MJO prediction Intercomparison using the S2S Database Frédéric Vitart (ECMWF) Slide 1 WGNE Meeting 29 April 2016 1
INDEX The S2S project and S2S Database MJO prediction in S2S models MJO teleconnections in the Northern Extratropics Slide 2 WGNE Meeting 29 April 2016
The WWRP/WCRP Sub-seasonal to seasonal Prediction project (S2S) To improve forecast skill and understanding on the sub-seasonal to seasonal timescale with special emphasis on high-impact weather events To promote the initiative s uptake by operational centres and exploitation by the applications community To capitalize on the expertise of the weather and climate research communities to address issues of importance to the Global Framework for Climate Services Slide 3 WGNE Meeting 29 April 2016
Sub-seasonal to Seasonal (S2S) Prediction Project Teleconnections Sub-Projects Madden-Julian Oscillation Monsoons Africa Extremes Verification Research Issues Predictability Teleconnection O-A Coupling Scale interactions Physical processes Slide 4 WGNE Meeting 29 April 2016 Modelling Issues Initialisation Ensemble generation Resolution O-A Coupling Systematic errors Multi-model combination S2S Database Needs & Applications Liaison with SERA (Working Group on Societal and Economic Research Applications)
MJO Subproject MJO and Maritime Continent (MC) Interactions: Evaluating State of the Art & Characterizing Shortcomings In collaboration with the WGNE MJO Task Force Major Objectives: Assess current model simulation fidelity and prediction forecast skill over the MC across time scales, with emphasis on the MJO, and identify and rectify model biases. What roles do: 1) multi-scale interactions, 2) topography and land-sea contrast, and 3) ocean/land-atmosphere coupling play in the MC-MJO interaction and how do they influence predictability over the MC. Modeling Resources to Exploit 1) S2S Database, 2) MJOTF-GASS Multi-Model Exp and 3) ISVHE Future Field Campaign Year of Maritime Continent (YMC) is a multi-nation effort to carry out a field campaign in 2017-18 investigating multi-scale weather/climate processes over the MC. Workshop Spring 2016 MC Workshop, Singapore sponsored by S2S and MJOTF. Nexus of 1) land, atmosphere & ocean interactions and 2) multi-scale interactions: diurnal, mesoscale, Slide synoptic, 5 subseasonal, WGNE Meeting seasonal 29 April 2016 & interannual.
Slide 6 WGNE Meeting 29 April 2016 S2S Database
S2S Database l Daily near real-time forecasts (3 weeks behind time) + reforecasts l Common grid (1.5x1.5 degree) l Variables archived: about 80 variables including ocean variables, stratospheric levels and soil moisture and temperature S2S website: www.s2sprediction.net Slide 7 WGNE Meeting 29 April 2016
Contributing Centres to S2S database Data provider (11) Archiving centre (2) ECMWF NCEP ECCC UKMO Météo France ISAC HMCR CMA KMA JMA BoM Slide 8 WGNE Meeting 29 April 2016
S2S partners Resol. Ens. Size Freq. Hcsts Hcst length Hcst Freq Hcst Size ECMWF D 0-46 T639/319L91 51 2/week On the fly Past 20y 2/weekly 11 UKMO D 0-60 N216L85 4 daily On the fly 1996-2009 4/month 3 NCEP D 0-44 N126L64 4 4/daily Fix 1999-2010 4/daily 1 ECCC D 0-32 0.45x0.45 L40 21 weekly On the fly 1995-2014 weekly 4 CAWCR D 0-60 T47L17 33 2/week Fix 1981-2013 6/month 33 JMA D 0-34 T319L60 25 2/week Fix 1981-2010 3/month 5 KMA D 0-60 N216L85 4 daily On the fly 1996-2009 4/month 3 CMA D 0-45 T106L40 4 daily Fix 1886-2014 daily 4 CNRM D 0-32 T255L91 51 Weekly Fix 1993-2014 2/monthly 15 Timerange CNR- ISAC D 0-32 0.75x0.56 L54 40 weekly Fix 1981-2010 6/month 1 HMCR D 0-63 1.1x1.4 L28 20 weekly Fix 1981-2010 weekly 10 Slide 9 WGNE Meeting 29 April 2016
