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NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
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To learn about what's going on, see About the Archive Site.
Hi Don, That is a very good question and I left that out in my response. Long term access for users in archives means we constantly have to work to fully document, understand, track down any data provenance issues, and verifying (to a lessor degree), the data. What it says it is- it actually is. Its just a form of quality assurance for users. Data providers - especially 'real time' ones don't necessarily concern themselves with these issues. They make a product- and move on. I'll bet you are fully aware that the WOC/Gateway does not even provide a complete DTG in the file name for many NWP products! I used to work w/ John Stackpole (great guy)- the original developer of Grib. He made grib as a compact communications protocol- not, as I'll also bet you are also aware, for archives. NOMADS has about 1+ petabyte to manage for users- we serviced a growing 550TB last year and we need to scale. By aggregating the data most used by users (common state variables, most popular, etc.) we can allow streaming of files/records that allows the 50K+ users and ~300 million downloads per year on NOMADS much better. Methods such as pre-staging/caching most requested data on disk from tape, etc. etc. What John is attempting to do will facilitate the access for multiple users, requesting multiple files using aggregations and other streaming caching (I don't quite understand the details there). Now- we can't even ascertain with any degree of confidence what is what- in order to even be able to aggregate- let alone feel comfortable about the accuracy of the data we are serving to users. It does not really help users find data- per se. It will help users have more confidence that a aggregated monthly mean product from CFSR is mean for each cycle (0, 6, 12, ..) for individual days of the month (the diurnals)- rather then a typical monthly mean avg'ed over the entire day. hope that makes sense. I'm not sure what other impacts this will have for us here - LAS? our TDS to ESGF capabilities? It's kinda scary, but John's radical change looks to solve a major archive problem I do know that. We will run 4.2 and 4.3 in parallel I will tell you that for some time. Best regards, Glenn On Tue, Feb 28, 2012 at 2:19 PM, Don Murray <don.murray@xxxxxxxx> wrote: > Hi Glenn- > > > On 2/28/12 11:43 AM, Glenn Rutledge wrote: > >> John and Community- >> While I do not represent the NCDC Archive, for the NCDC NOMADS systems >> and our users, I must agree that the changes John is proposing will >> facilitate the long term use of grib data. While painful to (existing) >> client (software | decoders), the proposed change will allow our users >> (with a more scalable way) to -better find and use our data. I'll >> suggest that if this is adopted, NOMADS servers could provide both 4.2 >> and 4.3 versions to (give software developers time to adapt) allow the >> client-side to adapt. >> > > Could you elaborate on how you see that the new variable names will allow > the users to better find and use your data versus the human readable names? > For example, if I want to get the 500 hPa heights from a model in your > archive, how will the new names facilitate that? > > Don > > -- > Don Murray > NOAA/ESRL/PSD and CIRES > 303-497-3596 > http://www.esrl.noaa.gov/psd/**people/don.murray/<http://www.esrl.noaa.gov/psd/people/don.murray/> > -- Glenn K. Rutledge Meteorologist/Physical Scientist NOMADS Team Leader National Climatic Data Center Asheville, NC 28801 (828) 271-4097 nomads.ncdc.noaa.gov
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