4 IFS @ ECMWF Chapter 14 – Data Flow difference between analysis (an), 4D-Var analysis (4v), 4D-increment analysis (4i) filesvariables coming out of the analysisvariables coming out of the forecasts – with reference times
5 Model levels and layers Documented accurate method to determine model level and layer coefficients.Tables and codes that provide themnetCDF file with valuesTricky matterGRIB files have model layer interfaces defined, not the levelContrast of ERA-15 (red) versus ERA-40 and ERA-Interim (blue)
6 High Resolution Model Level Data Two forms combined define atmosphereT255 spectral coefficients, Model Level FieldsZ, geopotential height of level 1T, temperature, 60 levelsW, vertical velocity, 60 levelsVO, relative vorticity, 60 levelsLNSP, log. of surface pressureD, divergence, 60 levelsN128 reduced Gaussian, Model Level FieldsQ, specific humidity, 60 levelsO3, ozone mass mixing ratio, 60 levelsCLWC, cloud liquid water content, 60 levelsCIWC, cloud ice water content, 60 levelsCC, cloud cover, 60 levelsdss.ucar.edu/datasets/ds627.0/docs/era_interim_grib_table.oper_an_ml.html
7 Horizontal Grids NCAR will compute Regular Gaussian (512x256)
8 Regular Gaussian (512x256) Transform to aid users N128 Reduced Gaussian Regular GaussianT255 Spectral Regular GaussianU and V winds are computed from VO and DProducts to be transformedAnalyses on model levels (ml), surface (sfc), pressure levels (pl), isentropic levels (pt), and potential vorticity levels (pv).Note: Important fields are in the forecast filesTransform only selected fields and forecast intervals
9 Surface Forecast Grids – Model resolution Initialization every 12 hoursGenerally, out to 240 hours3,6,9,12,15,18,21,24,30,36,42,48,60,72,84,96,108,120,132,144,156,168,180,192,204,216,228,240
10 Regular Gaussian (512x256), continued What high resolution data will ASR use?N128 and T255 spectral model level or regular Gaussian model level data created at NCAR?If regular Gaussian, then:We expect ASR to use the analysis (an) files.We will extract some fields from the forecast (fc) files.Are there any fields in the ‘fc’ files that you need?Planning just one pass on the ‘fc’ files to create regular GaussianLet’s get coordinated soon!
11 Regular Gaussian (512x256), continued Surface and Single level analysis (N128)47 fields
12 Status @ NCAR All products for January 1989 High resolution transformations (reg. gaussian)Decision still to be made on fields coming from the forecastsASRProductSize (GB/mn)✔an.ml21an.pl16an.pt4an.sfc2an.pv.2
13 Status @ NCAR Within a product there are 6-hourly synoptic files Our recommendation – if you plan to work with regular Gaussian model level fieldsASAP begin working with the January 1989 dataExamine the model level and surface level analyses.Examine forecasts for additional fields that ASR might need.Documents, metadata tables, test data (on NCAR/MSS)/DSS/DS627.0/ei.oper.an.ml/198901/ei.oper.an.ml.regn128sc/DSS/DS627.0/ei.oper.an.ml/198901/ei.oper.an.ml.regn128uv/DSS/DS627.0/ei.oper.an.sfc/198901/ei.oper.an.sfc.regn128sc/DSS/DS627.0/ei.oper.fc.sfc/198901/ei.oper.fc.sfc.regn128sc/DSS/DS627.0/ei.oper.fc.sfc/198901/ei.oper.fc.sfc.regn128sc
14 Status Future December 2007 data will arrive next Delivery – probably, mid-March, 2009Receive and process 1989 – 2007Receive 2008, about August, 20092009 updates by network transferLagging about 3 months behind real ECMWFEstablish the RDA online service. Product suite TBDAll data will be on the NCAR MSSHow will ASR get a copy of ERA-Interim?
15 ASR Data Management at NCAR Managed a component in the NCAR/CISL Research Data Archive (RDA)Planning for about 55 TB total (?)Duplicate copies on the NCAR MSSAll data available to the public (?)usage restriction?5-7 TB online, network access (TBD)Follow template used for JRA-25
16 What we need to know Was there a proposed data management plan? Is a product model like ERA-Interim suitablee.g. ml, pl, sfc, forecasts, etc. ?Will the netCDF file metadata be CF compliant?Good idea, enables tool compatibilityHow will the data files be structured?Synoptic 3-hourlySingle variable time series
17 What we need to knowHow to deal with the 2x horizontal resolution and polar projection?What interpolations from model coordinates will be done?Will pressure level data be computed?Will time averages be computede.g. monthly meansWill model assimilation feedback be added to the observations used, should that data be archived? In what format?
18 What we need to know What other organization will host ASR data? We must not duplicate effortsHow will we get the data to NCAR?Tapes, TB disks, network?Who will provide other organization bulk data delivery?How do we handle re-runs and fixes?
19 Contacts Steven Worley email@example.com Dave Stepaniak Chi-Fan Shih