1. © Crown copyright Met Office WMO CBS operational collection/display of seasonal (and sub-seasonal) forecasts Richard Graham, Met Office Hadley Centre. With acknowledgements to all GPCs, LC- LRFMME, LC-SVSLRF and members of the WMO Expert Team on Extended and Long- range Forecasting (ET-ELRF) WMO/THORPEX/WCRP sub-seasonal to seasonal implementation planning meeting, WMO HQ, Geneva, 2-3 December 2011

2. © Crown copyright Met Office Content CBS operational seasonal (and monthly) data exchange and products – GPCs, Lead Centres Input on: Intra-seasonal applications Future CBS operational extended-range data exchange (in ET- ELRF terms of reference)

3. © Crown copyright Met Office WMO CBS coordination of centres producing long-range forecasts: Global Producing Centres (GPCs) 12 WMO-designated GPCs centres adhering to agreed procedures/standards in LRF – forming an integral part of the WMO GDPFS 2 Lead Centres, facilitating user access to GPC products Lead Centre for Long-range Forecast Multi-model Ensembles (LC- LRFMME) – jointly operated by KMA/NOAA NCEP Lead Centre for the Standard Verification System for Long-range Forecasts (LC-SVSLRF) – jointly operated by BoM/MSC Aim of this GDPFS infrastructure: improve access and usability of global LRF products to aid production of regional/national climate services Growing use at RCOFs and NCOFs

4. © Crown copyright Met Office GPC designation criteria have fixed production cycles and time of issuance; provide an agreed minimum set of long-range forecast products, 2m temp, precipitation, SST (averages of at least 1-month); any lead-time between 0 and 4 months. provide an agreed set of forecast quality measures (WMO Standard Verification System for LRF); provide up-to-date information on forecast methodology used; make products accessible to users (through website and Lead Centres)

5. GPC nameCentreSystem Configurati on (ensemble size of forecast) Resolution (atmosphere) Hindcast period used BeijingBeijing Climate CentreCoupled (48)T63/L161983-2004 CPTECCentre for Weather Forecasts and Climate Studies 2-tier (15)T62/L281979-2001 ECMWFEuropean Centre for Medium Range Weather Forecasts Coupled (41)T159/L621981-2005 ExeterMet Office Hadley Centre Coupled (42)1.25°x1.85°/L381989-2002 MelbourneAustralian Bureau of Meteorology Coupled (30)T47/L171980-2006 MontrealMeteorological Service of Canada 2-tier (40)T32/T63/T95/2.0 °x2.0° (4- model combination) 1969-2004 SeoulKorean Meteorological Agency 2-tier (20)T106/L211979-2007 TokyoJapan Meteorological Agency Coupled (51)T95/L401979-2008 ToulouseMétéo-FranceCoupled (41)T63/L911979-2007 WashingtonNational Centres for Environmental Prediction Coupled (40)T62/L641981-2004 MoscowHydromet Centre of Russia 2-tier (10)1.1°x1.4°/L281979-2003 PretoriaSouth African Weather Service 2-tier (6)T42/L191983-2001 The 12 WMO- designated GPCs

6. Data collected/processed/displayed by LC-LRFMME 1-month means for (at least) next 3-months; all ensemble members (forecast and hindcast); Variables: 2m temperature SST Total precipitation MSLP 850 hPa temperature 500 hPa geopotential height Collected every month between 15 th -20 th. Forecast displays updated on LC-LRFMME website ~ 20-25 th of month. © Crown copyright Met Office

7. Products Individual GPCs Deterministic (ensemble mean anomalies) Multi-model (deterministic+): ensemble mean anomalies Nino plumes Model consistency (of anomaly sign) multi-model can be user defined Multi-model (probabilistic) Probabilities of tercile categories Subset of GPCs © Crown copyright Met Office

8. Lead Centre for Long Range Forecast Multi Model Ensemble http://www.wmolc.org http://www.wmolc.org © Crown copyright Met Office

