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NOAA Operational Model Archive and Distribution System Distribution of Real-Time and Retrospective NCEP Model Data Sets RT-NOMADS Jordan C. Alpert email@example.com Jun Wang firstname.lastname@example.orgAlpert 6/5/03 where the nation’s climate and weather services begin
NOMADS is an agreement between agencies who participate to have common … • Data and observation distribution software, format independent and description methodology, • Documentation and organization framework, • Forum to plan and organize • Funding avenue to direct $. … for university, federal agencies and organizations, a mechanism to obtain support for the dissemination of their data sets.
Participants U.S.- NOAA, DOE, NASA, NCAR, Unidata, COLA, OPeNDAP Project, & Several Universities International- CEOS NERC ESG UK BADC BOM / Dept. of State via CAP
NOMADS and the NCEP Real Time Component A solution for Recommendation 5 of “Fair Weather: Effective Partnership in Weather and Climate Services” • Wider information dissemination through web pages and other avenues. • Framework to create specialized and value added products needs access to weather data. • Facilitate communication among commercial, public, research community and federal agencies. • NOMADS is a system for participants to interact with others using common protocols and formats. Existing differences in details are mollified by software.
RT-NOMADS at NCEP Consists of • Distributed Ocean Data Server - OPEN_DAP (DODS) based on metadata file descriptors and XML. • Web based ftp, the NCEP ftp2u client and “Great Displays” (pdisp), a grid analysis and display client. • Model initialization ingredients, “The minimum set” for model rerun/retrospective analysis ready observations & restart files. • The Real Time NCEP Operational model run history.
RT-NOMADS is a service for science, development and public access. To distribute NCEP’s Operational data set to researchers and the public. To provide server software to NOAA projects who need to serve their data through web services. • NCEP NOMADS servers are the intermediary between NCEP operational computers and NCDC NOMADS archive servers.
Tools for Users on the server • Pare down large file sizes of high resolution initialization and model results. • (re-) Group different data sets to create needed products – such as initialization files for model development. • Subset the data sets in parameter space • Subset the data sets in physical space (subset the grid in 4 dimensions)
NCEP Real-Time Server • Real time. • Operational Suite of Model products. • Forecast information for model comparison. • Operational initialization and observations. • Maintenance of codes, utilities for data manipulation and grid transformation, sub-setting • Documentation. • Serves as transfer point to NCDC for NOMADS archive of reruns and retrospectives.
The Server – Client distributed relationship:A Common Sense Approach to Data Distribution Examples of Clients : • ftp2u, Great Displays, and GDS allow sub-setting of data by parameter, by 3D region, and by time. • Allows for results with low band width! Eg., NASA/GSFC takes 1 hour to ftp entire GFS (AVN) forecasts or 13 seconds to download their desired fields (ftp2u). • GDS: NOMADS participants serve up their data sets through a client-server relationship, that is, the data sets are internet ready and the display is done by the client.
Extending NOMADS to Real Time • The A in NOMADS is for Archive. • NCEP historical cases for rerun/retrospective ocean, atmosphere and climate. • NCEP Real Time model output in the NOMADS framework … so there is a seamless access to these important data sets at NCEP and at NCDC! RT-NOMADS provides the framework for long term support to be available to keep up with modeling advances.
RT-NOMADS is a prototype Goals: • Provide proof of the concept that distributed systems can serve data sets across agencies. • Specify an Operational system for NOAA/TOC, • Provide current state of the art capability and move more complete data sets, • Use benchmarks to characterize system loads in order to determine costs and give NOAA administration the information it needs to triage data resources.
… GrADS client …. commands Sdfopen http://nomad2:9090/dods/reanalysis-2/pgb/hgt t = 1 'set gxout shaded' while (t <= 1068) 'set t 't 'q time' date=subwrd(result,3) 'draw title hgtprs 'date' 't 'd hgtprs' '/home/wd23ja/grads/lib/cbarn.gs' 'swap' t = t + 1 endwhile
Getting data without GrADS or a commercial client: http://184.108.40.206:9090/dods/eta/eta20030527/eta_00z.ascii?tmpprs[0:0][0:0][30:130] [290:290] #the order of the square bracked values is: # [time][level][lat][lon] # where lat is measured from the south pole (0) # to equator (90) to NP (180) (Use a “wget” and the URL with the ascii response in cron or a cgi-bin script provides the needed number(s) when and where needed.)
NOMADS clients at NCEP “Great Displays” (pdisp) and ftp2u by Ebisuzaki and modified by Wang • Real Time Operational model data sets from GFS, and ETA from present to one month ago. • Attention to accumulation variable differences and high and low resolution. • Analysis pgb, restart files. • Recent (“real time”) climate runs, ie., RSM. • Observations (soon). • Reanalysis-2 (and 1) • AMIP type runs (Suru’s finest runs eg., 28 and 64 levels 1978-2002), sudden warming, ….
MATLAB: A Commerical Client server=‘nomad2:9090’; directory=‘/dods/gdas/rotating/’; fext=‘ascii’; model=‘gdas’; datestr=‘YYYYMMDDHH’; varname=‘hgt’; varlevs=‘1’; Arrc=[‘[‘,t1,’:’,t2,’][‘,nlev1,’:’,nlev2,’][‘,ilat1,’:’,ilat2,’][‘,ilon1,’:’,ilon2,’]’]; urlstring=[http://’,server,directory,model,datestr,’.’,fext,’?’,varname,arrc]; url = java.net.URL(urlstring); % connect to web page Try stream = openStream(url) ireader = java.io.InputStreamReader(stream); breader = java.io.BufferedReader(ireader); Line = readLine(breader); disp(line);
Data Sets Archives at NCDC • NOAAPORT Operations. • Continuation of NCEP real time model component. • NCEP model initialization ingredients, “The minimum set” for model rerun/retrospective analysis ready observations & restart files.
Model Data Requirements from CLASS Current Archive: NOAAPort: 2TB/yr GDAS/SSI: 400Gb/yr NARR 10Tb Total 12.5Tb FY04 NCEP Hi-Res: +10TB/yr* Total 22.5Tb Legend Green- Existing Archive Blue- Expected FY03/04 FY03 * 5 year retention only Rutledge and Alpert 6/03
Model Data Req’s - NWP and GCM’s GCM- Global Climate Model Reanal- N. Am. Regional Reanalysis NWP- Numerical Weather Prediction * 5-year rotating NWP archive Alpert & Rutledge 6/03
RT NOMADS Server at NCEP • Two 1TB RAIDZONE servers • http://nomad2.ncep.noaa.gov • http://nomad1.ncep.noaa.gov (backup) • Documentation web page under construction • New disk space on order….
Non-Operational “Projects” can become NOMADS participants to display their data sets: NOMADS gives guidance to: • Install scripts for a GDS framework, • Setup GDS XML file – see example on web page, for example,… • Including GDS administration updates new additions transparently, • “newxml” update script – to automatically add new directories and files.
(RT) NOAMDS data sets …. • One data set (e.g, GRIB) provides the data for all access applications. • Control files (grib2ctl) and index files (gribmap) create unique metadata description. • GDS can read HDF, NETCDF as well as other formats.
NOMADS and the NCEP Real Time Component A solution for Recommendation 5 of “Fair Weather: Effective Partnership in Weather and Climate Services” • NWS should make its data and products available in Internet-accessible digital form. • Information held in digital databases should be based on widely recognized standards, formats, and metadata descriptions to ensure that data from different observing platforms, databases and models can be integrated and used by all interested parties in the weather and climate enterprise.