WORLD METEOROLOGICAL ORGANIZATIONCOMMISSION FOR ATMOSPHERIC SCIENCESINTERNATIONAL CORE STEERING COMMITTEEFOR THORPEX
Tenth Session
WMO, Geneva (3-5 October 2012)

CAS/ICSC-10/Doc 2.4.4(dd IX.2012)
Item: 2.4.4

Report of GIFS-TIGGE WG(Submitted by Richard Swinbank and Masayuki Kyouda)
1.

Introduction

The GIFS-TIGGE working group was established in 2005, first to manage the TIGGE(THORPEX Interactive Grand Global Ensemble) project to support research on ensemble
prediction, and second to support the application of ensemble forecasts as the basis of afuture Global Interactive Forecast System (GIFS).
The initial focus of the working group has been the establishment of the TIGGE data set,
comprising regular ensemble forecasts from ten of the leading global numerical weather
prediction centres. These data are made available for use by the international researchcommunity through three archive centres at ECMWF, NCAR and CMA. The archives start inOctober 2006, so over 5 years of data are now available from some of the data providers.
During that period, a number of improvements have been implemented by the data providers,which are reflected in the TIGGE archive contents.
The working group also takes a strong interest in research related to ensemble prediction,
including: development of improved ensemble prediction systems; calibration of ensemble
forecasts (including bias correction and downscaling); combination of ensemble members
produced by multiple prediction systems; and development of probabilistic forecast products.
The TIGGE data are also invaluable for a wide of research and development work, including
the fields covered by the two other THORPEX working groups - Data Assimilation andObserving System (DAOS) and Predictability and Dynamical Processes (PDP) - and other
WWRP working groups, including the Working Group on Numerical Experimentation(WGNE), Socio-economic Research and Applications (SERA) and the Joint Working Groupon Forecast Verification Research (JWGFVR).
2.

Meetings to progress TIGGE and GIFS

Members of the GIFS-TIGGE working group contributed to several meetings andconferences during 2011/12. The following are of particular note:
SWFDP Steering Group meeting
Young-Youn Park attended the meeting on behalf of the GIFS-TIGGE WG and gave apresentation on ensemble TC products and other MRI products. The main concern of the SGwas the delay in receiving the products which tended to handicap assessment andevaluation which were best carried out nearer to real time. There were also concerns about
the complexity of the information – it was preferable to present only the best and most useful
information. It became clear that a more general questionnaire than that previously
developed by MRI was needed to provide feedback to guide future GIFS productdevelopments.
Africa Regional Committee meeting, May 2012
Richard Swinbank attended the Africa regional committee meeting, together withrepresentatives from other THORPEX working groups. The priority of the meeting was todecide the research priorities of the group for the next few years. It was agreed to focus oncompleting and publishing four case studies with the help of the THORPEX WGs. Thesecomprise severe flooding events across Africa, all of which had major socio-economic
impacts. Details are to be found on the AfClix website.

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10th GIFS-TIGGE WG, Boulder, June 2012
One aim of the meeting was to review and consolidate recent progress with GIFS-TIGGE
project. The success in establishing the TIGGE archive has enabled a range of research
projects to be carried out; the meeting included several presentation of research related toTIGGE. A particular focus was the development of new ensemble-based products which will
be evaluated in conjunction with the Severe Weather Forecast Demonstration Project(SWFDP). The working group spent time to discuss the future of TIGGE and GIFS, anddiscussing possible arrangements for a future programme to follow THORPEX after the endof 2014.
The future membership of the group was considered, and the proposed list of members isshown in Annex A. Annex B lists the actions that were agreed at the meeting.
An afternoon workshop on developments in Ensemble Prediction Systems was arranged inconjunction with the working group meeting. It included presentations by both members of
the working group and ensemble scientists from NCAR and NOAA.
ICDM 2012 workshop on ‘Dynamics and Predictability of High-impact weather andextreme climate events’, August 2012.
Richard Swinbank was co-chair of the scientific organising committee for this workshop,
which was sponsored by WWRP-THORPEX, WCRP, IAMAS, IUGG and a range of Chinesesponsors. The workshop was designed to bring together scientists from both weather
forecasting and climate prediction communities to discuss the dynamics and predictability ofsevere events at all timescales. The presentations covered a range of topics relevant toTHORPEX including tropical and mid-latitude cyclones and the use of ensembles forprobabilistic predictions of severe weather events. The workshop included a panel
discussion of the THORPEX legacy and priorities for future research, chaired by Tetsuo
Nakazawa.
3.

