TIGGE Data Archive and Access at NCAR November 2008 November 2008 Steven Worley National Center for Atmospheric Research Boulder, Colorado, U.S.A.

Topic Outline l Project Definition l Archive Summary l Data Description l Provider Summary l NCAR’s portal and access

Project Outline TIGGE, the THe Observing System Research and Predictability EXperiment (THORPEX) Interactive Grand Global Ensemble l WMO World Weather Research Programme l Goal, accelerate improvements in 1-day to 14-day high-impact weather forecasts l How –Enhanced international collaboration on ensemble prediction –New methods for combining ensembles from different sources –Deeper understanding of forecast errors l Purpose –Prototype for a future Global Interactive Forecast System (GIFS)

Phase I Archive Centers Archive Centers  NCAR  ECMWF  China Meteorological Administration (CMA) Archive Centers build identical archives, i.e. all the data.

TIGGE Archive Centers and Data Providers Archive Centre Current Data Provider NCAR NCEP CMC UKMO ECMWF MeteoFrance JMA KMA CMA BoM CPTEC IDD/LDM HTTP FTP IDD/LDM Internet Data Distribution / Local Data Manager Commodity internet application to send and receive data

Brief Data Description Global Ensemble Forecasts Five parameters on eight pressure levels Z, Q, T, U, V 1000, 925, 850, 700, 500, 300, 250, 200 hPa Z at 50 hPa Potential Vorticity on 320 K Potential Temperature Surface (θ) θ, U, V on  2 potential vorticity surface 28 Surface/Single level parameters

Summary of Data Providers, March ‘08

VariableLvLECWFUKMOJMANCEPCMACMCBOMMetFKMACPTC Geopotential ZPL Specific HPL T U-velocityPL V-velocityPL Potential VorPT Potential TPV U-velocityPV V-VelocityPV U 10mSL V 10mSL CAPESL Conv. Inhib.SL Land-seaSL Mean SLPSL Orog.SL Skin TSL Snow D. H20SL Snow F. H20SL TIGGE Archive Completeness, 02/2008 PL = Pressure Level, PT = 320K Theta Level, SL = Single/Surface Level

VariableLvLECWFUKMOJMANCEPCMACMCBOMMetFKMACPTC Soil Moist.SL Soil TSL Sunshine D.SL Surf. DPTSL Surf. ATmaxSL Surf. ATminSL Surf. ATSL Surf. PSL LW Rad. OutSL LH fluxSL Net RadSL Net Therm. RadSL Sensible Rad.SL Cloud CovSL Column WaterSL PrecipitationSL Wilt. PointSL Field Cap.SL TIGGE Archive Completeness, 02/2008 PL = Pressure Level, PT = 320K Theta Level, SL = Single/Surface Level

The Data Management Challenges Anomalies between centers l Native horizontal resolution l Number of ensemble members l Number of forecast initialization times (1, 2, 4x daily) l Forecast increment time period l Forecast length l Number of fields provided l Internal file compression (e.g. jpg) was not specified Influence on Research l User interface must inform users - commonalities constrain research

NCAR TIGGE Portal Address: Main Features –Registration and Login –Get Data –User Tools –Documentation and Linkages –Technical and Community Supported Help

Dates Center File Type Forecast Time Forecast Duration

Get Forecast Data NCAR online file archive Selection options Center(s) Date File type (sl, pl, etc) Initialization time Forecast length Download Options Point and click using browser, one file at a time Script to run on local machine User and password encrypted ‘wget’ commands background process to access all files User customized files Selection options Same as for files, plus Parameter Regridding Spatial subsets Formats, GRIB2, netCDF Delayed ModeReal Time Two User Interfaces

Tropical Cyclone Track Data Direct Download Only, format Simple directory system, center/year/month Web address, dss.ucar.edu/datasets/ds330.3 Update Frequency 12 hours Size 6GB

Public Announcement l EOS, Transactions, American Geophysical Union, Vol. 89, Number 36, September 2, 2008 –Title: Improving High-Impact Weather Forecasts –Included an online supplement

END Steven Worley