The NARR is a reanalysis, so it don't have forecast times. I would be
simple 03 hr chain (00 hr fct time) spanning 26 years.
See an existing GDS subset aggregation:
This will give a sense for the nature of the beast.
The directory structure is set up as such:
Heres the TDS aggregation I set up while experimenting yesterday, on a
<dataset name="OceanWinds Test Daily Aggregation"
<aggregation dimName="time" type="joinNew">
<variableAgg name="wind" />
<variable name="time" orgName="time">
<attribute name="long_name" value="Days"/>
<attribute name="units" value="days since 1987-07-09" />
Would this automatically detect the source of data were GRIB rather
NetCDF? and it seems like you need to set the <scan> on each
directory... Doing so the way NARR is set up would create one chunky
configuration file. Is there anyway to have this scan a pattern
(YYYYMM/YYYYMMDD) of directories?
I understand GRIB requires a certain amount of "supplemented" metadata
for complience. Where do you enter this?
Ethan Davis wrote the following on 6/13/2006 1:21 PM:
Aggregation should work the same for GRIB as for netCDF files. The
would be how your GRIB files are structured and how you want to
aggregate them. Our GRIB files each contain one full model run (all
parameters, all forecast times). We haven't tried aggregating beyond
We have started tracking what is available for the NCEP models on our
server. This is from the TDS 3.8 announcement (with links updated):
We also are now tracking detailed inventory of NCEP model output,
These are all linked from the "collection dataset" pages; For
choose the top "CONUS_12_km" link, then choose "Available
One idea for this work is to eventually provide access to alternate
datasets, for instance, a dataset that contains all the 3hr forecast
times from the different runs, or one that contained all the 12Z valid
times from the different runs. Tracking these detailed inventories is
just the first step but aggregation and alternate groupings of the
is pretty interesting to think about.
How are your GRIB files structured and what kind of aggregation where
you thinking about?
I've been tinkering with the TDS aggregation capabilities and they
quite well for NetCDF data, however, I can't seem to find anything in
the docs regarding aggregating GRIB.
We want to get The NARR dataset which we have here at NCDC-NOMADS on
TDS. It consists of hundreds of thousands of 50 Mb + GRIB files in a
Just scouting for a quick answer here:
Is aggregating the NARR GRIB currently feasable with the current
of TDS? If so, do any docs exist which could give me a starting
Converting it to NetCDF will not be possible (volume).