Eta Model seasonal forecasts and climatology ... - mtc-m17:80 - Inpe

Eta Model seasonal forecasts and climatology ... - mtc-m17:80 - Inpe

Eta Model seasonal forecastsand climatology over SouthAmericaSin Chan Chou, Josiane F. Bustamante, Jorge L.GomesCenter for Weather Prediction and Climate Studies - CPTECNational Institute for Space Research - INPECachoeira Paulista, SP, 12630-000, Brazil1

Model configurationDomain covers most part of South America• Resolution: 40 km, 38 layers, dt = 96s• Grid-point model (E-grid)• Eta vertical coordinate (Mesinger, 1984),• Model top: 25 hPa,• Integration length: 4.5 months,• Prognostic variables: T, q, u, v, p s, TKE, cloud water/ice,• Convection: Betts-Miller-Janjic scheme• Stratiform rain: Zhao scheme• Turbulence: Mellor Yamada 2.5;MO surface layer, Paulsonfunctions• Radiation: GFDL package, tendencies updated every hour,• Land surface scheme: OSU scheme, 2 soil layers,•.3

• Lower boundary conditions:• persisted SST anomaly, daily updated during integration• Climatological soil moisture• Seasonal albedo.

FMAM - 2002EtaObs

MJJA - 2002EtaObs

ASON - 2002EtaObs

NDJF - 2002EtaObs

Poor’s man model climatology5-year 4,5 month integrations:1996, 1997,1998,1999, 2000Model seasonal climatology - seasonal forecasts =anomaly forecastAssume: climatology and model systematic errors have been removed

SST:Observed monthly mean, 1o X 1o lat x lon,daily updatedInitial Soil Moisture: Monthly mean data, 2 soil layersAlbedo: Seasonal climatologyInitial Conditions: NCEP analyses at T62L28, on Day-15L. B. Conditions: CPTEC GCM simulations at T62L28, updt 6/6 h5-year seasonal climatology1997,1998,1999,2000, and2001.Period evaluated3 last months of the integrationDry (JJA) seasonRainy (DJF) season10

1997Eta ModelClim atologyDJFJJA199819992000IC:NCEP ModelT062L28LBC:CPTEC Global ModelT062L28 (6hours)Observed SSTupdated Daily2001Seasonal climatology were produced on a monthly basis, however,only the results of DJF season (a rainy season) and JJA season (a dryseason) are shown here.11

Obs5-yr climatologyDaily Mean PrecipitationDJFEta5-yr climatologyEta mean error12

Obs5-yr climatologyDaily Mean PrecipitationJJAEta5-yr climatologyEta mean error13

Mean Sea Level Pressure - DJFNCEP AnalysesEta ForecastLBC: CPTEC GCMFcst - AnlEta mean error14

Mean Sea Level Pressure - JJANCEP AnalysesEta ForecastLBC: CPTEC GCMEta mean error15

850-hPa Specific Humidity - DJFNCEP AnalysesEta ForecastLBC: CPTEC GCMEta mean error16

850-hPa Specific Humidity - JJANCEP AnalysesEta ForecastLBC: CPTEC GCMEta mean error17

Inter-annualvariabilityArea meanPrecipitation (mm)300250200150100500FCT x OBS - Monthly Prec. -N RegionprecipitationDec-97JanFebDec-98JanFebDec-99JanFebDec-00FCT x OBS - Monthly FC T Prec. O B S -CS RegionJanFebDec-01JanFebNNEPrecipitation (mm)160140120100806040200Dec-97JanFebDec-98JanFebDec-99JanFebDec-00FCT x OBS - Monthly FC T Prec. O B S -NE RegionJanFebDec-01JanFeb300CSPrecipitation (mm)250200150100500Dec-97JanFebDec-98JanFebDec-99FC TJanFebO B SDec-00JanFebDec-01JanFeb18

Inter-annual variabilityFCT x OBS - Monthly Precipitation -South America200150100500Dec-97JanFebDec-98JanFebDec-99Precipitation (mm)JanFebDec-00JanFebDec-01JanFebFC TO B S700DJF Total PrecipitationFCT x OBS - South America6005004003002001000D97-JF98 D98-JF99 D99-JF00 D00-JF01 D01-JF02FCTOBSThe interannual variability of the continental rains is reasonablycaptured by the model in the rainy season.19

Combination of ensemble generated by perturbation inthe initial conditions and model physicsMe m be rs De s c riptio n1 Con trol In itia l con d ition s : DAY – 1 52 In cr ea s e con vective r a in th rou gh clou d eficien cy3 Con tin en ta l con vective a ctivity equ a l to s ea con vective a ctivity4 Exten d con vective clou d life cycle5 Ea r lier in itia l con dition : DAY – 4 56 In itia l con d ition s : DAY – 1 77 In itia l con d ition s : DAY – 1 38 In itia l con d ition s : DAY – 1 320

Each physics perturbed member show comparable forecast skill one to the other.NDJF 2000-2001 - Area averagePrecipitation (mm)700650600550500450400350300250200SA AM NE CScontrolefi=1nolsmkta3600d-45meancmapNDJF 2001-2002 - Area averagePrecipitation (mm)650600550500450400350300250200SA AM NE CScontrolefi=1nolsmkta3600d-45meancmap21

Meses chuvosos de 5 anos:19981999200020012002Rodada Período de IntegraçãoOND Out-Nov-Dez-Jan-Fev-Mar-AbrNDJ Nov-Dez-Jan-Fev-Mar-AbrDJF Dez-Jan-Fev-Mar-AbrJFM Jan-Fev-Mar-AbrFMA Fev-Mar-AbrMe m bro s Cons truç ão do m e m bro1 Con trole Con d içã o In icia l: dia –1 52 Au m en to d a ch u va con vectiva p or eficiên cia tota l d a n u vem3 Ativida d e con vectiva con tin en ta l igu a l à oceâ n ica4 Au m en to d o ciclo de vid a d a n u vem con vectiva5 Con diçã o In icia l: d ia –456 Con diçã o In icia l: d ia –17 ou –1 3> Combinação de previsão por ensemblede condição inicial e de física

Eta•ENSEMBLE Mean NDJF 2002-2003 total precipitation - shaded•Spread of precipitation (4 months, mm) - lines•5 membersGCM23

2002-2003 NDJF precip total & SpreadInitial ConditionsPhysics•Some spread due to frontal passage•More spread in lower latitudes24

3-month total precipitation forecast over São Francisco Basin,BrazilEta1998 1999 2000 2001 2002GCMmm/dia14121086420OND 1997DJFFMAPrecipitação Bacia do São FranciscoAMJJJAASOONDDJFFMAAMJJJAASOONDDJFFMAAMJJJAASOONDDJFFMAAMJJJAASOONDDJFFMA1998 1999 2000 2001 2002AMJJJAASOONDDJFFMAm2m3m4m5obsm1

Preliminary ConclusionsA poor’s man 5-year model climatology of seasonal Eta Model forecastsover South America was produced and evaluated against NCEPanalyses.•The model in general captured the precipitation patterns in the rainy anddry seasons. Some larger errors occurred on three areas: south Chile,north Amazonia and eastern Brazil,•The interannual variability of the continental rains seems to bereasonably captured by the model.Next steps•Further investigation is necessary to identify the source of model errors.•Evaluate anomaly extracted from this climatology.•Include ensemble to the seasonal climatology,•Test increase of domain,•Test role of adjacent oceans.26•...

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