WORLD METEOROLOGICAL ORGANIZATIONCOMMISSION FOR ATMOSPHERIC SCIENCESINTERNATIONAL CORE STEERING COMMITTEEFOR THORPEX
Ninth Session
WMO, Geneva (21-22 September 2011)

CAS/ICSC-9/DOC2.4.4(16 IX.2011)
Item: 2.4.4

Report of GIFS-TIGGE WG(Submitted by Zoltan Toth and Richard Swinbank)
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 main 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, fostering collaboration between operational
forecast centres and universities. Particular areas of research interest for the GIFS TIGGE
WG are:• a posteriori calibration of ensemble forecasts in all its forms (bias correction,downscaling, etc.);• optimum combination of information from ensemble members produced by multiplemodels;• use of information in control forecasts;• research to support probabilistic forecast products, including developments for GIFS.
The TIGGE data are also invaluable for a much wider range of research and development,
including the fields covered by the two other THORPEX working groups - Data Assimilation
and Observing System (DAOS) and Predictability and Dynamical Processes (PDP) - andother 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 2010/11. The following are of particular note:
8th GIFS-TIGGE WG, Geneva, February 2010
In order to start to develop links with the CBS Severe Weather Forecast Demonstration
Project (SWFDP), this meeting was scheduled in parallel with the SWFDP steering group,with a half-day joint session. First, the meeting reviewed progress with the TIGGE project,
and recent research based on TIGGE data. Second, the meeting agreed mechanisms forcollaboration between the GIFS-TIGGE project and the SWFDP, including representation ateach others meetings.
Workshop on Improvement of Weather and Environmental Prediction in Polar
Regions Oslo, October 2010.
Following the success of the International Polar Year (IPY), the workshop was held toconsider the establishment of a THORPEX Polar Research project. The GIFS-TIGGE WG
was represented at the workshop by L. Wilson. The project’s objectives would be to improveunderstanding of the impact of polar processes on polar weather, the assimilation of data inPolar Regions, and the prediction of high impact weather over Polar Regions. TIGGE wasconsidered to be an important example for the design of research databases to support
research studies on polar prediction.
7th International Workshop of Tropical Cyclones, la Reunion, November 2010

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R. Swinbank (co-chair) and T. Nakazawa (chief, WWRP) attended this meeting. They andseveral other WG members contributed to the report on probabilistic tropical cyclone
forecast products that was presented at a keynote session by G. Foley and C. Landsea.
The presentation included several types of probabilistic forecast which could contribute toGIFS. T. Nakazawa chaired a special focus session on the use of TIGGE for tropical
cyclone forecast products. The session opened with a presentation by R. Swinbank on
TIGGE and plans for development of GIFS, then T. Nakazawa and H. Yu then presented
examples of tropical cyclone forecast products developed for the projects currently inprogress in the NW Pacific. The special focus session was well attended with some good
discussion of the talks; this demonstrated a lot of interest in TIGGE from the TC community.
SWFDDP meeting, Wellington, November 2010E. Ebert attended a meeting of the Severe Weather Forecasting and Disaster RiskReduction Demonstration Project (SWFDDP) – the SW Pacific component of SWFDP, alsoin November. This helped build links between GIFS-TIGGE and the SWFDDP, and present
the potential use of probabilistic TC forecast products in that region. It also proved very
helpful to get a better understanding of the needs of users in that region.
Workshop of sub-seasonal to seasonal forecasting, Exeter, December 2010
The aims of this workshop were to review the current capabilities for sub-seasonal toseasonal prediction, to identify high-priority areas for research, and to foster international
collaboration. R. Swinbank gave a presentation on TIGGE, which was agreed to be a good
example of an international data archive. There was particular interest in development ofprecipitation products based on TIGGE forecasts, for regions including the La Plata Basin inS. America and parts of Africa. The meeting recommended that an international research
project on sub-seasonal prediction be established.
9th GIFS-TIGGE WG, Geneva, September 2011
The meeting first reviewed progress of the TIGGE project. Since the previous meeting,several centres have implemented improvements to their global ensemble prediction
systems that are contributed to the TIGGE archive, including some significant improvements
in model resolution. The archive centres have also benefited from improvements, including
developments to the model validation portal at NCAR; enhancements to the ECMWF portal
are also planned, supported by funding from the EU via the GEOWOW project.
To support development of GIFS, websites have been established to display prototype
products to support forecasts of tropical cyclones, and other high-impact weather events.
Two representatives of the SWFDP steering group attended the meeting. It was agreed thatthe SWFDP would provide the GIFS-TIGGE working group with feedback on the prototype
products, to establish which products could be adapted for use and evaluation in theSWFDP subprojects.
As noted in the introduction, the GIFS-TIGGE has taken a particular interest in research on
ensemble calibration and combination, plus development and evaluation of forecast products.
It was agreed that in future the group should also be a forum to discuss research anddevelopment of EPS improvements, including defining initial conditions for ensemble
forecasts and taking account of the effect of model errors.
The future membership of the group was considered, and the proposed list of members isshown in Annex A. Annex B lists the actions for WG members and associates that wereagreed at the meeting.
3.