S2S data portal s2s.ecmwf.int or s2s.cma.cn Slide 10 WGNE Meeting 29 April 2016
S2S Database current status l Open access to researchers from ECMWF (since May 2015) and CMA (since Nov 2015). Subset of data also available from IRI. Data from ten data providers: ECMWF, NCEP, JMA, BoM, CMA, Météo-France, HMCR, ECCC, ISAC and UKMO l Plans End of 2016: all 11 Data Providers Add new ocean sub-surface and sea-ice variables Compute and archive indices such as MJO RMMS, SSW index, Weather regimes, Tropical storm tracks, Monsoon indices to be available for the research community from ECMWF and IRI servers. Slide 11 WGNE Meeting 29 April 2016
MJO Prediction in the S2S models Slide 12 WGNE Meeting 29 April 2016
Wheeler-Hendon MJO Index Combined EOF1 Combined EOF2 Slide 13 WGNE Meeting 29 April 2016 From Wheeler and Hendon, BMRC
MJO prediction Slide 14 WGNE Meeting 29 April 2016
Bivariate Correlation with ERA Interim Ensemble Mean 1999-2010 re-forecasts Slide 15 WGNE Meeting 29 April 2016 15
Bivariate Correlation with ERA Interim Ensemble Mean 1999-2010 re-forecasts Slide 16 WGNE Meeting 29 April 2016 16
Bivariate Correlation Ensemble vs control Slide 17 WGNE Meeting 29 April 2016 17
Amplitude error relative to ERA Interim Slide 18 WGNE Meeting 29 April 2016 18
Maritime Continent crossing Day 1-30 IC Slide 19 WGNE Meeting 29 April 2016 19
Spread/RMS error relationship - 2015 ECMWF BoM NCEP Slide 20 WGNE Meeting 29 April 2016 20
RMS Error Spread/RMS Error relationship PC1 and PC2 - RT WEEK1 WEEK2 WEEK3 WEEK4 ECMWF 51 members SPREAD BoM 33 members NCEP 16 members Slide 21 WGNE Meeting 29 April 2016 21
MJO Teleconnections: Z500 3rd pentad after Phase 3 NDJFM EI 0.48 NAO Index: mean=0, std=1.0 BoM 0.15 CMA 0.14 HMCR 0.13 NCEP 0.32 ISAC 0.25 CNRM 0.15 UKMO* 0.28 JMA 0.22 ECCC* 0.21 ECMWF 0.31 Slide 22 WGNE Meeting 29 April 2016
MJO Teleconnections: Z500 Slide 23 WGNE Meeting 29 April 2016
Impact of MJO amplitude on NAO teleconnections Slide 24 WGNE Meeting 29 April 2016
Impact of MJO Amplitude on the Amplitude of teleconnections S2S model ERA Interim Slide 25 WGNE Meeting 29 April 2016
Evolution of Teleconnection with lead time ECMWF MJO day 0-5 Z500 Lead time day 10-20 0.33 MJO day 5-10 Z500 Lead time day 15-25 0.31 MJO Phase 3 MJO day 10-15 Z500 Lead time day 20-30 0.30 MJO day 15-20 Z500 Lead time day 25-35 0.28 MJO day 20-25 Z500 Lead time day 30-40 0.26 MJO Phase 7-0.21-0.21-0.14-0.14-0.13 Slide 26 WGNE Meeting 29 April 2016
Amplitude MJO Teleconnections 3 rd pentad after an MJO in Phase 3 Slide 27 WGNE Meeting 29 April 2016
Conclusions S2S database: 10 models are currently available MJO skill scores: on average, correlation of 0.5 reached around day 20 In the models, there is a larger percentage of MJOs not crossing the MC than in re-analysis Not clear spread/skill relationship in ECMWF/BoM/NCEP models MJO Teleconnections: S2S models reproduce generally well the teleconnection patterns, but impact on Euro-Atlantic sector is too small. High resolution models tend to have stronger teleconnections. Models with stronger MJOs do not have stronger teleconnections. Slide 28 WGNE Meeting 29 April 2016
Bivariate Correlation with ERA Interim Ensemble Mean 1999-2010 re-forecasts All Year DJF Slide 29 WGNE Meeting 29 April 2016 29
Impact of the choice of the verification re-analysis Slide 30 WGNE Meeting 29 April 2016 30
Impact of horizontal resolution on teleconnection amplitude 3rd pentad after MJO in phase 3 3rd pentad after MJO in phase 7 Slide 31 WGNE Meeting 29 April 2016