast and forecast could be sections of the same
>> individual model run. It would also be good to agree on what each of
>> those terms could mean.
>>
>> John Caron wrote:
>>
>>> another one is "forecast_reference_time", the base time a model run
>>> was made from.
>>>
>>> Ed Hartnett wrote:
>>>
>>>> Howdy all!
>>>>
>>>> The CF document says that standard_name may be used for time
>>>> coordinate variables.
>>>>
>>>> But the standard name table gives only one valid standard_name for a
>>>> time variable: "time".
>>>>
>>>> Can I assume then that there are no other standard names for time
>>>> coordinate variables?
>>>>
>>>> Thanks!
>>>>
>>>> Ed
>>>>
>>> _______________________________________________
>>> CF-metadata mailing list
>>> CF-metadata at cgd.ucar.edu
>>> http://www.cgd.ucar.edu/mailman/listinfo/cf-metadata
>>
>>
>>
>>
>> --
>> CJ Beegle-Krause, Ph.D.
>> NOAA/NOS/ORR/Hazmat
>> 7600 Sand Point Way NE
>> Seattle, WA 98115
>> voice: (206) 526-6961
>> fax: (206) 526-6329
>>
>> <:}}}}}><
>> <:}}}}}><
>>
>> \!/ \!/ \!/ >^<**>^< \!/ \!/ \!/
>>
>>
>> ------------------------------------------------------------------------
>>
>> _______________________________________________
>> CF-metadata mailing list
>> CF-metadata at cgd.ucar.edu
>> http://www.cgd.ucar.edu/mailman/listinfo/cf-metadata
>
> _______________________________________________
> CF-metadata mailing list
> CF-metadata at cgd.ucar.edu
> http://www.cgd.ucar.edu/mailman/listinfo/cf-metadata
--
CJ Beegle-Krause, Ph.D.
NOAA/NOS/ORR/Hazmat
7600 Sand Point Way NE
Seattle, WA 98115
voice: (206) 526-6961
fax: (206) 526-6329
<:}}}}}><
<:}}}}}><
\!/ \!/ \!/ >^<**>^< \!/ \!/ \!/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.cgd.ucar.edu/pipermail/cf-metadata/attachments/20061005/ed638a60/attachment-0002.html>
Received on Thu Oct 05 2006 - 07:01:57 BST
