© Crown copyright Met Office WMO Lead-centres for verification and archiving Richard Graham (Met Office Hadley Centre) and Won-Tae Yun (KMA) acknowledgements.

© Crown copyright Met Office

WMO Lead-centres for verification and archivingRichard Graham (Met Office Hadley Centre) and Won-Tae Yun (KMA) acknowledgements to all GPCs and members of the WMO Expert Team on Extended and Long-range Forecasting (ET-ELRF)

WMO workshop on Sub-seasonal to Seasonal Prediction, Met Office, Exeter, 1-3 December 2010

Context

• Forecasters like to compare output from different models, this is helped by:

• easy access to products;

• same map projections, contour conventions etc;

• digital data for ‘user’ processing.

• Multi-model combinations also important

• Verification diagnostics also easier to use if presented uniformly

• Need for international coordination

ECMWF

JMA

2m temperature forecasts for DJF2010/11

© Crown copyright Met Office

WMO CBS coordination of centres producing long-range forecasts:Global Producing Centres (GPCs)

First step: agree standard forecast and verification output:

• Designate GPCs: centres adhering to agreed procedures/standards in LRF – there are now 12 GPCs, forming an integral part of the WMO GDPFS

Next step: increase coordination

• 2 Lead Centres, facilitating user access to GPC products

• Lead Centre for Long-range Forecast Multi-model Ensembles (LC-LRFMME)

• Lead Centre for the Standard Verification System for Long-range Forecasts (LC-SVSLRF)

• Aim: improve access and usability of global LRF products to aid production of regional/national climate services

© 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

© Crown copyright Met Office

WMO Lead Centre for LRF Multi-model Ensembles (LC-LRFMME)

http://www.wmolc.org/

Jointly operated byKorean Met Agency & NOAA NCEPWon-Tae Yun, Arun Kumar

• collect LRF data from GPCs

• core data: monthly pre-calculated anomalies (EM + members) active

• additional data: hindcast and forecast started but not active

• display GPC forecasts in standard formats (next 3-months only at present)

• generate and display an agreed set of MME products

• distribute GPC data (for those GPCs that allow it)

• promote research into MME techniques

Primary functions:

GPC forecasts for DJF 2010/11: ensemble mean pmsl anomaly (from LC-LRFMME web)

Exeter ECMWF Toulouse

Beijing

Washington

TokyoMelbourne

Seoul Montreal

Coupled systems

Un-coupled systems

Pretoria

‘Dynamic’ user-selectable domain

Multi-model GPC pmsl forecasts, DJF 2010/11from LC-LRFMME website

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

What about last year?pmsl anomalies: observed & GPC predictions from Nov09 for DJF2009/10

anomaly sign ‘consistency’Observed pmsl anomalies (wrt 61-90)

10-model multi-model EM

Other products/activities

Other variables:

• Nino3.4 region plumes

• 2m temperature; precipitation; 850 hPa temperature; 500hPa height; SST

Methods of multi-model combining:

• Operational: simple equal weights

• Research: skill weighted combination; linear and non-linear methods

Sub-seasonal:

• 1-month means available in addition to 3-month means

Note: ET-ELRF: last meeting recommended pilot projects on potential for monthly-range prediction for (e.g. rains onset)

© Crown copyright Met Office

Priority prediction needs Africa: rainfallDFID-Hadley Climate Science Research Partnership

• Poll of 9 African Regional Centres and National Meteorological Services • Highest priority: predictions of the temporal distribution of seasonal rainfall (e.g. onset,

duration, dry spells)• Less clear at what lead-time onset prediction is needed to be useful

0123456789

No

. o

f vo

tes Rank 1

Rank 2

Rank 3

Rank 4

Question: what next beyond standard 3-month means and terciles?

Lead Centre for Standard Verification of Long-range forecasts (LC-SVSLRF)

• repository of global SVSLRF scores for GPC forecasts

• Core of SVS: ROC maps and diagrams, reliability diagrams, MSSS

• documentation on verification scores (Attachment II-8 of the WMO manual on the GDPFS)

• observation datasets for verification, and code for calculating the SVSLRF scores

http://www.bom.gov.au/wmo/lrfvs/

Jointly operated byBureau of Met. BoM) & Met. Service of Canada (MSC)David Jones, Normand Gagnon

Examples of submitted data http://www.bom.gov.au/cgi-bin/climate/wmo.cgi

ROC curvesROC score maps

Reliability/sharpness diagrams

Courtesy: David Jones (BoM)

Use of Lead Centre products at African Regional Climate Outlook Forums (RCOFs)

GPC forecasts for E. Africa ‘short-rains’ SON 2010: ensemble mean rainfall anomaly

Exeter ECMWF Toulouse

Beijing

Washington

TokyoMelbourne

SeoulMoscow Montreal

Coupled systems

Un-coupled systems

Sample verification: ROC scores for SON precipitation, 1-month lead

ToulouseWashington TokyoMelbourne

above

below

0.6

WMO Lead Centre information and final consensus, SON 2010

Ensemble mean of 10 GPCs

Ensemble mean of 7 GPCs (coupled systems)

Ensemble mean of 3 GPCs (un-coupled systems)

Model consistency

Forecaster judgement

Final consensus

Verification

WMO Lead Centres in context of GFCS

GPCs: role in the Climate Services Information System (CSIS)

GPCs and their

LCs

Other Centres

Monitoring Centres

obs/research

users

GFCS

CSIS

WMO Global Seasonal Climate Updates (GSCUs)

• International consensus on global-scale seasonal monitoring and outlook (will extend the WMO El Niño/La Niña updates);

• Other climate indices (Indian Ocean Dipole, NAO)

• Temperature, precipitation

• Intended users: RCCs, RCOFs, NMHSs, but also ‘globally acting users’ (e.g. UN, Red Cross);

• Scoping meeting and first meeting of GSCU Task Team took place 12-15 October 2010;

• identified work needed before Pilot Phase can be begin

• requirements of GSCUs on the Lead Centres are feeding into work plans, e.g.:

• probability forecast products, extension of forecast range

• verification of the multi-model products

Summary

• WMO CBS (working with CCl) has designated GPCs and associated Lead Centres for multi-modelling and verification - strengthening coordination of LRF

• Forecast and verification products are available to RCCs /NMHSs / RCOFs - active use is being made

• Lead Centres will play a key role in WMO Global Seasonal Climate Updates (monitoring and outlook) – part of GFCS vision.

• Key plans for the WMO Lead Centres (guided by the Expert Team for Extended and Long-range Forecasts) include:

• development of probability forecast products

• extension prediction range (to ~6 months)

• verification of multi-model products

• possible centralisation of the verification process

• Issue of length of hindcast – but also of consistency of choice of the hindcast period across the GPCs

Thank you! Any questions?