Report from GIFS-TIGGE working group Richard Swinbank, and Zoltan Toth, with thanks to the GIFS-TIGGE working group, THORPEX IPO and other colleagues Presentation for THORPEX ICSC-9, September 2011

TIGGE and GIFS  TIGGE  TIGGE archive status  TIGGE research  GIFS developments  Examples of products based on TIGGE data  Building links with CBS & operational forecasting

TIGGE project  Since 2006, TIGGE has been collecting ensemble predictions from 10 of the leading global forecast centres.  TIGGE data are made available after a 48-hour delay, to support research on probabilistic forecasting methods, predictability and dynamical processes.  50+ TIGGE articles published in scientific literature.

TIGGE Archive Usage (NCAR + ECMWF) NB. CMA usage data incomplete.

TIGGE-LAM: TIGGE for limited-area models To complement the global TIGGE project, the TIGGE-LAM panel, chaired by Tiziana Paccagnella (ARPA-SIM), supports the coordinated development of Limited Area Model Ensemble Prediction Systems.  This Panel works in close coordination with pre-existing LAM EPS initiatives, the GIFS-TIGGE WG, the WWRP Mesoscale Weather Forecasting Research group, and THORPEX regional committees.  The panel facilitates the interoperability of the different modelling systems and coordinates the archiving of limited-area ensemble forecasts – the three TIGGE archive centres have agreed to host a sub-set of high priority data  The TIGGE LAM Panel is being restructured in Regional sub-groups to facilitate the focus on regional activities.  The TIGGE-LAM plan is available from the TIGGE-LAM website

TIGGE research example (1): Precipitation forecasts over USA  24 hour accumulations, data from 1 July 2010 to 31 October  20 members each from ECMWF, NCEP, UK Met Office, Canadian Meteorological Centre.  80-member, equally weighted, multi-model ensemble verified as well.  Verification follows Hamill and Juras (QJ, Oct 2006) to avoid over-estimating skill due to variations in climatology.  Conclusions:  ECMWF generally most skillful.  Multi-model beats all. Tom Hamill

Spatiotemporal Behaviour of TIGGE forecast perturbations Kipling et al, 2011 M(t) (log) perturbation amplitude V(t) (log) variance Indicates how spatial correlation & localisation vary as perturbations grow.

Publicising TIGGE  Major Article in BAMS  New leaflet to publicise TIGGE to researchers  Contribution to GEO book “Crafting Geoinformation”  Tropical cyclone case study in WMO Bulletin  Update of TIGGE website

TIGGE Research focus Following the successful establishment of the TIGGE dataset, the main focus of the GIFS-TIGGE working group has shifted towards research on ensemble forecasting. Current emphasis:  Calibration and combination methods  Bias correction, downscaling  Multi-model ensembles; reforecasts  Development of probabilistic forecast products – GIFS development  Tropical cyclones (CXML-based)  Gridded data: heavy precipitation; strong winds Focus has been on downstream application of ensembles, rather than on improving EPSs

TIGGE Research needs & priorities  But other important areas for EPSs include  Initial conditions – link with ensemble data assimilation (DAOS)  Representing model error – stochastic physics (PDP, WGNE)  Verification of ensemble forecasts (JWGFVR)  Seamless forecasting – links with sub-seasonal forecasting (new project)  Convective-scale ensembles (TIGGE-LAM, MWFR)  These areas, particularly first two, are important for improving EPS skill and products.  TIGGE is an excellent resource for comparing EPS techniques.

Evolution of TIGGE & GIFS  We propose that the GIFS-TIGGE should also be a forum to focus on R&D directed at improving our EPS systems, to help us develop a “virtuous circle”.  We will have a section of the WG meeting for discussing ensemble initial conditions, stochastic physics & other aspects of improving our EPSs.  We also need to maintain an interest in ensemble verification & links with convective-scale EPS and the new sub-seasonal to seasonal group. TIGGE development Calibration, combination, products EPS improvement Time

Virtuous Circle Develop, Improve Evaluate, Diagnose Ensemble Forecasts To improve EPSs we need to develop a virtuous circle – best with a single group with focus on ensemble prediction

