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© Crown copyright Met Office
WMO CBS operational collection/display of seasonal (and sub-seasonal) forecastsRichard 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
© 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)
© 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
© 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)
GPC name Centre System Configuration (ensemble size of forecast)
Resolution (atmosphere)
Hindcast period used
Beijing Beijing Climate Centre Coupled (48) T63/L16 1983-2004
CPTEC Centre for Weather Forecasts and Climate Studies
2-tier (15) T62/L28 1979-2001
ECMWF European Centre for Medium Range Weather Forecasts
Coupled (41) T159/L62 1981-2005
Exeter Met Office Hadley Centre
Coupled (42) 1.25°x1.85°/L38 1989-2002
Melbourne Australian Bureau of Meteorology
Coupled (30) T47/L17 1980-2006
Montreal Meteorological Service of Canada
2-tier (40) T32/T63/T95/2.0°x2.0° (4- model combination)
1969-2004
Seoul Korean Meteorological Agency
2-tier (20) T106/L21 1979-2007
Tokyo Japan Meteorological Agency
Coupled (51) T95/L40 1979-2008
Toulouse Météo-France Coupled (41) T63/L91 1979-2007
Washington National Centres for Environmental Prediction
Coupled (40) T62/L64 1981-2004
Moscow Hydromet Centre of Russia
2-tier (10) 1.1°x1.4°/L28 1979-2003
Pretoria South African Weather Service
2-tier (6) T42/L19 1983-2001
The 12 WMO-designated GPCs
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 15th-20th. • Forecast displays updated on LC-LRFMME
website ~ 20-25th of month.© Crown copyright Met Office
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
Lead Centre for Long Range Forecast Multi Model Ensemblehttp://www.wmolc.org
© Crown copyright Met Office
Seasonal AND monthly products displayed on LC-LRFMME website
Dec Jan Feb
DJFGPC WashingtonEnsemble mean anomalies: pmsl(2011)
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
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
Nino3.4 plumes
GPC model consistency plots:Individual months:number of models with +ve /-ve anomalies
Z500 T850 PMSL
Precip 2mT SST
Dec 2011
GPC model consistency plots:Individual months:number of models with +ve /-ve anomalies
Z500 T850 PMSL
Precip 2mT SST
DJF 2011
Probabilistic products with subset of GPC providing hindcasts
Dec 2011
Probabilistic products with subset of GPC providing hindcasts
DJF 2011
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
35
25
40
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?)
CSRP: consultation in Africa
0123456789
No
. o
f vo
tes Rank 1
Rank 2
Rank 3
Rank 4
Type and number of organisations interviewed Ranking of priorities
Questionnaire fielded to 9 climate service providers
Total of 52 interviews across 8 African countries
Science component (3): Predicting onset timingbased 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
Predicting onset timing: example Greater Horn of Africa short-rains season 2011 (OND) – prediction from Augustbased on local time of arrival of 20% of long-term seasonal average
Probability of early arrival
Probability of late arrival
Observed time of arrival
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
Thank you! Any questions?