Decadal prediction  Scientific interest  Meetings and Workshops  Organizational aspects  WGSIP role and activities

WGCM/WGSIP and Decadal Predictability

International scientific interest

CMIP5 Experiment Design “Long-Term” (century & longer) TIER 1 TIER 2 CORE “realistic” diagnostic “Near-Term” (decadal) (initialized ocean state) prediction & predictability CORE TIER 1

Active meeting and workshop schedule  OceanObs09 (Venice, Sept 09)  8 th Workshop on Decadal Climate Variability (Maryland, Oct 09)  Earth-System Initialization for Decadal Prediction (deBilt, Nov 09)  Predicting Climate of the Coming Decades (Miami, Jan 10)  WGSIP-13 (Buenos Aires, July 10)  Conference on Decadal Predictability (Triest, Aug, 10)  Workshop on Decadal Variability, Predictability and Predictions: understanding the role of the oceans (NCAR, Sept 10)  WGCM-14 (Exeter, Oct 10)  Seasonal to Multi-decadal Predictability of the Polar Climate (Bergen, Oct 10)  IPCC 1 st LA Meeting (Kunming, Nov 10)

OceanObs09 Decadal White Papers

Decadal prediction  Scientific interest  Meetings and Workshops  Organizational aspects focus survey panel IPCC  WGSIP role and activities

PCMDI website

Decadal prediction focus?  current CLIVAR site is really very good but perhaps “focus” on decadal aspect?  links from/to WGSIP, WGCM, WGOMD plus PCMDI to a CLIVAR “decadal prediction” page? currently under cross-cuts lacks a “name”  what’s in a name? “near-term” (decadal) hindcast/prediction simulations (!) WCRP decadal prediction CMIP5 near term experiments ….  what should be in the name? prediction or forecast (not simulation or experiment) timescale (near term climate, decadal, …) activity (project, intercomparison, …) sponsor/identifier (WCRP, CLIVAR, CMIP5, …)  something like CMIP5 Decadal Prediction Project (CDPP) or CMIP5 Decadal Forecasting Project (CDFP) ….  Does WGSIP want to make recommendations in this area (i.e. focus and name) ?

Organizational aspects of decadal prediction: survey  SIP community natural participants  Experience/ability in most needed aspects IPCC-class models initialization, ensemble generation retrospective forecast methodology forecast combination, calibration, skill measures … (external forcing)

WGSIP-12 Meeting Report

(include them?) ( CMIP )

should we survey both other questions or or keep it simple suitable wrt CHFP timeline

Results of draft CHFP survey

CHFP action items?  data considerations critical CIMA role for test data timeline  what of data not sent to CIMA EMSEMBLES CCCma, IRI, …  role for BADC? mirror CIMA actively collect data from other above sites

Results of draft CDFP survey Follow on activities … complete survey representative at WGCM meeting (Exeter, Oct.) …

WGSIP-12 Meeting Report

CMIP5-WGSIP-WGCM panel  At the Paris WGCM meeting a CMIP5-decadal Panel was struck consisting of Tim Stockdale and/or GJB (WGSIP), M. Latif, R. Stouffer (CMIP), G. Meehl (WGCM) I have included K. Taylor in any interactions such as they are  So far, the actions of the Panel have consisted in some discussion of the treatment of volcano forcing for decadal prediction resulted in a useful clarification no other burning questions have arisen so far  Presume WGSIP is keen to entrain the seasonal/interannual prediction (SIP) community into CMIP5-decadal very natural extension from SIP to seasonal/decadal (S2D) prediction has useful experience Item 17: “panel”

to CMIP5-WGSIP-WGCM panel  Suggesting potential actions which could be discussed at the upcoming WGSIP meeting in July: to circulate an to members of the community urging participation in CMIP5-decadal and pointing them to both the WGSIP and CMIP5 websites to feature an CMIP5-decadal link on the WGSIP (and perhaps other WGs’) front page(s) leading to some basic information and a link to the CMIP5 website to note the existence of the CMIP5-decadal (i.e. CDFP) Panel as a contact point for questions in this area (at the moment Karl appears as the contact for all of CMIP5 on various web sites)  WGSIP may also discuss how we might contribute to decadal studies in the areas of predictability, initialization, analysis and verification  Information you think the WG should be aware of or particular action they should consider taking?