TIGGE activities

The three archive and data portal centres (ECMWF, NCAR and CMA) each hold copies of
the global TIGGE ensemble forecast data set. The archives start in October 2006, so almost
5 years of data are now available from some of the data providers. The archive contains

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forecasts from ten global weather prediction centres, although at the time of writing deliveryof new forecasts has temporarily been suspended by two of the data providers.
Access to the data set is given to researchers, following a simple registration process.
Normally access is granted with a delay of 48 hours after the initial time of the forecast. Real
time access is granted in some cases e.g. for field experiments and projects of specialinterest. Registration for real time access is handled by the WWRP-THORPEX International
Programme Office at the WMO. There are a large number of registered users across thethree archive centres, but a more meaningful statistic is that there are about 60 active
archive users each month – see Figure 1 (note that CMA usage data is incomplete). This isthought to underestimate the number of active users of TIGGE data, since some users
access the data via other routes.

10000

120

1000

90

Volume (GB)

150

100

60

1030

1

Number of Users (Count)2011 TIGGE Archive Usage (All Portals)
100000Vol Accessed (GB)Vol Delivered (GB)# Active Users

0JanFebMarAprMayJunJulAug

MonthFigure 1 – Time series of monthly usage of TIGGE archive portals during 2011
A TIGGE-LAM expert panel has been established to focus on regional ensemble forecasting,to complement the global focus of the GIFS-TIGGE WG. 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 TIGGE-LAM group has recentlybeen restructured into regional sub-groups to allow better focus on regional activities.
Regional sub-groups have been formed for North America, Europe, Asia, South America andAfrica. The TIGGE-LAM group has also established a strong working relationship with theWWRP/MWFR (Mesoscale Weather Forecasting Research) group.
A major article describing the TIGGE project, and some early results, was published in theBulletin of the American Meteorological Society (Bougeault et al, 2010). Many research
projects using TIGGE data are underway, and a steady stream of papers is starting toappear in scientific journals. Up to the end of 2010, 43 articles related to TIGGE have been
published in the scientific literature. A research topic particularly relevant to TIGGE is thebenefit of combining ensemble prediction from multiple centres. Research studies havedemonstrated that combination of multiple ensembles improves the skill of forecasts ofsurface air temperatures, compared to any single ensemble. More recent (as yetunpublished) studies have also confirmed the improved skill in precipitation forecasts.

