GPC CPTEC Seasonal forecast activities update Caio Coelho

GPC CPTEC: Seasonal forecast activities update Caio Coelho caio. coelho@cptec. inpe. br CPTEC/INPE Presentation plan 1) Brazilian multi-model seasonal forecast 2) EUROBRISA multi-model system 3) Regionally downscaled forecast product 4) Final remarks Joint WGSIP/ET-OPSLS meeting Exeter, UK, 10 March 2014

Brazilian multi-model seasonal forecast system CPTEC/AGCM: Boundary conditions: persisted and predicted SST anomalies Convective parameterization schemes: Kuo, RAS, Grell 90 ensemble members CPT/IRI: Predictors (SST, Geopotential 500 h. Pa, vertical velocity 850 h. Pa) Time series models: Holt-Winters Arima ECHAM 4. 6/AGCM: Boundary conditions: persisted SST anomalies 20 ensemble members All models produced retrospective forecasts (hindcasts) for the period 1989 -2008 using exactly the same procedure used in real-time forecasting Joint effort: CPTEC/INPE, INMET and FUNCEME

CPTEC/INMET/FUNCEME Multi-model ensemble mean forecast JJA precipitation anomaly forecast skill: 1989 -2008 correlation Final probabilistic forecast derived from forecast anomaly and retrospective correlation skill Precipitation anomaly forecast for JJA 2013 (mm) Issued in May 2013

CPTEC/INMET/FUNCEME Multi-model probabilistic forecast Precipitation anomaly forecast skill: 1989 -2008 correlation Regression based probabilistic forecast obtained from forecast anomaly and past performance Issued: Forecast probabilities determined objectively May 2013

… task 5. 3. 1 EUROBRISA Integrated (empiricaldynamical combined and calibrated) precipitation seasonal forecasting system for South America Collaborative effort: INPE/CPTEC, Univ. Exeter, ECMWF, UK Met Office, Météo-France, UFPR, USP and INMET Previously supported by: Currently supported by: http: //eurobrisa. cptec. inpe. br Key idea: Why not combining all available state-of-the-art forecast information for improving 5 seasonal forecasts in South America - a region where the forecasts have skill and useful value

Updated EUROBRISA integrated forecasting system for South America Combined and calibrated coupled + empirical precip. Hybrid multi-model probabilistic system (NEW) Integrated forecast (NEW) Updated empirical model (NEW) Predictors: Atlantic and Pacific SST Predictand: Precipitation Coelho et al. (2006) J. Climate, 19, 3704 -3721 Hindcast period: 1981 -2010 Produced with forecast assimilation Stephenson et al (2005) Tellus A. Vol. 57, 253 -264 Implemented in Jul 2013 6 Both forecast and verification products available at http: //eurobrisa. cptec. inpe. br

Probabilistic forecast verification products for updated EUROBRISA system How well calibrated are EUROBRISA forecasts? How well do EUROBRISA forecasts detect below normal category events? 7

EUROBRISA integrated fcst for SON 2013 issued in August Empirical ECMWF UKMO Meteo-France Integrated Obs. SST anomaly Jul 2013 Prob. of most likely precipitation tercile (%) Issued: Aug 2013 8

BRAMS MAM 1989 seasonal precipitation forecasts for South America BRAMS: Brazilian Developments on the Regional Atmospheric Modelling System GPCP MAM 1989 CPTEC AGCM MAM 1989 BRAMS MAM 1989 Total precipitation (mm) Issued in previous Feb T 62 L 28 (~ 200 km x 200 km) 30 km x 30 km Persisted SST of previous Jan

CPTEC ETA model seasonal forecast for FMA 2013 issued in January 40 km x 40 km Persisted SST of previous Dec

Final remarks • CPTEC GPC forecast products, Brazilian Multi-model forecast system (CPTEC/INMET/FUNCEME), EUROBRISA and ETA forecast products routinely produced and used in national and regional climate outlook forums: demonstrated national and regional cooperation in providing access to forecast products • Currently testing new version of CPTEC AGCM with new physics and dynamics • Start investigating potential gain in predictive skill by increasing spatial forecast resolution when downscaling CPTEC AGCM forecasts with BRAMS