TIGGE activities

Researchers can readily access the data set after a simple registration process. Normallyaccess is granted with a delay of 48 hours after the initial time of the forecast. There are alarge number of registered users across the three archive centres, but a more meaningfulstatistic is that there are almost 100 active archive users each month – see Figure 1. This isthought to underestimate the number of active users of TIGGE data, since some users may
access the data on behalf of several colleagues, for example.
The GEOWOW project, funded under the EU FP7 programme, was started in autumn 2011.
This project is supporting ongoing developments to TIGGE, including improved treatment oftime-series data and the provision of data in NETCDF format as an alternative to GRIB2.
The main focus of GEOWOW is the development of GEOSS (Global Earth Observation
System of Systems) which will facilitate the multi-disciplinary use of TIGGE data.
The TIGGE dataset is a rich resource for a range of research studies, and the number ofscientific publication based on TIGGE data continues to grow. Some notable recent
publications include a comparison of the prediction of southern hemisphere cyclones(Froude, 2011), the prediction of the Madden-Julian Oscillation (Matsueda and Endo, 2011)
and a study of the impact of extra-tropical transition of tropical cyclones (Keller et al, 2011).
There is a continuing interest in the use of reforecast datasets to improve the calibration ofensemble forecasts; recent comparisons between multi-model and reforecast-calibrated
techniques have been published by Hagedorn et al (2012) and Hamill (2012).
The number of scientific studies that are based on TIGGE illustrate the increasing
acceptance by universities and funding agencies of the value of the TIGGE dataset.

CAS/ICSC-10/Doc.n.n.n, p. 3
Feedback received, via colleagues on the PDP WG and from scientific meetings such as theICDM2012 workshop, underline the value of maintaining and adding to the dataset.

150

10000120

10009010060

10301Number of Users (Count)

Volume (GB)2011/2012 TIGGE Archive Usage (All Portals)
100000Vol Accessed (GB)Vol Delivered (GB)# Active Users

0Jan‐11 Feb‐11 Mar‐ Apr‐11 May‐ Jun‐11 Jul‐11 Aug‐11 Sep‐11 Oct‐11 Nov‐11 Dec‐11 Jan‐12 Feb‐121111MonthFigure 1 – Time series of monthly usage of TIGGE archive portals through 2011/12To complement the global focus of the GIFS-TIGGE WG, a TIGGE-LAM expert panel has
been established to focus on regional ensemble forecasting. The panel facilitates theinteroperability of the different regional modelling systems contributing and coordinates thearchiving of limited-area ensemble forecasts. The three TIGGE archive centres have agreed
to host a sub-set of high priority TIGGE-LAM data; the development of that capability at
ECMWF is supported through the GEOWOW project. The TIGGE-LAM group has
established a strong working relationship with the WWRP/MWFR (Mesoscale WeatherForecasting Research) group, but also needs to maintain strong technical and scientific links
with the GIFS-TIGGE working group.
4.

GIFS developments

Ensemble forecast data in the TIGGE database provides a valuable resource to develop
prototype products to support forecasts of high-impact weather. The working group
established a GIFS development project to support the development of additional forecast
products to contribute to the regional subprojects of the SWFDP. This will enhance links
between WWRP-THORPEX and the operational weather forecasting community, and allow
products based on multi-model ensemble forecasts from the GIFS-TIGGE partners tosupplement the data available from the SWFDP to operational forecasters.
Several of the partners have developed products to support forecasts of high-impact weather.
These developments started with products based on the exchange of tropical cyclone track
forecasts, using a new XML-based format (known as CXML), which was initiated during theT-PARC field programme. The exchange of tropical cyclone forecasts has been maintained,
for the ongoing North West Pacific Tropical Cyclone Project and other regional
demonstration projects. More recently, some prototype products have been developed tohighlight the risks of heavy rainfall, string winds and extreme temperatures.
In order to guide future developments, a questionnaire was distributed via the SWFDP. The
results from the survey confirmed that probabilistic products focused on tropical cyclones,
heavy precipitation and strong winds are particularly important to forecasters, but otherCAS/ICSC-10/Doc.n.n.n, p. 4
issues including predictions of sea state also need to be addressed. The main focus offorecasters is on the short-range, underlining the need to be able to provide ensemble-based
products as close to real time as possible.
5.

Future Plans

Following the discussion at the working group meeting, a submission was prepared for theICSC consultation on a possible THORPEX follow-on programme. The paper reiterates thebenefit of continuing the archiving of TIGGE data. The GIFS-TIGGE WG proposes a future
Predictability and Ensemble Forecasting working group, to strengthen the scientific focus on
ensemble forecasting as part of the core WWRP programme. For further details, please see
the GIFS-TIGGE WG submission, which is included as an annex to the ICSC-10 THORPEX
legacy paper.
References
Froude, L. S. R., 2011: TIGGE: Comparison of the Prediction of Southern Hemisphere
Extratropical Cyclones by Different Ensemble Prediction Systems. Weather and Forecasting,
26,388-398.
Hagedorn, R., Buizza, R., Hamill, T. M., Leutbecher, M. and Palmer, T. N., 2012, Comparing
TIGGE multimodel forecasts with reforecast-calibrated ECMWF ensemble forecasts. Q.J.R.
Meteorol. Soc. doi: 10.1002/qj.1895
Hamill, Thomas M., 2012, Verification of TIGGE Multi-model and ECMWF ReforecastCalibrated Probabilistic Precipitation Forecasts over the Contiguous US Monthly WeatherReview. 140, 2232-2252
Keller, J. H., S. C. Jones, J. L. Evans, and P. A. Harr, 2011: Characteristics of the TIGGE
multimodel ensemble prediction system in representing forecast variability associated withextratropical transition, Geophys. Res. Lett., 38, L12802, doi:10.1029/2011GL047275
Matsueda, M., H. Endo, 2011: Verification of medium-range MJO forecasts with TIGGE.
Geophys. Res. Lett., 38, L11801, doi:10.1029/2011GL047480.