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TIGGE data has also been used for a range of predictability studies, including forecasts ofextratropical cyclone and predictions of tropical cyclone tracks.
In order to increase awareness of TIGGE, the working group, with support from theTHORPEX IPO, has produced a leaflet to help publicise the TIGGE project at scientificmeetings. Additional information about the TIGGE project and plans for GIFS has also been
added to the TIGGE website, which is hosted by ECMWF. As well as being part ofTHORPEX, TIGGE is GEO (Group on Earth Observations) task WE-06-03. A section
illustrating the use of TIGGE data to support the forecasting of Tropical Cyclones wasincluded in the GEO book “Crafting Geoinformation” (GEO, 2010), and an article based on
the same forecast case study was published in the WMO Bulletin (Mc Caslin et al, 2010)
4.

GIFS developments

TIGGE is paving the way towards the development of a Global Interactive Forecasting
System (GIFS), as envisaged in the THORPEX international research implementation plan.
In order to carry this work forward, a GIFS development project has been established. A
phased approach has been adopted, starting with the real-time exchange of tropical cyclone
track forecasts, using a new XML-based format (known as CXML), during the T-PARC field
programme. The exchange of tropical cyclone forecasts has been maintained, for theongoing NorthWest Pacific Tropical Cyclone Project and other regional demonstration
projects.
The aim of the GIFS development project is to establish a framework for the experimental
provision of products to enhance the prediction of high-impact weather and evaluation of
those products. The GIFS development project will support the development of additional
forecast products to contribute to the regional subprojects of the SWFDP. This project will
enhance links between WWRP-THORPEX and the operational weather forecasting
community, and allow products based on TIGGE forecasts and multi-model ensemble tosupplement the data available from the SWFDP to operational forecasters. Several of thepartners in the GIFS-TIGGE project have developed products that use the tropical cyclone
forecasts exchanged using CXML. MRI/JMA has developed a website to display tropical
cyclone forecast products for the NW Pacific project, while Météo-France has set up a TC
website to support the Southern Africa SWFDP subproject. MRI/JMA has also developed awebsite of prototype high-impact weather products based on gridded fields from the TIGGE
data set. It is planned that these products would form the basis for products to be used insome of the SWFDP regional subprojects. Objective verification and user evaluation of theGIFS products will be a key part of this collaboration.
References
Bougeault, P., Z. Toth, C. Bishop, Barbara Brown, David Burridge, De Hui Chen, Beth Ebert,
Manuel Fuentes, Tom Hamill, Ken Mylne, Jean Nicolau, Tiziana Paccagnella, Young-YounPark, David Parsons, Baudouin Raoult, Doug Schuster, Pedro Silva Dias, Richard Swinbank,
Yoshiaki Takeuchi, Warren Tennant, Laurie Wilson and Steve Worley, 2010: The THORPEXInteractive Grand Global Ensemble (TIGGE). Bull. Amer. Meteorol. Soc., 91, 1059–1072.
GEO, 2010: “Crafting geoinformation”, available
documents/geo_vii/geo7_crafting_geoinformation.pdf

fromwww.earthobservations.org/

McCaslin, P., T. Nakazawa, R. Swinbank and Z. Toth, 2010: Improving cyclone warning
Case study: Philippines. WMO Bulletin, 59(2), 79-81.

CAS/ICSC-9/Doc.2.4.4, p. 5

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

Young-Youn Park, co chair

KMA, Korea

Laurie Wilson

EC, Canada

Tiziana Paccagnella

ARPA-SIM, Italy

Gong Jiandong

CMA, China

David Richardson

ECMWF, UK

Masayuki Kyouda

JMA, Japan

Michael Naughton

BoM, Australia

Philippe Arbogast

Meteo-France, France

Osvaldo Moraes

CPTEC, Brazil

Doug Schuster

NCAR, USA

Yuejian Zhu

NOAA/NCEP, USA

The entries in bold italics are changes since ICSC-8 and require approval by ICSC.