Towards a Global Interactive Forecast System (GIFS)  Our objective is to realise the benefits of THORPEX research by developing and evaluating probabilistic products.  Focus on risks of high-impact weather events – unlikely but potentially catastrophic.  First step: exchange of real-time tropical cyclone predictions using “Cyclone XML” format.  Followed by development of products based on gridded forecasts of heavy precipitation & strong wind. Piers Buchanan, Met Office

Tropical cyclone products from MRI/JMA Tetsuo Nakazawa

TC Strike probability at specific time (based on dressed ensemble) Wesley Smith, Paula McCaslin & Zoltan Toth, NOAA/ESRL

2. Website of RSMC La Réunion Website of RSMC La Réunion Matthieu Plu Nicole Girardot

Example: TC Bingzia (Feb 2011) 90 kt 85 kt80 kt Website of RSMC La Réunion Matthieu Plu Nicole Girardot

Aladin-Réunion forecast: mslp, rain and wind Website of RSMC La Réunion

Track Forecasts Official RSMC forecast Uncertainty cone (derived from EPS) Track forecasts from deterministic models Website of RSMC La Réunion

Strike Probabilities PEARP (Meteo-France) ECMWF EPS Website of RSMC La Réunion

Case 2: Flash floods/snow in South Africa (June 2011) East London, South Africa 00UTC 08 June, 2011 Case study & prototype products courtesy Mio Matsueda

Case 2: Flash floods/snow in South Africa (June 2011) + 9-day forecast

Case 2: Flash floods/snow in South Africa (June 2011) + 8-day forecast

Case 2: Flash floods/snow in South Africa (June 2011) + 7-day forecast

Case 2: Flash floods/snow in South Africa (June 2011) + 6-day forecast

Case 2: Flash floods/snow in South Africa (June 2011) + 5-day forecast

Case 2: Flash floods/snow in South Africa (June 2011) + 4-day forecast

Case 2: Flash floods/snow in South Africa (June 2011) + 3-day forecast

Case 2: Flash floods/snow in South Africa (June 2011) + 2-day forecast

Case 2: Flash floods/snow in South Africa (June 2011) + 1-day forecast

Other possible visualisation: combined warnings Prototype product courtesy Mio Matsueda

TIGGE and GIFS  What should be the balance between:  TIGGE and EPS research & development, or  Developing & evaluating new products for GIFS?  As discussed earlier, the GIFS-TIGGE WG will continue to develop & maintain TIGGE and take a broad interest in EPS research & development.  But we are not the right people to run a forecast demonstration project.  Instead, we will work closely with the CBS SWFDP and WWRP RDPs and FDPs on the evaluation of prototype products in specific regions.

Next steps to progress use of GIFS products in SWFDP  Provide documentation of prototype products  GIFS-TIGGE WG representative to attend SWFDP SG meeting early next year  Seek feedback from RSMCs coordinating SWFDP regional subprojects  Develop real-time products for SWFDP based on preferred prototypes  Provide training via SWFDP

Fostering new GIFS developments  Multi-model versions of existing products  Synthesise information from similar products currently produced by several centres  Develop novel products  To address requirements of users, in consultation with RMSCs  Improve communication between different groups working on product development – focus groups

GIFS-TIGGE 31 August - 2 September 2011  GEOWOW (GEOSS interoperability for Weather, Ocean and Water) is a 3-year EU-funded FP7 project starting September  The Weather component includes:  improving access to TIGGE data at ECMWF.  developing and demonstrating forecast products.  Weather participants: ECMWF, Met Office, Météo-France, KIT  Involve other TIGGE partners in planning development & demonstration of products in conjunction with SWFDP.

Summary  Since October 2006, the TIGGE archive has been accumulating regular ensemble forecasts from leading global NWP centres.  The TIGGE data set has been used for a wide range of scientific research studies.  Various products have been developed to use the tropical cyclone forecast data exchanged using CXML, and, more recently, prototype gridded products from the TIGGE data set.  The SWFDP regional centres will assess the prototype GIFS products for possible inclusion as real-time products on the SWFDP websites, and we will collaborate with them on implementation & evaluation. TIGGE website: