Climate change simulations of the South American Monsoon System CLARIS A Europe-South America Network for Climate Change Assessment and Impact Studies Rafael Terra IMFIA - Universidad de la República, Uruguay VAMOS/CLIVAR/WRCP 8th Annual Panel Meeting 7-9 de Marzo del 2005 México

Analysis Projects to IPCC AR4 k Dominant large-scale patterns influencing the seasonal predictability of precipitation over South America. PIs: Carolina Vera, CIMA/UBA; G. Silvestri, UBA; B. Liebmann (NOAA/CDC) k Frequency changes in daily weather regimes over South- Eastern South America. PIs: Jean-Philippe Boulanger, CNRS; G. Cazes and C. R. Mechoso, (Uruguay-UCLA). k Analysis of regional circulation regimes over southern South America and their response under global warming. PI: Silvina A. Solman, CIMA (UBA-CONICET). k Surface climate response associated with Southern Annular Mode (SAM) changes. PIs: Andrea Carril, INGV; C. Menéndez CIMA/UBA.

Dominant large-scale patterns influencing the seasonal predictability of precipitation over South America Carolina Vera (1), Gabriel Silvestri (1), and Brant Liebmann (2) (1)CIMA/CONICET-UBA, Buenos Aires, Argentina (2)NOAA/CDC, Boulder, Colorado, USA

1.To describe the relative contributions of the leading modes of variability of the atmospheric circulation and the SST in the SH to the precipitation variance over SESA in present climate (from reanalyses). 2.To investigate the ability of the climate models in reproducing the main features of such modes and their impact on South America precipitation. 3.To diagnose variations of the activity of the leading modes of atmospheric circulation and SST on climate change simulations and to assess climate change scenarios of precipitation over South America based on such variations. OBJECTIVES

Large-scale signatures on precipitation over SESA CORR(SSTA,PRECIP(SESA))CORR(STM200,PRECIP(SESA)) ND JF MA JF MA

Leading Patterns of 500-hPa height anomalies Pattern 1 Pattern 2 Pattern 3 (AAO) (PSA1) (PSA2) NCEP Re-analyses NASA (GISS- Model E20/ HYCOM) NASA (GISS- Model E20/ RUSSELL) Contour interval 3 m Contour interval 1 m 25% 7% 8% 18% 11% 8% 24% 7% 8% OND

ENSO NCEP Re-analyses NASA (GISS- Model E20/ HYCOM) NASA (GISS- Model E20/ RUSSELL) OND

Surface climate response associated with SAM changes First diagnostics using the multi-model dataset from PCMDI Andrea Carril (INGV, Bologna) Claudio Menéndez (CIMA, Buenos Aires)

Ensemble 2, 20C3m, 10 models, (34) runs, time slice cnrm_cm3 (1) 2.gfdl_cm2_0 (1) 3.giss_aom (2) 4.giss_model_e_h (5) 5.giss_model_e_r (9) 6.miroc3_2_hires (1) 7.miroc3_2_medres (3) 8.mri_cgcm2_3_2a (5) 9.ncar_ccsm3_0 (5: run 1, 3, 5, 6, 9) 10.ncar_pcm1(2) Ensemble 1, sresA2, 6 models, (12) runs, time slice cnrm_cm3 (1) 2.gfdl_cm2_0 (1) 3.giss_model_e_r (1) 4.miroc3_2_medres (3) 5.mri_cgcm2_3_2a (5) 6.ncar_pcm1(1) Based on the “Ensemble 2” for the present climate and on the “Ensemble 1” for the future climate (A2 scenario)

Anomalies removing the seasonal cycle and relative to every single run Linear detrend of the 30-year periods Ensemble is built by concatenating single runs METHODOLOGY

sresA2 z500 - EOF 1 (28%) 20C3m z500 - EOF 1 (28%)

Present climate: Composition for SAM+ events (1SD) Future climate: Composition for SAM+ events (1SD) Sea level Pressure Surface Temperature Precipitation Surface Temperature Precipitation

k Future scenarios of atmospheric circulation, precipitation and temperature in the South America Monsoon Region. PIs: Iracema F.A. Cavalcanti, P. L. Silva Dias, D. Herdies, C. Cunningham, H. Camargo, T.Tarasova, K.Andrade, (CPTEC-Brazil) k Sensitivity of South American Monsoon-related Features to Anthropogenic Changes in Radiative Forcing. PIs: A. Seth, S. Rauscher (IRI-USA), and M. Rojas (Chile) k Poleward penetration of the monsoon over the South American continent in a changing climate. PI: Rafael Terra, (IMFIA-Uruguay) k Tropical Extratropical interactions in present and future times: The connections between La Plata and the Amazon Basins. PIs: J. Marengo, C. Campos, M. de Mello and W. Soares (CPTEC-Brazil). Analysis Projects to IPCC AR4 (Continued)