CAS/ICSC-9/Doc.2.4.4, p. 6Annex B: Actions from 9th meeting of GIFS-TIGGE WG
Permanent Actions
Action P.1: All archive centres to update statistics on TIGGE data users on an annual basis(end of each year), using similar statistics for users, actives users, etc. Doug Schuster tocoordinate.
Action P.2: Young-youn Park and Mio Matsueda to carry out literature search for papers
based on TIGGE data, and summarise results. Archive centres to ask users to inform themwhen TIGGE papers are written, to enable the list of TIGGE publications to be kept up todate.
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.
New & amended Actions
Action 9.2.1: Co-chairs to establish contact with Thomas Jung (chair of polar project),
establishing collaboration with polar project
Action 9.2.2: Co-chairs to establish links with new sub-seasonal to seasonal prediction
project especially David Anderson (consultant), and Frederic Vitart and Andrew Robertson(co-chairs) to maximise compatibility between the new project archive and the existing
TIGGE archive.
Action 9.2.3: Co-chairs to report on status of collaboration with SWFDP project atWWRP/JSC5 meeting, Spring 2012.
Action 9.2.4: WG members to consider developing an article reviewing TIGGE research inrefereed literature, for discussion next WG meeting.
Action 9.3.1: All data providers are encouraged to provide T+0 data at 0 and 12 UT at least,
6 hourly if available, in consultation with archive centres.
Action 9.3.2: WG members to inform JMA by Nov 11 (ET-EPS meeting) what they propose
to supply to WMO Lead Centre on EPS verification, and when.
Action 9.3.3: WG members to consider joining SNAP (Stratospheric Network on Assessmentof Predictability) project and contribute ensemble forecast output fields to the SNAP projectarchive.
Action 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 11.
Action 9.5.1: Co-chairs to arrange representation at the SWFDP SG meeting in early 2012
and use this meeting to establish links with RSMCs Pretoria, Wellington & Nairobi
Action 9.6.1: Tetsuo Nakazawa to request MRI to prepare questionnaire to obtain feedback
from users of websites, including suggestions for improvement
Action 9.6.2: WG members encouraged to contribute additional products to the MRI TC
website.
Action 9.6.3: Co-chairs to consider inviting an expert from HFIP to next WG meeting.
Action 9.6.4: TIGGE-LAM panel is encouraged to assess skill of TC intensity forecasts inhigh-resolution models.

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Action 9.6.5: All data providers are invited to add central pressure information and max windinformation to CXML, using conventions to be agreed, based on current practices.
Action 9.6.6: All data providers are encouraged to carry out TC forecast verification
Action 9.7.1: Co-chairs to invite Celeste Saulo to submit a formal application for a WWRP
FDP/RDP based on weather elements of La Plata Basin project, in order to formalise links
with GIFS-TIGGE.
Action 9.7.2: David Richardson to provide a report regarding application of EPS tohydrology.
Action 9.7.3: Mio Matsueda to draft brief documentation , including health warnings, ofextreme weather products and work with co-chairs to finalise by Feb 2012
Action 9.7.4: SWFDP RSMCs invited to evaluate prototype products on Mio Matsueda’s
website and report back to next GIFS-TIGGE WG meeting, to assess requirements for nearreal-time versions of the products.
Action 9.8.1: Co-chairs to create new agenda item on EPS improvement for next WGmeeting.
Action 9.8.2: KMA, NCEP, MO, MF, ECMWF, JMA, CMA to nominate people to form a TC
focus group which will prepare a report on TC forecast product developments for next WG
meeting. Names to be sent to co-chairs, by end Oct 2011. The WG seeks a volunteer to act
as focal point for this group.
Action 9.8.3: All data providers to nominate people to form a precipitation focus group which
will prepare a report on precipitation forecast product developments for next WG meeting.
Names to be sent to co-chairs, by end Oct 2011. The WG seeks a volunteer to act as focal
point for this group.
Action 9.10.1: Co–chairs to contact Pedro Silva Dias to request a nomination of a new
representative from CPTEC, before ICSC-9 meeting.