1. TIGGE Archives and Access
Data Centers Overview
Three mirrored international repositories
ECMWF, NCAR, and CMA
Receive ensemble forecasts from up to 10 providers
Use network data transport software designed by UCAR’s Unidata (IDD/LDM)
Provide portals for data discovery and access
Provide user registration and data usage monitoring
Policy, public open access for research, access delay of 48 hours after forecast initialization time
Maintain some data online
Provide access to long-term archive through a request system

2. TIGGE Archive and Access
Archived Data Definitions
Required conformance from all providers on:
GRIB2 WMO format
Variables, levels, and units
Details at,
Briefly: Eight P levels ( hPa) with five variables (u, v, q, t, gh), 26 single level fields, three variables (pt, u, v) on ± 2 PVU, and PV on  = 320K
All ensemble members
All forecast times ( e.g. 1x, 2x, or 4x daily)
Non-conformance allowance for:
2D horizontal resolution
Each provider is free to choose their own resolution, i.e. native grid resolution
Highlights that serve to define what a TIGGE archive center is.

3. TIGGE Archive and Access
NCAR Archive Status
Receiving TIGGE conforming data for ECMWF and UKMO
GB/hour
IDD/LDM data transport method is configured to assure complete archive receipt
Processes to check data validity are ready
Processes to create MSS archive are ready
TIGGE portal, the user interface, is under development
New online storage (6TB) has been purchased
New dedicated server to receive and distribute TIGGE is being installed now
Target archive start date, September 2006

4. TIGGE Archive and Access
Data Provider Status
ECMWF and UKMO are ready
Brazil (CPTEC)
Verified IDD/LDM data transport
Preparing software to produce TIGGE GRIB2 data
Japan (JMA)
ECMWF will provide JMA data distribution soon - a partial TIGGE parameter set
Beginning testing IDD/LDM at JMA
Spring 2007, JMA will provide full TIGGE conforming data set, independently.
U.S. (NCEP)
Will provide TIGGE conforming data as resources allow
Possible partial TIGGE contribution by January 2007
Others, no direct interactions yet, but work is underway

5. TIGGE Archive and Access
Access features when archiving begins:
TIGGE portal will describe all available data
Archive file downloads with selection by:
Data provider and Model
Forecast initialization time
Forecast time step
Product group (data on pressure levels, single level fields, data on ± 2 PVU, and on  = 320K)
One month of data online, and all data on the NCAR MSS
TIGGE data analysis using NCAR facilities could be a good approach - no need to download the data.
Future access features
Users can select any data and choose a desired regular latitude x longitude grid to be output
Potentially, choose one of several output formats also
NOTE: This is highly dependent on TIGGE GRIB2 software and tool development

6. TIGGE Archive and Access
Software and User Tools for TIGGE
Status
Currently, lacking software to do basic GRIB2 manipulations
Why? GRIB2 is just recently been defined
The format structure is very different from GRIB1
This is a significant area of concern and will be an area of user dissatisfaction, at least in the early going
Paths forward
Each data provider is required to provide software to the archive centers that:
Reads and decodes their TIGGE native grid GRIB2 files
Interpolates the native grids to arbitrary lat. x lon. grids
Application programmers are adapting tools to accept TIGGE GRIB2, e.g. NCAR, and Java based Unidata

7. TIGGE Archive and Access
Software and User Tools for TIGGE, continued
Challenges
At the Archive Centers
Assuring the software runs correctly and gives accurate results
Resolve compiler and machine dependencies
Preparing software packages for users
Support users with consulting, debugging, and Q and A
In the more distant future
Creating systems, with adequate computational resources, to derive user selected subsets
TIGGE is a non-funded activity at NCAR
Challenges cannot be met with current staffing
At the User sites
Using multiple software packages to manipulate multiple ensemble products will be complicated.