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Ethan: The NARR is a reanalysis, so it don't have forecast times. I would be a simple 03 hr chain (00 hr fct time) spanning 26 years. See an existing GDS subset aggregation: http://nomads.ncdc.noaa.gov:9091/dods/NCEP_NARR_DAILY/narr-a_221_tmpprs.subset.info This will give a sense for the nature of the beast. The directory structure is set up as such: http://nomads.ncdc.noaa.gov/data/narr/ Heres the TDS aggregation I set up while experimenting yesterday, on a non-related dataset: <dataset name="OceanWinds Test Daily Aggregation" ID="test/dailyagg" urlPath="test/agg"> <serviceName>allTest</serviceName> <netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2"> <aggregation dimName="time" type="joinNew"> <variableAgg name="wind" /> <scan dateFormatMark="#yyyyMMdd" location="/eclipse1a/ftp/pub/seawinds/SI/daily/netcdf/1980s/" suffix=".nc" /> <scan dateFormatMark="#yyyyMMdd" location="/eclipse1a/ftp/pub/seawinds/SI/daily/netcdf/1990s/" suffix=".nc" /> <scan dateFormatMark="#yyyyMMdd" location="/eclipse1a/ftp/pub/seawinds/SI/daily/netcdf/2000s/" suffix=".nc" /> </aggregation> <variable name="time" orgName="time"> <attribute name="long_name" value="Days"/> <attribute name="units" value="days since 1987-07-09" /> </variable> </netcdf> </dataset> Would this automatically detect the source of data were GRIB rather than NetCDF? and it seems like you need to set the <scan> on each individual 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? -Dan Ethan Davis wrote the following on 6/13/2006 1:21 PM: > Hi Dan, > > Aggregation should work the same for GRIB as for netCDF files. The issue > 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 that. > > 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, eg: > > http://motherlode.ucar.edu:8080/thredds/modelInventory/model/NCEP/NAM/CONUS_12km/ > > These are all linked from the "collection dataset" pages; For > example from > > http://motherlode.ucar.edu:8080/thredds/catalog/model/NCEP/NAM/CONUS_12km/catalog.html > > choose the top "CONUS_12_km" link, then choose "Available Inventory" > Documentation. > > 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 data > is pretty interesting to think about. > > How are your GRIB files structured and what kind of aggregation where > you thinking about? > > Ethan > > dan.swank wrote: > >> Hello, >> >> I've been tinkering with the TDS aggregation capabilities and they work >> 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 the >> TDS. It consists of hundreds of thousands of 50 Mb + GRIB files in a >> YYYYMM/YYYYMMDD tree. >> Just scouting for a quick answer here: >> Is aggregating the NARR GRIB currently feasable with the current release >> of TDS? If so, do any docs exist which could give me a starting point? >> Converting it to NetCDF will not be possible (volume). >> >> > > -- Dan Swank <address@hidden> NOMADS Project: Software & Data Management Contractor - STG, Incorporated Veach-Baley Federal Building 151 Patton Avenue Asheville, NC 28801-5001 Phone: 828-271-4007 =============================================================================== To unsubscribe thredds, visit: http://www.unidata.ucar.edu/mailing-list-delete-form.html ===============================================================================