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Annex A: Proposed GIFS-TIGGE WG membership, for endorsement by ICSC
Richard Swinbank, co-chair,Met Office, UK

Masayuki Kyouda, co chair

JMA, Japan

Philippe Arbogast

Météo-France, FranceJiandong Gong

CMA, China

Seung-Woo Lee

KMA, Korea

Osvaldo Moraes

CPTEC, Brazil

Michael Naughton

BoM, Australia

Tiziana Paccagnella

ARPA-SIM, Italy

David Richardson

ECMWF, UK

Doug Schuster

NCAR, USA

Laurie Wilson

EC, Canada

Yuejian Zhu

NOAA/NCEP, USA

The entries in bold italics are changes since ICSC-9 and require approval by ICSC.

CAS/ICSC-10/Doc.n.n.n, p. 6Annex B: Actions from 10th meeting of GIFS-TIGGE WG
Permanent ActionsAction P.1: All archive centres to update statistics on TIGGE data users on an annualbasis (end of each year), using similar statistics for users, actives users, etc. Doug Schuster
to coordinate.
Action P.2: Yuejian Zhu to carry out literature search for papers based on TIGGE data on
an annual basis (end of each year), and summarise results. Archive centres to ask users toinform them when TIGGE papers are written, to enable the list of TIGGE publications to be
kept up to date.
Action P.3: All data providers to provide model descriptions in agreed Excel format and toupdate the files after significant changes and send to ECMWF.
Action P.4: Co‐chairs to request reports before each WG meeting on all actions, plus
relevant progress reports.
Actions carried forward from GIFS-TIGGE 9Action 9.3.4: WG members to consider adding to training material on the TIGGE data
portals, including data access and manipulation examples, to help potential users of theTIGGE archive.
Action 9.4.1: Tiziana Paccagnella to arrange for report on European TIGGE-LAM
interoperability to be circulated for the benefit of related activities in other regions by Dec
2012.
Actions from GIFS-TIGGE 10
Action 10.3.1: Doug Schuster, David Richardson, Jiandong Gong to advertise the NCAR
model validation portal on the other archive data portals and TIGGE website.
Action 10.3.2: Yuejian Zhu to establish the possibilities and practicalities of providing theNCEP data to the ECMWF archive centre in the event that the NCAR archive centre ceases
to function in the post THORPEX era.
Action 10.4.1: Co-chair to contact PDP co-chairs to agree the structure of a TIGGE
research review paper in consultation with Laurie Wilson, with the intention of a good draft
available by the next WG meeting. Subsequently, the paper should be submitted for
publication in the scientific literature
Action 10.5.1: Co-chair & Christopher Cunningham to request Mio Matsueda to generate
severe weather products for the La Plata Basin as soon as possible.
Action 10.5.2: Met Office, JMA and MRI to develop a joint proposal for delivery of products
in near real time to the SWFDPs, in consultation with ECMWF and NCEP, by October 2012.
The Met Office is the lead organisation under the GEOWOW project. This proposal should
consider calibration, verification and feasibility issues and establish timescales forimplementation.
Action 10.6.1: Tiziana Paccagnella to contact the Shanghai Typhoon Institute concerning
the use of regional models in the TLFDP and assessment of the skill of TC intensity
forecasts in high resolution models
Action 10.6.2: Co-chair to review the completed SWFDP questionnaires to see if there are
any implications for the content of CXML messages.
Action 10.6.3: The WG encourages providing centres to include information on forming
storms in CXML messages (initially using location / time as identification and subsequently
discuss a naming convention).

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Action 10.6.4: IPO to check the original letter issued on CXML messages and the replies
from the centres.
Action 10.7.1: Christopher Cunningham to consult with Tiziana Paccagnella to ensuretransfer of the benefits from the TIGGE-LAM work to the La Plata Basin Project
Action 10.7.2: Co-Chair to contact Dmitry Kiktev (Sochi 2014) to discuss possible
requirements in detailDecision 10.8.1: The WG supports close links between TIGGE-LAM panel and theMesoscale WG. But it does not support any organisational changes concerning TIGGE-LAM
at this time, in view of the impending completion of THORPEX.
Action 10.9.1: Co-chair to draft a one-page summary on WG input concerning the postTHORPEX arrangements to the ICSC, then circulate to WG members and PDP co-chairs,
before submission to the IPO by 15 July.
Action 10.10.1: Laurie Wilson to contact David Richardson concerning the selection oflocations for time-series data from the ECMWF TIGGE archive for the GEOWOW project
Action 10.11.1: Co-chair & IPO to identify a new co-chair and submit the nomination, withany other recommended WG membership changes, to ICSC-10.