OBJECTIVE: To identify in the future scenarios, changes in the atmospheric circulation patterns and climate variables over South America and nearby oceans, related to the life cycle of the SAMS. The purpose is to analyze changes in precipitation and temperature over South America, considering different regions, different regimes and changes that can occur in climatological systems, such as: Bolivia High, Upper level Cyclone Vortex over the Atlantic Ocean, ITCZ, SACZ, Atlantic and Pacific Subtropical Highs, Jet streams. Changes in tropical convection of other regions and connections with changes over South America will also be investigated using different statistical techniques, including clustering analysis, EOFs. Of particular interest is the analysis of changes in the general characteristics of the SH teleconnection patterns relevant to S. American climate. FUTURE SCENARIOS OF ATMOSPHERIC CIRCULATION, PRECIPITATION AND TEMPERATURE IN THE SOUTH AMERICA MONSOON REGION PIs: Iracema F.A. Cavalcanti, P. L. Silva Dias, D. Herdies, C. C Cunningham, H. Camargo, T. Tarasova, K. Andrade (Brazil).

PRECIPITATIONTEMPERATURE The two regions with larger changes in Precipitation are Southeast and Northeast Brazil and the La Plata basin region. Larger increase of Temperature over Central South America 1% CO2 EXPERIMENT Difference between (Years 71 to 280) - (Years 11 to 70)

Poleward penetration of the Monsoon over South America in a Changing Climate Rafael Terra, (IMFIA-Uruguay)

CO2 effect only:100 years Pre-Industrial 100 years 2 x CO2 100 years 4 x CO2 January only: “Deep” summer Multimodel:MPI Others Maps:2xCO2 – Pre-Industrial ANALYSES

Precipitation 2 mm/day contours (Red means less rain in 2xCO2) SST 1 °C Contours (Red means warmer in 2xCO2)

LONGWAVE SHORT WAVE HEAT FLUXES 10 W/m2 contours – (Red means higher fluxes into the ground in 2xCO2) ENERGY BUDGET AT THE SURFACE

WATER VAPOR PATH TOTAL CLOUDINESS 10% contours (Red means less clouds in 2xCO2) 5 Kg/m2 contours (Red means more WVP in 2xCO2) RADIATIVE FORCING

k Tropical South Atlantic/South America scenarios; assess ocean circulation changes associated with tropical-extratropical exchanges. PI: Ilana Wainer, USP. k The ENSO effects in the atmospheric circulation and in the climate of southern South America. PIs: V. Barros, I. Camilloni, M. Doyle (CIMA/UBA, Argentina). k Analysis of extreme indeces. PIs: M. Rusticucci and O. Peñalba, UBA; J. Marengo, CPTEC/INPE; M. Renom, UR; M. Núñez and C. Menéndez, CIMA/UBA. k The comparative analysis of interannual variability of global climate characteristics of the two hemispheres using adiabatic invariants. PI: I. Pisnitchenko (CPTEC, Brazil). Analysis Projects to IPCC AR4 (Continued)

Extreme indices in South America. Model vs. Station Data CLARIS Work Package 3.2: High-quality regional daily data base for climate trends and extreme event studies. MODEL: CCSR/NIES/FRCGC (hi-res), Japan. Rusticucci M., Penalba O. (Argentina); Marengo J. (Brazil); Renom M. (Uruguay). INDICES R95t: Percent of Annual Total Precipitation due to Events exceeding the th Percentile Tn90: Percent of time Tmin > 90th percentile value of daily minimum temperature. Station data: daily rainfall, maximum and minimum temperatures Period:

MODELDATA MEAN (% annual precip when precip > 95 percentile) SIGMA (interannual variability in %) R95T (Rainfall)

MODELDATA MEAN (% days when Tn>90 th ) SIGMA Interannual variability (%) Tn90 (MinTemp.)

Mean squared error (Model vs.Data) R95T (Rainfall)Tn90 (Temperature)

Regional climate scenarios based on GCMs: TRENDS OF THE SOUTH AMERICAN BORDER OF THE SOUTH ATLANTIC HIGH Vicente Barros, Ines Camilloni (CIMA/UBA) Objective The annual pattern of SLP in the western border of the South Atlantic High between 25°S and 45°S has shifted southward since 1950 as revealed by the NCEP reanalyses and synoptic data. This study discusses this shift using NCEP reanalyses and outputs from different GCMs. Future scenarios of the SLP patterns taken from GCMs are discussed. HADCM3, CSIRO Mk2, GFDL R30, ECHAM4/OPYC3 (done) GCMs for IPCC-AR4 (analysis in progress)

The first two patterns represent the winter and the summer fields and jointly explain 90 % of the variance. Results : PCA applied to the correlation matrix of seasonal means of SLP (NCEP, 1950/2000) The FLs of these two modes indicate a growing contribution to the total variance of the summer mode at the winter mode expense consistent with the observed southward trend of the regional field.

Results: PCA applied to the correlation matrix of seasonal means of SLP (GCMs, past+future) HADCM3 GFDL R30

Regional scenarios of climate change for southern South America Silvina Solman and Mario Nuñez CIMA (CONICET/UBA)

In the context of the Second National Communication (Argentina) regional scenarios of climate change have been derived nesting MM5 regional model into HadAM3 AGCM. Up to now, two 10-years simulations have been performed: Present Climate: Decade Future scenario: Decade A2 SRES