9. Seasonal AND monthly products displayed on LC-LRFMME website DecJanFeb DJF GPC Washington Ensemble mean anomalies: pmsl (2011)

10. GPC products from LC-LRFMME website: DJF 2010/11: ensemble mean pmsl anomaly Exeter ECMWF Toulouse Beijing Washington TokyoMelbourne Seoul Montreal Coupled systems Un-coupled systems Pretoria ‘Dynamic’ user- selectable domain Same available for individual months

11. Multi-model GPC products from LC-LRFMME website: DJF 2010/11, ensemble mean pmsl anomaly Ensemble mean of 10 GPCs Ensemble mean of 7 GPCs (coupled systems) Ensemble mean of 3 GPCs (un- coupled systems) multi-model subsets produced interactively from LC-LRFMME website Presented at South East Europe Regional Climate Outlook Forum (SEECOF), 22-26 November 2010 2mT, precipitation, T850, Z500, SST and for individual calendar month periods

12. Nino3.4 plumes

13. GPC model consistency plots: Individual months: number of models with +ve /-ve anomalies Z500T850PMSL Precip 2mTSST Dec 2011

14. GPC model consistency plots: Individual months: number of models with +ve /-ve anomalies Z500T850PMSL Precip 2mTSST DJF 2011

15. Probabilistic products with subset of GPC providing hindcasts Dec 2011

16. Probabilistic products with subset of GPC providing hindcasts DJF 2011

17. Use at RCOFs: WMO Lead Centre information and final GHACOF consensus, SOND 2010 LC-LRFMME Model consistency Statistical models + Forecaster judgement Final consensus Verification Observed SON anomalies 25 40 35 25 40

18. Summary – global LRF 12 WMO designated GPCs supply seasonal and ‘subseasonal‘ data 2 WMO Lead centres: dealing with standardised display/multi- modelling and forecast validation Deterministic products and probabilistic products In active use by RCCs, RCOFs, NMHSs (~123 registered users, 49 countries – as of early 2011) Probability products will form basis of prediction component of the WMO Global Seasonal Climate Update (GSCU). Key plans (guided by the Expert Team for Extended and Long- range Forecasts) – in line with GFCS vision - include: verification of multi-model products Investigation/development of extended (monthly) range capability investigation/development of multiannual–to-decadal capability (decadal GPCs?)

19. CSRP: consultation in Africa Type and number of organisations interviewed Ranking of priorities Questionnaire fielded to 9 climate service providers Total of 52 interviews across 8 African countries

20. Science component (3): Predicting onset timing based on local time of arrival of 20% of long-term seasonal average Average southward progression of rains with ITZC observed modelled Skill of Met Office seasonal forecasts of ‘onset’ timing early onset late onset orange/red = ‘good’ skill Encouraging first results: trial onset forecasts have been provided to Regional Climate Outlook Forums ICPAC, ACMAD and SADC-DMC Example: East Africa short-rains (OND) Michael Vellinga

21. Predicting onset timing: example Greater Horn of Africa short-rains season 2011 (OND) – prediction from August based on local time of arrival of 20% of long-term seasonal average Probability of early arrival Probability of late arrival Observed time of arrival

22. Early thoughts on LC-LRFMME operational exchange Strawman proposal for operational exchange: Coordinate research and operational exchanges with operational exchange a subset of research (delayed release) exchange? 2-weekly issues: first, with the release of LC-LRFMME seasonal forecast; second, 2 weeks later; Daily data to ~32 days; small number of essential variables; Products to be period means; 7 GPCs responded so far: 5 basically ‘yes’; 1 ‘too early’: 1 system not operational; Key issue: coordinating release date to get usefully short lead time, different GPCs have different release dates; should release date be fixed day of month or day of week? Some with data policy issues and other reservations (e.g. Timing of products) © Crown copyright Met Office

23. Thank you! Any questions?