WGCM (Meehl) suggests important activities in conjunction with WGSIP:  suggests WGSIP can provide guidance on how to evaluate the decadal hindcasts, experience in how to use hindcasts to evaluate predictions in the SI community ENSO hindcast activities as a possible template. important input for Ch 11 of the AR5  notes potential Aspen Workshop next summer: synthesis paper on decadal hindcasts- predictions for assessment by Ch 11, IPCC

CMIP5 (Taylor) responds  data questions and other technical questions mainly for CMIP5  will forward “science” questions he receives to Panel  (Latif: thanks for update … was panel officially established?) Possible follow up … Survey WGSIP subgroup on  “standard” analysis/verification  applications (?)  …. offer input to Aspen workshop perhaps …

WGSIP and the IPCC

WGSIP recommendations for Chapter 11? Title: Near-term climate prediction  long timescales in climate system forced and internally generated  predictability studies and results predictability as a feature of the physical system "skill" as our ability to correctly predict review of decadal scale predictability studies and implications  decadal forecast skill past studies but especially from CMIP5-decadal (CDFP) forecast combination, calibration, verification skill measures (deterministic and probabilistic)  predictions etc. (NOT projections dammit) from CMIP5-decadal deterministic and probabilistic in the context of past skill naturally includes regions - not a separate topic  summary

WGSIP recommendations for Chapter 11? The outline's last three topics:  Atmospheric composition and air quality  Possible effects of geoengineering  Quantification of the range of climate change projections  We will have few if any near term “forecasts" or "predictability studies" of: atmospheric composition and air quality effects of geoengineering  The "quantification" of decadal predictions (NOT long term projections) is already, and properly, part of the "forecast skill" don't need it as a separate topic don't want to make claims about Chapter 12 far-term climate projections  Does WGSIP have (should WGSIP have) recommendations for the organization of Chapter 11?

WGSIP decadal actions?  survey community as to status of CHFP and CDFP post results on website data, workshop implications for CHFP  CLIVAR site focus on “CDFP” links with and to WGSIP, WGCM, WGOMD sites (note CMIP5-decadal Panel as a contact point)  make comments/recommendations as to: methods, validation, evaluation, scores etc. IPCC Chapter 11 (topics, treatment..)

end of presentation

should we do this? other questions or or keep it simple?

Summary Decadal prediction a natural extension of WGSIP’s SIP interests and of the Climate-system Historical Forecast Project (CHFP) –IPCC class models –initialization of coupled system –retrospective forecasting of coupled system –focus on prediction and skill WGSIP/WGCM/CMIP5 partnership in “near term climate prediction” experiments – complementary expertise –expanded community of models –joint oversight group Where are we in WGSIP’s view –workshops/projects are addressing some basic aspects –CMIP provides infrastructure support –need for forcing data –WGSIP/WGCM collaboration –reasonable progress in prospect –anticipate further workshops (e.g dealing with results; combination, calibration, verification, implications for climate, application, value, …)

Other aspects; can WGSIP usefully address particular aspects of for instance:  retrospective forecast methodology  initialization, ensemble generation  forecast combination, calibration, skill measures  …. I.E. what is missing from meetings and workshops?

Predictability and prediction  predictability a characteristic of a physical system itself a measure of the rate of separation of initially close states indicates the possibility of prediction  prognostic predictability studies typically use model to simulate “rate of separation” presumption that the model “similar enough” to real system  forecast skill characterized by error growth rate, decorrelation, or other measure (rate of separation of actual and predicted states) indicates the current ability to predict  “potential predictability” analysis of variance; measure of signal to noise identifies regions where decadal variability is a useful fraction of the total variance meant to indicate that prediction is potentially possible

Key issues - deBilt